    Network Working Group                                      S. Waldbusser
    Request for Comments: 4011                                    Nextbeacon
    Category: Standards Track                                     J. Saperia
                                                        JDS Consulting, Inc.
                                                                   T. Hongal
                                                   Riverstone Networks, Inc.
                                                                  March 2005

                          Policy Based Management MIB

    Status of This Memo

       This document specifies an Internet standards track protocol for the
       Internet community, and requests discussion and suggestions for
       improvements.  Please refer to the current edition of the "Internet
       Official Protocol Standards" (STD 1) for the standardization state
       and status of this protocol.  Distribution of this memo is unlimited.

    Copyright Notice

       Copyright (C) The Internet Society (2005).

    Abstract

       This memo defines a portion of the Management Information Base (MIB)
       for use with network management protocols in TCP/IP-based internets.
       In particular, this MIB defines objects that enable policy-based
       monitoring and management of Simple Network Management Protocol
       (SNMP) infrastructures, a scripting language, and a script execution
       environment.

    Table of Contents

       1.  The Internet-Standard Management Framework ..................   3
       2.  Overview ....................................................   4
       3.  Policy-Based Management Architecture ........................   4
       4.  Policy-Based Management Execution Environment ...............  10
           4.1.  Terminology ...........................................  10
           4.2.  Execution Environment - Elements of Procedure .........  10
           4.3.  Element Discovery .....................................  11
                 4.3.1.  Implementation Notes ..........................  12
           4.4.  Element Filtering .....................................  13
                 4.4.1.  Implementation Notes ..........................  13
           4.5.  Policy Enforcement ....................................  13
                 4.5.1.  Implementation Notes ..........................  14
       5.  The PolicyScript Language ...................................  14
           5.1.  Formal Definition .....................................  15

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           5.2.  Variables .............................................  18
                 5.2.1.  The Var Class .................................  19
           5.3.  PolicyScript QuickStart Guide .........................  23
                 5.3.1.  Quickstart for C Programmers ..................  25
                 5.3.2.  Quickstart for Perl Programmers ...............  25
                 5.3.3.  Quickstart for TCL Programmers ................  25
                 5.3.4.  Quickstart for Python Programmers .............  26
                 5.3.5.  Quickstart for JavaScript/ECMAScript/JScript
                         Programmers ...................................  26
           5.4.  PolicyScript Script Return Values .....................  26
       6.  Index Information for `this element' ........................  27
       7.  Library Functions ...........................................  28
       8.  Base Function Library .......................................  29
           8.1.  SNMP Library Functions ................................  29
                 8.1.1.  SNMP Operations on Non-Local Systems ..........  30
                 8.1.2.  Form of SNMP Values ...........................  32
                 8.1.3.  Convenience SNMP Functions ....................  34
                         8.1.3.1.  getVar() ............................  34
                         8.1.3.2.  exists() ............................  34
                         8.1.3.3.  setVar() ............................  35
                         8.1.3.4.  searchColumn() ......................  36
                         8.1.3.5.  setRowStatus() ......................  38
                         8.1.3.6.  createRow() .........................  39
                         8.1.3.7.  counterRate() .......................  42
                 8.1.4.  General SNMP Functions ........................  44
                         8.1.4.1.  newPDU() ............................  45
                         8.1.4.2.  writeVar() ..........................  45
                         8.1.4.3.  readVar() ...........................  46
                         8.1.4.4.  snmpSend() ..........................  47
                         8.1.4.5.  readError() .........................  48
                         8.1.4.6.  writeBulkParameters() ...............  48
                 8.1.5.  Constants for SNMP Library Functions ..........  49
           8.2.  Policy Library Functions ..............................  51
                 8.2.1.  elementName() .................................  51
                 8.2.2.  elementAddress() ..............................  51
                 8.2.3.  elementContext() ..............................  52
                 8.2.4.  ec() ..........................................  52
                 8.2.5.  ev() ..........................................  52
                 8.2.6.  roleMatch() ...................................  52
                 8.2.7.  Scratchpad Functions ..........................  53
                 8.2.8.  setScratchpad() ...............................  55
                 8.2.9.  getScratchpad() ...............................  56
                 8.2.10. signalError() .................................  57
                 8.2.11. defer() .......................................  57
                 8.2.12. fail() ........................................  58
                 8.2.13. getParameters() ...............................  58
           8.3.  Utility Library Functions .............................  59
                 8.3.1.  regexp() ......................................  59

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                 8.3.2.  regexpReplace() ...............................  60
                 8.3.3.  oidlen() ......................................  60
                 8.3.4.  oidncmp() .....................................  60
                 8.3.5.  inSubtree() ...................................  60
                 8.3.6.  subid() .......................................  61
                 8.3.7.  subidWrite() ..................................  61
                 8.3.8.  oidSplice() ...................................  61
                 8.3.9.  parseIndex() ..................................  62
                 8.3.10. stringToDotted() ..............................  63
                 8.3.11. integer() .....................................  64
                 8.3.12. string() ......................................  64
                 8.3.13. type() ........................................  64
                 8.3.14. chr() .........................................  64
                 8.3.15. ord() .........................................  64
                 8.3.16. substr() ......................................  65
           8.4.  General Functions .....................................  65
       9.  International String Library ................................  65
           9.1.  stringprep() ..........................................  66
                 9.1.1.  Stringprep Profile ............................  66
           9.2.  utf8Strlen() ..........................................  67
           9.3.  utf8Chr() .............................................  68
           9.4.  utf8Ord() .............................................  68
           9.5.  utf8Substr() ..........................................  68
       10. Schedule Table ..............................................  69
       11. Definitions .................................................  70
       12. Relationship to Other MIB Modules ........................... 113
       13. Security Considerations ..................................... 114
       14. IANA Considerations ......................................... 117
       15. Acknowledgements ............................................ 118
       16. References .................................................. 118
           16.1. Normative References .................................. 118
           16.2. Informative References ................................ 119
       Authors' Addresses .............................................. 120
       Full Copyright Statement ........................................ 121

    1.  The Internet-Standard Management Framework

       For a detailed overview of the documents that describe the current
       Internet-Standard Management Framework, please refer to section 7 of
       RFC 3410 [16].

       Managed objects are accessed via a virtual information store, termed
       the Management Information Base or MIB.  MIB objects are generally
       accessed through the Simple Network Management Protocol (SNMP).
       Objects in the MIB are defined using the mechanisms defined in the
       Structure of Management Information (SMI).  This memo specifies a MIB
       module that is compliant to the SMIv2, which is described in STD 58,
       RFC 2578 [2], STD 58, RFC 2579 [3], and STD 58, RFC 2580 [4].

    Waldbusser, et al.          Standards Track                     [Page 3]

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    2.  Overview

       Large IT organizations have developed management strategies to cope
       with the extraordinarily large scale and complexity of today's
       networks.  In particular, they have tried to configure the network as
       a whole by describing and implementing high-level business policies,
       rather than manage device by device, where orders of magnitude more
       decisions (and mistakes) may be made.

       The following are examples of "business policies":

       - All routers will run code version 6.2.
       - On-site contractors will only be connected to ports that are
         configured with special security restrictions.
       - All voice over cable ports in California must provide free local
         calling.
       - Apply special forwarding to all ports whose customers have paid for
         premium service.

       Each of these policies could represent an action applied to hundreds
       of thousands of variables.

       To automate this practice, customers need software tools that will
       implement business policies across their networks, as well as
       standard protocols that will ensure that policies can be applied to
       all of their devices, regardless of the vendor.

       This practice is called Policy-Based Management.  This document
       defines managed objects for the Simple Network Management Protocol
       that are used to distribute policies in a common form throughout the
       network.

    3.  Policy-Based Management Architecture

       Policy-based management is the practice of applying management
       operations globally on all managed elements that share certain
       attributes.

       Policies are intended to express a notion of:

          if (an element has certain characteristics) then (apply an
          operation to that element)

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       Policies take the following normal form:

          if (policyCondition) then (policyAction)

       A policyCondition is a script that results in a boolean to determine
       whether an element is a member of a set of elements upon which an
       action is to be performed.

       A policyAction is an operation performed on an element or a set of
       elements.

       These policies are most often executed on or near managed devices
       where the elements live (and thus their characteristics may be easily
       inspected) and where operations on those elements will be performed.

       A management station is responsible for distributing an
       organization's policies to all the managed devices in the
       infrastructure.  The pmPolicyTable provides managed objects for
       representing a policy on a managed device.

       An element is an instance of a physical or logical entity and is
       embodied by a group of related MIB variables, such as all the
       variables for interface 7.  This enables policies to be expressed
       more efficiently and concisely.  Elements can also model circuits,
       CPUs, queues, processes, systems, etc.

       Conceptually, policies are executed in the following manner:

       for each element for which policyCondition returns true, execute
          policyAction on that element

       For example:

       If (interface is fast ethernet)       then (apply full-duplex mode)
       If (interface is access)              then (apply security filters)
       If (circuit w/gold service paid for)  then (apply special queuing)

       Each unique combination of policy and element is called an execution
       context.  Within a particular execution context, the phrase 'this
       element' is often used to refer to the associated element, as most
       policy operations will be applied to 'this element'.  The address of
       'this element' contains the object identifier of any attribute of the
       element, the SNMP context the element was discovered in, and the
       address of the system on which the element was discovered.

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       Policies can manage elements on the same system:

             -----------------------------------------------------
             |                                                   |
             |              Managed System                       |
             |                                                   |
             |                                                   |
             |   ------------------             Managed Elements |
             |   |                |               interfaces     |
             |   | Policy Manager | manages...    circuits       |
             |   |                |               queues         |
             |   ------------------               processes      |
             |                                    ...            |
             |                                                   |
             -----------------------------------------------------

       or they can manage elements on other systems:

                                                --------------------------
                                                |  Managed System        |
         --------------------------             |    Managed Elements    |
         |                        |             |      interfaces        |
         |  Management Station or |             |      circuits          |
         |    Mid-Level Manager   |             |      ...               |
         |                        |             --------------------------
         |   ------------------   | manages...
         |   | Policy Manager |   |             --------------------------
         |   ------------------   |             |  Managed System        |
         |                        |             |    Managed Elements    |
         --------------------------             |      interfaces        |
                                                |      circuits          |
                                                |      ...               |
                                                --------------------------

                                                ...

       PolicyConditions have the capability of performing comparison
       operations on SNMP variables, logical expressions, and other
       functions.  Many device characteristics are already defined in MIB
       Modules and are easy to include in policyCondition expressions
       (ifType == ethernet, frCircuitCommittedBurst < 128K, etc).  However,
       there are important characteristics that aren't currently in MIB
       objects, and, worse, it is not current practice to store this
       information on managed devices.  Therefore, this document defines MIB
       objects for this information.  To meet today's needs there are three
       missing areas:  roles, capabilities, and time.

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       Roles

       A role is an administratively specified characteristic of a managed
       element.  As a selector for policies, it determines the applicability
       of the policy to a particular managed element.

       Some examples of roles are political, financial, legal, geographical,
       or architectural characteristics, typically not directly derivable
       from information stored on the managed system.  For example, "paid
       for premium service" or "is plugged into a UPS" are examples of
       roles, whereas the "percent utilization of a link" would not be.

       Some types of information one would put into a role include the
       following:

       political - describes the role of a person or group of people, or of
                   a service that a group of people uses.  Examples:
                   executive, sales, outside-contractor, customer.
            If (attached user is executive) then (apply higher bandwidth)
            If (attached user is outside-contractor) then (restrict access)

       financial/legal - describes what financial consideration was
                         received.  Could also include contractual or legal
                         considerations.  Examples: paid, gold, free, trial,
                         demo, lifeline.
            If (gold service paid for) then (apply special queuing)

       geographical - describes the location of an element.  Examples:
                      California, Headquarters, insecure conduit.
            If (interface leaves the building) then (apply special security)

       architectural - describes the network architects "intent" for an
                       element.  Examples: backup, trunk.
            If (interface is backup) then (set ifAdminStatus = down)

          Roles in this model are human-defined strings that can be
          referenced by policy code.  The role table in this MIB may be used
          to assign role strings to elements and to view all role string
          assignments.  Implementation-specific mechanisms may also be used
          to assign role strings; however, these assignments must be visible
          in the role table.  Multiple roles may be assigned to each
          element.  Because policy code has access to data in MIB objects
          that represent the current state of the system and (in contrast)
          role strings are more static, it is recommended that role strings
          not duplicate information available in MIB objects.  Role strings
          generally should be used to describe information not accessible in
          MIB objects.

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          Policy scripts may inspect role assignments to make decisions
          based on whether an element has a particular role assigned to it.

          The pmRoleTable allows a management station to learn what roles
          exist on a managed system.  The management station may choose not
          to install policies that depend on a role that does not exist on
          any elements in the system.  The management station can then
          register for notifications of new roles.  Upon receipt of a
          pmNewRoleNotification, it may choose to install new policies that
          make use of that new role.

       Capabilities

          The capabilities table allows a management station to learn what
          capabilities exist on a managed system.  The management station
          may choose not to install policies that depend on a capability
          that does not exist on any elements in the system.  The management
          station can then register for notifications of new capabilities.
          Upon receipt of a pmNewCapabilityNotification, it may choose to
          install new policies that make use of that new capability.

       Time

          Managers may wish to define policies that are intended to apply
          for certain periods of time.  This might mean that a policy is
          installed and is dormant for a period of time, becomes ready, and
          then later goes dormant again.  Sometimes these time periods will
          be regular (Monday-Friday 9-5), and sometimes ad hoc.  This MIB
          provides a schedule table that can schedule when a policy is ready
          and when it is dormant.

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       A policy manager contains the following:

             -------------------------------------------------------
             | Policy Manager                                      |
             |                                                     |
             |   ----------------------------------------          |
             |   | Agent                                |          |
             |   |                                      |          |
             |   |  ---------------------------------   |          |
             |   |  | Policy Download and Control   |   |          |
             |   |  |   pmPolicyTable               |   |          |
             |   |  |   pmElementTypeRegTable       |   |          |
             |   |  |   pmSchedTable                |   |          |
             |   |  ---------------------------------   |          |
             |   |                                      |          |
             |   |  ---------------------------------   |          |
             |   |  | Policy Environment Control    |   |          |
             |   |  |   pmRoleTable                 |   |          |
             |   |  |   pmCapabilitiesTables        |   |          |
             |   |  ---------------------------------   |          |
             |   |                                      |          |
             |   |  ---------------------------------   |          |
             |   |  | Policy Monitoring             |   |          |
             |   |  |   pmTrackingTables            |   |          |
             |   |  |   pmDebuggingTable            |   |          |
             |   |  ---------------------------------   |          |
             |   ----------------------------------------          |
             |                                                     |
             |   --------------------------------                  |
             |   | Execution Environment        |                  |
             |   |                              |                  |
             |   |  -----------------------     |                  |
             |   |  | Policy Scheduler    |     |                  |
             |   |  -----------------------     |                  |
             |   |  -----------------------     |                  |
             |   |  | Language            |     |                  |
             |   |  -----------------------     |                  |
             |   |  -----------------------     |                  |
             |   |  | Function Library    |     |                  |
             |   |  -----------------------     |                  |
             |   --------------------------------                  |
             -------------------------------------------------------

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    4.  Policy-Based Management Execution Environment

    4.1.  Terminology

       Active Schedule - A schedule specifies certain times that it will be
          considered active.  A schedule is active during those times.

       Valid Policy - A valid policy is a policy that is fully configured
          and enabled to run.  A valid policy may run unless it is linked to
          a schedule entry that says the policy is not currently active.

       Ready Policy - A ready policy is a valid policy that either has no
          schedule or is linked to a schedule that is currently active.

       Precedence Group - Multiple policies can be assigned to a precedence
          group with the resulting behavior that for each element, of the
          ready policies that match the condition, only the one with the
          highest precedence value will be active.  For example, if there is
          a default bronze policy that applies to any interface and a
          special policy for gold interfaces, the higher precedence of the
          gold policy will ensure that it is run on gold ports and that the
          bronze policy isn't.

       Active Execution Context - An active execution context is a pairing
          of a ready policy with an element that matches the element type
          filter and the policy condition.  If there are multiple policies
          in the precedence group, it is also necessary that no higher
          precedence policy in the group match the policy condition.

       Run-Time Exception (RTE) - A run-time exception is a fatal error
          caused in language or function processing.  If, during the
          invocation of a script, a run-time exception occurs, execution of
          that script is immediately terminated.  If a policyCondition
          experiences a run-time exception while processing an element, the
          element is not matched by the condition and the associated action
          will not be run on that element.  A run-time exception can cause
          an entry to be added to the pmDebuggingTable and will be reflected
          in the pmTrackingPEInfo object.

    4.2.  Execution Environment - Elements of Procedure

       There are several steps performed in order to execute policies in
       this environment:

          - Element Discovery
          - Element Filtering
          - Policy Enforcement

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    4.3.  Element Discovery

       An element is an instance of a physical or logical entity.  Examples
       of elements include interfaces, circuits, queues, CPUs, and
       processes.  Sometimes various attributes of an entity will be
       described through tables in several standard and proprietary MIB
       Modules.  As long as the indexing is consistent between these tables,
       the entity can be modeled as one element.  For example, the ifTable
       and the dot3Stats table both contain attributes of interfaces and
       share the same index (ifIndex), therefore they can be modeled as one
       element type.

       The Element Type Registration table allows the manager to learn what
       element types are being managed by the system and to register new
       types, if necessary.  An element type is registered by providing the
       OID of an SNMP object (i.e., without the instance).  Each SNMP
       instance that exists under that object is a distinct element.  The
       index part of the discovered OID will be supplied to policy
       conditions and actions so that this code can inspect and configure
       the element.  The agent can determine the index portion of discovered
       OIDs based on the length of the pmElementTypeRegOIDPrefix for the
       portion of the MIB that is being retrieved.  For example, if the
       OIDPrefix is 'ifEntry', which has 9 subids, the index starts on the
       11th subid (skipping the subidentifier for the column; e.g.,
       ifSpeed).

       For each element that is discovered, the policy condition is called
       with the element's name as an argument to see whether the element is
       a member of the set the policy acts upon.

       Note that agents may automatically configure entries in this table
       for frequently used element types (interfaces, circuits, etc.).  In
       particular, it may configure elements for which discovery is
       optimized in one or both of the following ways:

       1. The agent may discover elements by scanning internal data
          structures as opposed to issuing local SNMP requests.  It is
          possible to recreate the exact semantics described in this table
          even if local SNMP requests are not issued.

       2. The agent may receive asynchronous notification of new elements
          (for example, "card inserted") and use that information to create
          elements instantly rather than through polling.  A similar feature
          might be available for the deletion of elements.

       Note that upon restart, the disposition of agent-installed entries is
       described by the pmPolicyStorageType object.

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       A special element type "0.0" represents the "system element".  "0.0"
       represents the single instance of the system itself and provides an
       execution context for policies to operate on "the system" and on MIB
       objects modeled as scalars.  For example, "0.0" gives an execution
       context for policy-based selection of the operating system code
       version (likely modeled as a scalar MIB object).  The element type
       "0.0" always exists.  As a consequence, no actual discovery will take
       place and the pmElementTypeRegMaxLatency object will have no effect
       for the "0.0" element type.  However, if the "0.0" element type is
       not registered in the table, policies will not be executed on the
       "0.0" element.

       If the agent is discovering elements by polling, it should check for
       new elements no less frequently than pmElementTypeRegMaxLatency would
       dictate.  When an element is first discovered, all policyConditions
       are run immediately, and policyConditions that match will have the
       associated policyAction run immediately.  Subsequently, the
       policyCondition will be run regularly for the element, with no more
       than pmPolicyConditionMaxLatency milliseconds elapsing between each
       invocation.  Note that if an implementation has the ability to be
       alerted immediately when a particular type of element is created, it
       is urged to discover that type of element in this fashion rather than
       through polling, resulting in immediate configuration of the
       discovered element.

    4.3.1.  Implementation Notes

       Note that although the external behavior of this registration process
       is defined in terms of the walking of MIB tables, implementation
       strategies may differ.  For example, commonly used element types
       (such as interface) may have purpose-built element discovery
       capability built-in and advertised to managers through an entry in
       the pmElementTypeRegTable.

       Before registering an element type, a manager is responsible for
       inspecting the table to see whether it is already registered (either
       by the agent or by another manager).  Note that entries that differ
       only in the last subid (which specifies which object is an entry) are
       effectively duplicates and should be treated as such by the manager.

       The system that implements the Policy-Based Management MIB may not
       have knowledge of the format of object identifiers in other MIB
       Modules.  Therefore it is inappropriate for it to check these OIDs
       for errors.  It is the responsibility of the management station to
       register well-formed object identifiers.  For example, if an extra
       sub-identifier is supplied when the ifTable is registered, no

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       elements will be discovered.  Similarly, if a sub-identifier is
       missing, every element will be discovered numerous times (once per
       column) and none of the element addresses will be well formed.

    4.4.  Element Filtering

       The first step in executing a policy is to see whether the policy is
       ready to run based on its schedule.  If the pmPolicySchedule object
       is equal to zero, there is no schedule defined, and the policy is
       always ready.  If the pmPolicySchedule object is non-zero, then the
       policy is ready only if the referenced schedule group contains at
       least one valid schedule entry that is active at the current time.

       If the policy is ready, the next step in executing a policy is to see
       which elements match the policy condition.  The policy condition is
       called once for each element and runs to completion.  The element's
       name is the only argument that is passed to the condition code for
       each invocation.  No state is remembered within the policy script
       from the previous invocation of 'this element' or from the previous
       invocation of the policy condition, except for state accessible
       through library functions.  Two notable examples of these are the
       scratchpad functions, which explicitly provide for storing state, and
       the SNMP functions, which can store state in local or remote MIB
       objects.  If any run-time exception occurs, the condition will
       terminate immediately for 'this element'.  If the condition returns
       non-zero, the corresponding policy action will be executed for 'this
       element'.

       If an element matches a condition and it had not matched that
       condition the last time it was checked (or if it is a newly
       discovered element), the associated policyAction will be executed
       immediately.  If the element had matched the condition at the last
       check, it will remain in the set of elements whose policyAction will
       be run within the policyActionMaxLatency.

    4.4.1.  Implementation Notes

       Whether policy conditions are multi-tasked is an implementation-
       dependent matter.  Each condition/element combination is conceptually
       its own process and can be scheduled sequentially, or two or more
       could be run simultaneously.

    4.5.  Policy Enforcement

       For each element that has returned non-zero from the policy
       condition, the corresponding policy action is called.  The element's
       name is the only argument that is passed to the policy action for
       each invocation.  Except for state accessible from library functions,

    Waldbusser, et al.          Standards Track                    [Page 13]

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       no state is remembered from the policy condition evaluation, or from
       the previous condition/action invocation of 'this element' or from
       the previous invocation of the policy condition or action on any
       other element.  If any run-time exception occurs, the action will
       terminate immediately for 'this element'.

    4.5.1.  Implementation Notes

       How policy actions are multi-tasked is an implementation-dependent
       matter.  Each condition/element combination is conceptually its own
       process and can be scheduled sequentially, or two or more could be
       run simultaneously.

    5.  The PolicyScript Language

       Policy conditions and policy actions are expressed with the
       PolicyScript language.  The PolicyScript language is designed to be a
       small interpreted language that is simple to understand and
       implement; it is designed to be appropriate for writing small scripts
       that make up policy conditions and actions.

       PolicyScript is intended to be familiar to programmers that know one
       of several common languages, including Perl and C.  Nominally,
       policyScript is a subset of the C language; however, it was desirable
       to have access to C++'s operator overloading (solely to aid in
       documenting the language).  Therefore, PolicyScript is defined
       formally as a subset of the C++ language in which many of the
       operators are overloaded as part of the "var" class.  Note, however,
       that a PolicyScript program cannot further overload operators, as the
       syntax to specify overloading is not part of the PolicyScript syntax.
       A subset was used to provide for easy development of low-cost
       interpreters of PolicyScript and to take away language constructs
       that are peculiar to the C/C++ languages.  For example, it is
       expected that both C and Perl programmers will understand the
       constructs allowed in PolicyScript.

       Some examples of the C/C++ features that are not available are
       function definitions, pointer variables, structures, enums, typedefs,
       floating point and pre-processor functions (except for comments).

       This language is formally defined as a subset of ISO C++ [10] but
       only allows constructs that may be expressed in the Extended Backus-
       Naur Form (EBNF) documented here.  This is because although EBNF
       doesn't fully specify syntactical rules (it allows constructs that
       are invalid) and doesn't specify semantic rules, it can successfully
       be used to define the subset of the language that is required for

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       conformance to this specification.  Unless explicitly described
       herein, the meaning of any construct expressed in the EBNF can be
       found by reference to the ISO C++ standard.

       The use of comments and newlines are allowed and encouraged in order
       to promote readability of PolicyScript code.  Comments begin with
       '/*' and end with '*/' or begin with '//' and go until the end of the
       line.

       One subset is not expressible in the EBNF syntax: all variables
       within an instance of a PolicyScript script are within the same
       scope.  In other words, variables defined in a block delimited with
       '{' and '}' are not in a separate scope from variables in the
       enclosing block.

       PolicyScript code must be expressed in the ASCII character set.

       In the EBNF used here, terminals are character set members (singly or
       in a sequence) that are enclosed between two single-quote characters
       or described as a phrase between '<' and '>' characters.
       Nonterminals are a sequence of letters and underscore characters.  A
       colon (:) following a nonterminal introduces its definition, a
       production.  In a production, a '|' character separates alternatives.
       The '(' and ')' symbols group the enclosed items.  The '[' and ']'
       symbols indicate that the enclosed items are optional.  A '?'  symbol
       following an item indicates that the item is optional.  A '*' symbol
       following an item indicates that the item is repeated zero, one, or
       more times.  A '+' symbol following an item indicates that the item
       is repeated one or more times.  The symbol '--' begins a comment that
       ends at the end of the line.

    5.1.  Formal Definition

       The PolicyScript language follows the syntax and semantics of ISO C++
       [10], but is limited to that which can be expressed in the EBNF
       below.

       The following keywords are reserved words and cannot be used in any
       policy script.  This prevents someone from using a common keyword in
       another language as an identifier in a script, thereby confusing the
       meaning of the script.  The reserved words are:

          auto, case, char, const, default, do, double, enum, extern, float,
          goto, inline, int, long, register, short, signed, sizeof, static,
          struct, switch, typedef, union, unsigned, void, and volatile.

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       Any syntax error, use of a reserved keyword, reference to an unknown
       identifier, improper number of function arguments, error in coercing
       an argument to the proper type, exceeding local limitations on string
       length, or exceeding local limitations on the total amount of storage
       used by local variables will cause an RTE.

       PolicyScript permits comments using the comment delimiters, '/*' to
       '*/', or the start of comment symbol '//'.

    -- Lexical Grammar

       letter:       '_' | 'a' | 'b' | 'c' | 'd' | 'e' | 'f'
                   | 'g' | 'h' | 'i' | 'j' | 'k' | 'l' | 'm'
                   | 'n' | 'o' | 'p' | 'q' | 'r' | 's' | 't'
                   | 'u' | 'v' | 'w' | 'x' | 'y' | 'z'
                   | 'A' | 'B' | 'C' | 'D' | 'E' | 'F'
                   | 'G' | 'H' | 'I' | 'J' | 'K' | 'L' | 'M'
                   | 'N' | 'O' | 'P' | 'Q' | 'R' | 'S' | 'T'
                   | 'U' | 'V' | 'W' | 'X' | 'Y' | 'Z'

       digit:        '0' | '1' | '2' | '3' | '4'
                   | '5' | '6' | '7' | '8' | '9'

       non_zero:   '1' | '2' | '3' | '4' | '5' | '6' | '7' | '8' | '9'

       oct_digit:  '0' | '1' | '2' | '3' | '4' | '5' | '6' | '7'

       hex_digit:    digit | 'a' | 'b' | 'c' | 'd' | 'e' | 'f'
                           | 'A' | 'B' | 'C' | 'D' | 'E' | 'F'

       escape_seq:    '\''   |   '\"'   |   '\?'   |   '\\'
                    | '\a'   |   '\b'   |   '\f'   |   '\n'
                    | '\r'   |  '\t'    |   '\v'
                    | '\' oct_digit+    | '\x' hex_digit+

       non_quote:  Any character in the ASCII character set
                   except single quote ('), double quote ("),
                   backslash ('\'), or newline.

       c_char:            non_quote | '"' | escape_seq

       string_literal:    '"' s_char* '"'

       s_char:            non_quote | ''' | escape_seq

       char_constant:     ''' c_char '''

       decimal_constant:  non_zero digit*

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       octal_constant:    '0' oct_digit*

       hex_constant:      ( '0x' | '0X' ) hex_digit+

       integer_constant:  decimal_constant | octal_constant | hex_constant

       identifier:        letter ( letter | digit )*

    -- Phrase Structure Grammar

       -- Expressions

       primary_expr:      identifier | integer_constant | char_constant
                        | string_literal  |  '(' expression ')'

       postfix_expr:      primary_expr
                        | identifier '(' argument_expression_list? ')'
                        | postfix_expr '++'
                        | postfix_expr '--'
                        | postfix_expr '[' expression ']'

       argument_expression_list:
                          assignment_expr
                        | argument_expression_list ',' assignment_expr

       unary_expr:        postfix_expr  |  unary_op unary_expr

       unary_op:          '+' | '-' | '~' | '!' | '++' | '--'

       binary_expr:  unary_expr | binary_expr binary_op unary_expr

       binary_op:       '||' | '&&' | '|'  | '^'  | '&'  | '!='
                      | '==' | '>=' | '<=' | '>'  | '<'  | '>>'
                      | '<<' |  '-' | '+'  | '%'  | '/'  |  '*'

       assignment_expr:      binary_expr
                           | unary_expr assignment_op assignment_expr

       assignment_op:     '=' | '*='  | '/=' | '%=' | '+=' | '-='
                      | '<<=' | '>>=' | '&=' | '^=' | '|='

       expression:    assignment_expr | expression ',' assignment_expr

       -- Declarations

       declaration:       'var' declarator_list ';'

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       declarator_list:   init_declarator
                        | declarator_list ',' init_declarator

       init_declarator:   identifier [ '=' assignment_expr ]

       -- Statements

       statement:   declaration
                  | compound_statement
                  | expression_statement
                  | selection_statement
                  | iteration_statement
                  | jump_statement

       compound_statement:    '{' statement* '}'

       expression_statement:  expression? ';'

       selection_statement:
               'if' '(' expression ')' statement
             | 'if' '(' expression ')' statement 'else' statement

       iteration_statement:
               'while' '(' expression ')' statement
             | 'for' '(' expression? ';' expression? ';' expression? ')'
                   statement

       jump_statement:    'continue' ';'
                        | 'break' ';'
                        | 'return' expression? ';'

       -- Root production

       PolicyScript:     statement*

    5.2.  Variables

       To promote shorter scripts and ease in writing them, PolicyScript
       provides a loosely typed data class, "var", that can store both
       integer and string values.  The native C++ types (char, int, etc.)
       are thus unnecessary and have not been carried into the subset that
       comprises this language.  The semantics of the "var" type are modeled
       after those of ECMAScript[17].

          For example:

             var number = 0, name = "IETF";

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       This language will be executed in an environment where the following
       typedef is declared.  (Note that this typedef will not be visible in
       the policyCondition or policyAction code.)

          typedef ... var;

       Although this declaration is expressed here as a typedef, the
       'typedef' keyword itself is not available to be used in PolicyScript
       code.

    5.2.1.  The Var Class

       A value is an entity that takes on one of two types: string or
       integer.

       The String type is the set of all finite ordered sequences of zero or
       more 8-bit unsigned integer values ("elements").  The string type can
       store textual data as well as binary data sequences.  Each element is
       considered to occupy a position within the sequence.  These positions
       are indexed with nonnegative integers.  The first element (if any) is
       at position 0, the next element (if any) at position 1, and so on.
       The length of a string is the number of elements (i.e., 8-bit values)
       within it.  The empty string has length zero and therefore contains
       no elements.

       The integer type is the set of all integer values in the range
       -9223372036854775808 (-2^63) to 18446744073709551615 (2^64-1).  If an
       integer operation would cause a (positive) overflow, then the result
       is returned modulo 2^64.  If an integer operation would cause a
       (negative) underflow, then the result is undefined.  Integer division
       rounds toward zero.

       Prior to initialization, a var object has type String and a length of
       zero.

       The policy script runtime system performs automatic type conversion
       as needed.  To clarify the semantics of certain constructs it is
       useful to define a set of conversion operators: ToInteger(),
       ToString(), ToBoolean(), and Type().  These operators are not a part
       of the language; they are defined here to aid the specification of
       the semantics of the language.  The conversion operators are
       polymorphic; that is, they can accept a value of any standard type.

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       ToInteger

       The operator ToInteger converts its argument to a value of type
       Integer according to the following table:

             Integer            The result equals the input argument
                                (no conversion).
             String             See grammar and note below.
             integer_constant   The result equals the input argument
                                (no conversion).
             string_literal     See grammar and note below.
             char_constant      See grammar and note below.

       ToInteger Applied to Strings

       ToInteger applied to the String Type string_literal and to
       char_constants applies the following grammar to the input.  If the
       grammar cannot interpret the string as an expansion of
       numeric_string, then an RTE is generated.  Note that a numeric_string
       that is empty or contains only white space is converted to 0.

     -- EBNF for numeric_string

       numeric_string : white_space* numeric? white_space*

       white_space :      <TAB> |  <SP> |  <NBSP> |  <FF> |  <VT>
                        | <CR>  |  <LF> |  <LS>   |  <PS> |  <USP>

       numeric :        signed_decimal |  hex_constant | octal_constant |
                        enum_decimal

       signed_decimal:  [ '-' | '+' ] decimal_constant

       enum_decimal:    [ letter | digit | '-' ]* '(' decimal_constant ')'

       -- decimal_constant, hex_constant, and octal_constant are defined
       -- in the PolicyScript EBNF described earlier.

       Note that when the enum_decimal form is converted, the sequence of
       characters before the parenthesis and the pair of parenthesis
       themselves are completely ignored, and the decimal_constant inside
       the parenthesis is converted.  Thus, "frame-relay(32)" translates to
       the integer 32.

       Although this will make the script more readable than using the
       constant "32", the burden is on the code writer to be accurate, as
       "ethernet-csmacd(32)" and "frame-relay(999)" will also be accepted.

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       ToString

       The operator ToString converts its argument to a value of type String
       according to the following table:

          Integer           Return the string containing the decimal
                            representation of the input argument in
                            the form of signed_decimal, except that
                            no leading '+' will be used.
          String            Return the input argument (no conversion)
          integer_constant  Return the string containing the decimal
                            representation of the input argument in the
                            form of signed_decimal except that no
                            leading '+' will be used.
          string_literal    Return the input argument (no conversion)
          char_constant     Return the string of length one containing
                            the value of the input argument.

       ToBoolean

       The operator ToBoolean converts its argument to a value of type
       Integer according to the following table:

          Integer            The result is 0 if the argument is 0.
                             Otherwise the result is 1.
          String             The results is 0 if the argument is the
                             empty string.  Otherwise the result is 1.
          integer_constant   The result is 0 if the argument is 0.
                             Otherwise the result is 1.
          string_literal     The result is 0 if the argument is the
                             empty string.  Otherwise the result is 1.
          char_constant      The result is 1.

       Operators

       The rules below specify the type conversion rules for the various
       operators.

          A++:   A = ToInteger(A); A++;
          A--:   A = ToInteger(A); A--;
          ++A:   A = ToInteger(A); ++A;
          --A:   A = ToInteger(A); --A;
          +A:    ToInteger(A);
          -A:     -1 * ToInteger(A);
          ~A:    ToInteger(A);
          !A:    !ToBoolean(A);
          A * B, A - B, A & B, A ^ B , A | B, A << B, A >> B:
                 ToInteger(A) <operator> ToInteger(B)

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          A / B, A % B:
                 if (ToInteger(B) == 0)
                   RTE, terminate;
                 else
                   ToInteger(A) <operator> ToInteger(B)
          A + B:
                 if (Type(A) == String || Type(B) == String)
                   ToString(A) concatenated with ToString(B)
                 else
                   A + B
          Compound Assignment (<operator>=):
                  Simply follow rules above.  Note that type of LHS (Left
                  Hand Side) may be changed as a result.

          A < B, A > B, A <= B, A >= B, A == B, A != B:
                 if (Type(A) == String && Type(B) == String)
                     lexically compare strings with strcmp() logic
                 else
                     ToInteger(A) <operator> ToInteger(B)
           A && B:
                  if (ToBoolean(A))
                      ToBoolean(B);
                  else
                      false;
           A || B:
                  if (ToBoolean(A))
                      true;

                  else
                      ToBoolean(B);

           if(A):
                  if (ToBoolean(A))
           while(A):
                  while(ToBoolean(A))
           for(...; A; ...):
                 for(...; ToBoolean(A); ...)

           A[B] as a RHS (Right Hand Side) value:
                 if (Type(A) != String
                      || ToInteger(B) >= strlen(A))
                    RTE, terminate;
                 A[ ToInteger(B) ]
                 The contents are returned as a string of length one

            A[B] = C as a LHS value:
                 if (Type(A) != String
                      || ToInteger(B) >= strlen(A))

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                    RTE, terminate;
                 if (strlen(ToString(C)) == 0)
                    RTE, terminate
                 A[ ToInteger(B) ] = First octet of ToString(C)

                 Note that this is only applicable in a simple assignment.

       For example, in the expression

          "getVar("ifSpeed.1") < 128000"

       getVar always returns a string and '128000' is implicitly an integer.
       The rules for '<' dictate that if either argument is an integer then
       a 'numeric less than' is performed on ToInteger(A) and ToInteger(B).

       If "getVar("ifSpeed.1")" returns "64000", the expression can be
       translated to:

            ToInteger("64000") < ToInteger(128000); or,
            64000 < 128000; or,
            True

    5.3.  PolicyScript QuickStart Guide

       PolicyScript is designed so that programmers fluent in other
       languages can quickly begin to write scripts.

       One way to become familiar with a language is to see it in action.
       The following nonsensical script exercises most of the PolicyScript
       constructs (though it skips some usage options and many arithmetic
       operators).

          var x, index = 7, str = "Hello World", oid = "ifSpeed.";

          x = 0;
          while(x < 10){
              if (str < "Goodbye") /* string comparison */
                  continue;
              else
                  break;
              x++;
          }
          if (oidlen(oid) == 10)
              oid += "." + index; // append index to oid
          for(x = 0; x < 7; x++){
                str += "a";

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                var y = 12;
                index = ((x * 7) + y) % 3;
                if (str[6] == 'W')
                    return index;
          }
          return;

       The following examples are more practical:

       For a condition:
          // Return 1 if this is an interface and it is tagged
          // with the role "gold"
          return (inSubtree(elementName(), "ifEntry")
              && roleMatch("gold"))

       A condition/action pair:
       First, register the Host Resources MIB hrSWRunEntry as a new element
       in the pmElementTypeRegTable.  This will cause the policy to run for
       every process on the system.  The token '$*' will be replaced by the
       script interpreter with a process index (see Section 7 for a
       definition of the '$*' token).

       The condition:
          // if it's a process and it's an application and it's
          // consumed more than 5 minutes of CPU time
          return (inSubtree(elementName(), "hrSWRunEntry")
                  && getVar("hrSWRunType.$*") == 4  // app, not OS or driver
                  && getVar("hrSWRunPerfCPU.$*") > 30000) // 300 seconds

       The action:
          // Kill it
          setVar("hrSWRunStatus.$*", 4, Integer); // invalid(4) kills it

       A more substantial action to start an RMON2 host table on interfaces
       that match the condition:

          var pdu, index;

          pdu = newPDU();
          writeVar(pdu, 0, "hlHostControlDataSource.*",
                   "ifIndex." + ev(0), Oid);
          writeVar(pdu, 1, "hlHostControlNlMaxDesiredEntries.*", 1000,
                   Integer);
          writeVar(pdu, 2, "hlHostControlAlMaxDesiredEntries.*", 1000,
                   Integer);
          writeVar(pdu, 3, "hlHostControlOwner.*", "policy", String);

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          writeVar(pdu, 4, "hlHostControlStatus.*", "active(1)", Integer);
          if (createRow(pdu, 5, 4, 20, 65535, index) == 0
              || index == -1)
              return;

       Because PolicyScript is a least common denominator, it contains
       nothing that would astonish programmers familiar with C, C++, Perl,
       Tcl, JavaScript, or Python.  Although a new programmer may attempt to
       use language constructs that aren't available in PolicyScript, s/he
       should be able to understand any existing PolicyScript and will
       likely know how to use anything that is valid in PolicyScript.  The
       lists below quickly enumerate the changes of note for programmers
       coming from some particular languages.  These lists won't describe
       the unavailable constructs, but it is easy to see from the definition
       above what is available.

    5.3.1.  Quickstart for C Programmers

       - Character constants (i.e., 'c') are treated as one-character
         strings, not as integers.  So operations such as ('M' - 'A') or (x
         + 'A') will not perform as expected.
       - Functions can change the value of arguments even though they are
         not pointers (or called like '&arg').
       - All variables are in the same scope.

    5.3.2.  Quickstart for Perl Programmers

       - Comments are '/* comment */' and '// till end of line', not '#'.
       - No need to put a '$' in front of variables.
       - Strings are compared with ==, <=, <, etc. (details in Sec. 6.2.1).
       - Strings are concatenated with '+' (details in Sec. 6.2.1).
       - No variable substitution in "" strings.  '' strings are 1 char
         only.
       - Variables must be declared before use (but no type is necessary).
       - All variables are in the same scope.

    5.3.3.  Quickstart for TCL Programmers

       - Comments are '/* comment */' and '// till end of line', not '#'.
       - No need to put a '$' in front of variables.
       - Function calls are func-name(arg1, arg2, ...).
       - Square braces [] don't interpret their contents.
       - Double quotes "" surround a string, but no substitutions are
         performed ("" is like { } in TCL ).
       - Statements are terminated by a semicolon (;).
       - Instead of "Set a b", use "b = a;".
       - Strings are concatenated with '+' (details in Sec. 6.2.1).
       - All variables are in the same scope.

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    5.3.4.  Quickstart for Python Programmers

       - Comments are '/* comment */' and '// till end of line', not '#'.
       - Single quotes can be used only for single-character strings ('a').
       - Indentation doesn't matter.  Braces { } define blocks.
       - Variables must be declared before use (but no type is necessary).
       - The expressions for if and while are always surrounded by
         parenthesis, as in "if (x < 5)".
       - 'for' syntax is "for(expression; expression; expression)" (see
         EBNF).
       - All variables are in the same scope.

    5.3.5.  Quickstart for JavaScript/ECMAScript/JScript Programmers

       - Variables must be declared before use.
       - Functions can change the value of arguments.
       - All variables are in the same scope.

    5.4.  PolicyScript Script Return Values

       A PolicyScript script execution is normally ended by the execution of
       a return statement, or by having the flow of execution reach the end
       of the final statement in the script.  A normal script execution
       always returns a Boolean value.  If no explicit value is specified in
       the return statement, or if the flow of control proceeds through the
       end of the script, the return value is implicitly zero.  If an
       expression is provided with the return statement, the expression is
       evaluated, and the result of the expression is implicitly converted
       with the ToBoolean operator before being returned to the script
       execution environment.

       The return value of a policyCondition script is used to determine
       whether the associated policyAction script is executed.  If the
       returned value is zero, the associated policyAction script is not
       executed.  If the returned value is one, the associated policyAction
       script will be executed.

       The return value of a policyAction script is ignored.

       An RTE or invocation of the fail() function will cause the return
       value of the script to be set to zero.  Note however, that execution
       of the defer() or fail() functions may set the defer attribute so
       that the lower precedence script may be executed.  This is
       independent of the return value of the policy script execution.

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    6.  Index Information for 'this element'

       PolicyScript code needs a convenient way to get the components of the
       index for 'this element' so that they can perform SNMP operations on
       it or on related elements.

       Two mechanisms are provided.

       1. For all OID input parameters to all SNMP Library Functions (but
          not OID utility functions), the token "$n" ('$' followed by an
          integer between 0 and 128) can be used in place of any decimal
          sub-identifier.  This token is expanded by the agent at execution
          time to contain the nth subid of the index for the current
          element.  For example, if the element is interface 7, and the
          objectIdentifier is "1.3.6.1.2.1.2.2.1.3.$0", it will be expanded
          to "1.3.6.1.2.1.2.2.1.3.7".  The special token "$*" is expanded to
          contain all of the subidentifiers of the index of the current
          element, separated by '.' characters.

          It is an RTE if a token is specified that is beyond the length of
          the index for the current element.

          Note that the "$n" convention is only active within strings.

       2. The ec() and ev() functions allow access to the components of the
          index for 'this element'.  ec() takes no argument and returns the
          number of index components that exist.  ev() takes an integer
          argument specifying which component of the index (numbered
          starting at 0) and returns an integer containing the value of the
          n'th subidentifier.  Refer to the Library functions section for
          the complete definition of ec() and ev().

             For example, if 'this element' is frCircuitDLCI.5.57
                                               (ifIndex = 5, DLCI = 57)
                   then ec()  returns 2
                        ev(0) returns 5
                        ev(1) returns 57

          This is helpful when one wishes to address a related element.
          Extending the previous example, to find the port speed of the
          port, the circuit (above) runs over:

             portSpeed = getVar("ifSpeed." + ev(0));

          A script may check the type of 'this element' by calling the
          elementName() function.  Although it is possible to write a script
          that will work with different types of elements, many scripts will

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          assume a particular element type and will work incorrectly if used
          on different element types.

    7.  Library Functions

       Library functions are built-in functions available primarily to
       provide access to information on the local system or to manipulate
       this information more efficiently.  A group of functions is organized
       into a library, the unit of conformance for function implementation.
       In order to claim conformance to a library, an implementation must
       implement all functions in a library to the specifications of the
       library.

       In order for a management station or a condition or action to
       understand whether a certain library of functions is implemented,
       each library will have a name that it registers in the role table as
       a characteristic of the system element ("0.0") in the default SNMP
       context.  Thus, conformance to a library can be tested with the
       roleMatch library function (in the base library) with the call
       roleMatch ("libraryName", "0.0").

       Note that in the descriptions of these functions below, the function
       prototype describes the type of argument expected.  Even though
       variables are not declared with a particular type, their contents
       must be appropriate for each function argument.  If the type is
       variable, the keyword 'var' will be used.  If only a string is
       appropriate, the keyword 'string' will be used.  If only an integer
       is appropriate, the keyword 'integer' will be used.  If the argument
       is declared as 'string' or 'integer' and a value of a different type
       is passed, the argument will be coerced with ToInteger() or
       ToString().  Any failure of this coercion will cause an RTE (in
       particular for ToInteger(), which will fail if its string-valued
       argument is not a well-formed integer).

       In the function prototype, if the '&' character precedes the
       identifier for an argument, that argument may be modified by the
       function (e.g., "integer &result, ...)").  Arguments without the '&'
       character cannot be modified by the function.  In a script,
       modifiable arguments don't have to be preceded by a '&'.  It is an
       RTE if a constant is passed to a modifiable function argument
       (regardless of whether the function actually writes to the argument).

       In the function prototype, the '[' and ']' characters surround
       arguments that are optional.  In PolicyScript code, the optional
       argument may only be included if all optional arguments to the left
       of it are included.  The function may place restrictions on when an
       optional argument must, or must not, be included.

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       In the function prototype, if a type is listed before the name of the
       function, the function returns a value of that type.  If no type is
       listed, the function returns no value.

    8.  Base Function Library

       A standard base library of functions is available to all systems that
       implement this specification.  This library is registered with the
       name "pmBaseFunctionLibrary".  Although the specification of this
       library is modularized into 4 separate sections, conformance to the
       library requires implementation of all functions in all sections.

       The sections are:

          - SNMP library functions
          - Policy library functions
          - Utility functions
          - Library Functions

    8.1.  SNMP Library Functions

       Two sets of SNMP Library functions are available with different
       situations in mind:

       - Convenience SNMP Functions

         In an effort to keep simple things simple, these functions are easy
         to use and code that is easy to understand.  These functions will
         suffice for the majority of situations, where a single variable is
         referenced and the desired error recovery is simply (and
         immediately) to give up (and move to the next policy-element
         combination).  In more complex cases, the General SNMP Functions
         can be used at the cost of several times the code complexity.

         The convenience SNMP functions are getVar, exists, setVar,
         setRowStatus, createRow, counterRate, and searchColumn.

       - General SNMP Functions

         The General SNMP functions allow nearly any legal SNMP Message to
         be generated, including those with multiple varbinds, getNext
         operations, notifications, and messages with explicit addressing or
         security specifications.

         The general SNMP functions are writeVar, readVar, snmpSend,
         readError, and writeBulkParameters.

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    8.1.1.  SNMP Operations on Non-Local Systems

       From time to time, a script may have to perform an operation on a
       different SNMP system than that on which 'this element' resides.
       Scripts may also have to specify the use of alternate security
       parameters.  In order to do this, the following optional arguments
       are provided for the SNMP library functions:

       snmp-function(...[, integer mPModel,
                           string tDomain, string tAddress,
                           integer secModel, string secName,
                           integer secLevel, string contextEngineID
       ])

       For example:

           getVar("sysDescr.0", "", SNMPv3, "transportDomainUdpIpv4",
                  "192.168.1.1:161", USM, "joe", NoAuthNoPriv);

       The use of these arguments is denoted in function definitions by the
       keyword 'NonLocalArgs'.  The definitions of these arguments are as
       follows:

          'mPModel' is the integer value of the SnmpMessageProcessingModel
          to use for this operation.

          'tDomain' is a string containing an ASCII dotted-decimal object
          identifier representing the transport domain to use for this
          operation.

          'tAddress' is a string containing the transport address formatted
          according to the 'tDomain' argument.  The ASCII formats for
          various values of 'tDomain' are defined by the DISPLAY-HINT for a
          TEXTUAL-CONVENTION that represents an address of that type.  The
          DISPLAY-HINTs used are:

             tDomain                    Source of DISPLAY-HINT [5] [11]
             -------                    ----------------------
             transportDomainUdpIpv4     TransportAddressIPv4
             transportDomainUdpIpv6     TransportAddressIPv6
             transportDomainUdpDns      TransportAddressDns
             snmpCLNSDomain             snmpOSIAddress
             snmpCONSDomain             snmpOSIAddress
             snmpDDPDomain              snmpNBPAddress
             snmpIPXDomain              snmpIPXAddress
             rfc1157Domain              snmpUDPAddress
             Other                      Use DISPLAY-HINT "1x:"

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          'secModel' is the integer value of the SnmpSecurityModel to use
          for this operation.

          'secName' is a string value representing the SnmpSecurityName to
          use for this operation.

          'secLevel' is the integer value of the SnmpSecurityLevel to use
          for this operation.

          An SNMP operation will be sent to the target system by using
          security parameters retrieved from a local configuration datastore
          based on 'secModel', 'secName', and 'secLevel'.  It is the
          responsibility of the agent to ensure that sensitive information
          in the local configuration datastore is used on behalf of the
          correct principals, as identified by the security credentials of
          the last entity to modify the pmPolicyAdminStatus for a policy.

          To illustrate how this must be configured, consider an example in
          which 'joe' installs a policy on 'PMAgent' that will periodically
          configure objects on 'TargetAgent' with the credentials of
          'Operator'.  The following conditions must be true for this policy
          to execute with the proper privileges:

          - 'Operator's security credentials for TargetAgent must be
            installed in PMAgent's local configuration datastore (e.g.,
            usmUserTable [6]) indexed by TargetAgent's engineID and
            'Operator'.
          - VACM [9] must be configured on PMAgent so that 'joe' has access
            to the above entry in the appropriate MIB for the local
            configuration datastore (e.g., usmUserTable).
          - 'joe' must be the last user to modify the pmPolicyAdminStatus
            object for the policy.

          See the Security Considerations section for more information.

          For convenience, constants for 'mPModel', 'secModel', and
          'secLevel' are defined in the "Constants" section below.

          'contextEngineID' is a string representing the contextEngineID of
          the SNMP entity targeted by this operation.  It is encoded as a
          pair of hex digits (upper- and lowercase are valid) for each octet
          of the contextEngineID.  If 'tDomain' and 'tAddress' are provided
          but 'contextEngineID' is not, then the operation will be directed
          to the SNMP entity reachable at 'tDomain' and 'tAddress'.

          In order for PolicyScript code to use any of these arguments, all
          optional arguments to the left must be included.  'mPModel',
          'tDomain', 'tAddress', 'secModel', 'secName', and 'secLevel' must

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          be used as a group; if one is specified, they must all be.
          'contextEngineID' may only be specified if all others are
          specified.

          Note that a function that uses NonLocalArgs must provide a
          parameter for the contextName that will be required when the
          NonLocalArgs are present.  Many functions will have the following
          logic:

          ContextName NonLocalArgs
          Supplied    Supplied

          No          No            Addressed to default context on
                                    local system.
          Yes         No            Addressed to named context on
                                    local system.
          Yes         Yes           Addressed to named context on
                                    potentially remote system.
          No          Yes           Not allowed.

    8.1.2.  Form of SNMP Values

       Many of the library functions have input or output parameters that
       may be one of the many SMI data types.  The actual type is not
       encoded in the value but is specified elsewhere, possibly by nature
       of the situation in which it is used.  The exact usage for input and
       output is as follows:

       Any Integer value
          (INTEGER, Integer32, Counter32, Counter64, Gauge32, Unsigned32,
          TimeTicks, Counter64):

          On input:
             An Integer or a String that can be successfully coerced to an
             Integer with the ToInteger() operator.  It is an RTE if a
             string is passed that cannot be converted by ToInteger() into
             an integer.

             A string of the form

               enum_decimal: [ letter | digit | '-' ]* '(' decimal_constant
             ')'

             will also be accepted.  In this case the sequence of characters
             before the parentheses and the parentheses themselves are
             completely ignored, and the decimal_constant inside the
             parentheses is converted.  Thus, "frame-relay(32)" translates
             to the integer 32.

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          On output:
             An Integer containing the returned value.

       Octet String
          On input:
             Either a String or an Integer.  If an Integer, it will be
             coerced to a String with the ToString() function.  This string
             will be used as an unencoded representation of the octet string
             value.

          On output:
             A String containing the unencoded value of the octet string.

       Object Identifier
          On input and on output:
             A String containing a decimal ASCII encoded object identifier
             of the following form:

                oid:       subid [ '.' subid ]* [ '.' ]
                subid:     '0' | decimal_constant

          It is an RTE if an Object Identifier argument is not in the form
          above.  Note that a trailing '.' is acceptable and will simply be
          ignored.  (Note, however, that a trailing dot could cause a
          strncmp() comparison of two otherwise-identical OIDs to fail;
          instead, use oidncmp().)

          Note that ASCII descriptors (e.g., "ifIndex") are never used in
          these encodings "over the wire".  They are never returned from
          library functions; nor are they ever accepted by them.  NMS user
          interfaces are encouraged to allow humans to view object
          identifiers with ASCII descriptors, but they must translate those
          descriptors to dotted-decimal format before sending them in MIB
          objects to policy agents.

       Null
          On input:
             The input is ignored.

          On output:
             A zero length string.

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    8.1.3.  Convenience SNMP Functions

    8.1.3.1.  getVar()

       The getVar() function is used to retrieve the value of an SNMP MIB
       object instance.

          string getVar(string oid [, string contextName, NonLocalArgs])

             'oid' is a string containing an ASCII dotted-decimal
             representation of an object identifier (e.g.,
             "1.3.6.1.2.1.1.1.0").

             The optional 'contextName' argument contains the SNMP context
             on which to operate.  If 'contextName' is not present, the
             contextName of 'this element' will be used.  If 'contextName'
             is the zero-length string, the default context is used.

             The optional 'NonLocalArgs' provide addressing and security
             information to perform an SNMP operation on a system different
             from that of 'this element'.

             It is an RTE if the queried object identifier value does not
             exist.

             This function returns a string containing the returned value,
             encoded according to the returned type.  Note that no actual
             SNMP PDU has to be generated and parsed when the policy MIB
             agent resides on the same system as the managed elements.

             It is recommended that NMS user interfaces display and allow
             input of MIB object names by their descriptor values, followed
             by the index in dotted-decimal form (e.g., "ifType.7").

    8.1.3.2.  exists()

       The exists() function is used to verify the existence of an SNMP MIB
       object instance.

          integer exists(string oid [, string contextName, NonLocalArgs])

             'oid' is a string containing an ASCII dotted-decimal
             representation of an object identifier (e.g.,
             "1.3.6.1.2.1.1.1.0").

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             The optional 'contextName' argument contains the SNMP context
             on which to operate.  If 'contextName' is not present, the
             contextName of 'this element' will be used.  If 'contextName'
             is the zero-length string, the default context is used.

             The optional 'NonLocalArgs' provide addressing and security
             information to perform an SNMP operation on a system different
             from that of 'this element'.

             This function returns the value 1 if the SNMP instance exists
             and 0 if it doesn't exist.  Note that no actual SNMP PDU has to
             be generated and parsed when the policy MIB agent resides on
             the same system as the managed elements.

             It is recommended that NMS user interfaces display and allow
             input of MIB object names by their descriptor values, followed
             by the index in dotted-decimal form (e.g., "ifType.7").

    8.1.3.3.  setVar()

       The setVar() function is used to set a MIB object instance to a
       certain value.  The setVar() function is only valid in policyActions.

          setVar(string oid, var value, integer type
                 [, string contextName, NonLocalArgs] )

             'oid' is a string containing an ASCII dotted-decimal
             representation of an object identifier (e.g.,
             "1.3.6.1.2.1.1.1.0").

             'value' is a string encoded in the format appropriate to the
             'type' parameter.  The agent will set the variable specified by
             'oid' to the value specified by 'value'.

             'type' will be the type of the 'value' parameter and will be
             set to one of the values for DataType Constants.

             The optional 'contextName' argument contains the SNMP context
             on which to operate.   If 'contextName' is not present, the
             contextName of 'this element' will be used.  If 'contextName'
             is the zero length string, the default context is used.

             The optional 'NonLocalArgs' provide addressing and security
             information to perform an SNMP operation on a system different
             from that of 'this element'.  Note that no actual SNMP PDU has
             to be generated and parsed when the policy MIB agent resides on
             the same system as the managed elements.

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             It is an RTE if the set encounters any error.

             It is recommended that NMS user interfaces display and allow
             input of MIB object names by their descriptor values, followed
             by the index in dotted-decimal form (e.g., "ifType.7").

    8.1.3.4.  searchColumn()

          integer searchColumn(string columnoid, string &oid,
                               string pattern, integer mode
                               [, string contextName, NonLocalArgs])

             searchColumn performs an SNMP walk on a portion of the MIB
             searching for objects with values equal to the 'pattern'
             parameter.

             'columnoid' constrains the search to those variables that share
             the same OID prefix (i.e., those that are beneath it in the OID
             tree).

             A getnext request will be sent requesting the object identifier
             'oid'.  If 'oid' is an empty string, the value of 'columnoid'
             will be sent.

             The value returned in each response packet will be transformed
             to a string representation of the value of the returned
             variable.  The string representation of the value will be
             formed by putting the value in the form dictated by the "Form
             of SNMP Values" rules, and then by performing the ToString()
             function on this value, forming 'SearchString'.

             The 'mode' value controls what type of match to perform on this
             'SearchString' value.  There are 6 possibilities for mode:

               Mode               Search Action
               ExactMatch         Case sensitive exact match of 'pattern'
                                  and 'SearchString'.
               ExactCaseMatch     Case insensitive exact match of 'pattern'
                                  and 'SearchString'.
               SubstringMatch     Case sensitive substring match, finding
                                  'pattern' in 'SearchString'.
               SubstringCaseMatch Case insensitive substring match, finding
                                  'pattern' in 'SearchString'.
               RegexpMatch        Case sensitive regular expression match,
                                  searching 'SearchString' for the regular
                                  expression given in 'pattern'.

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               RegexpCaseMatch    Case insensitive regular expression match,
                                  searching 'SearchString' for the regular
                                  expression given in 'pattern'.

             Constants for the values of 'mode' are defined in the
             'Constants' section below.

             searchColumn uses the POSIX extended regular expressions
             defined in POSIX 1003.2.

             The optional 'contextName' argument contains the SNMP context
             on which to operate.  If 'contextName' is not present, the
             contextName of 'this element' will be used.  If 'contextName'
             is the zero-length string, the default context is used.

             The optional 'NonLocalArgs' provide addressing and security
             information to perform SNMP operations on a system different
             from that of 'this element'.

             If a match is found, 'oid' is set to the OID of the matched
             value, and 1 is returned.  If the search traverses beyond
             columnoid or returns an error without finding a match, zero is
             returned, and 'oid' isn't modified.

             To find the first match, the caller should set 'oid' to the
             empty string.  To find additional matches, subsequent calls to
             searchColumn should have 'oid' set to the OID of the last
             match, an operation that searchColumn performs automatically.

             For example:
                 To find an ethernet interface
                 oid = "";
                 searchColumn("ifType", oid, "6", 0);

             This sends a getnext request for ifType and continues to walk
             the tree until a value matching 6 is found or a variable
             returns that is not in the 'ifType' subtree.

             To find the next ethernet interface, assuming that interface 3
             was discovered to be the first:

                 oid = "ifType.3";
                 searchColumn("ifType", oid, "6", 0);

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             In a loop to determine all the ethernet interfaces, this looks
             as follows:

                 oid = "";
                 while(searchColumn("ifType", oid, "6", 0)){
                   /* Do something with oid */
                 }

             Note that in the preceding examples, "ifType" is used as a
             notational convenience, and the actual code downloaded to the
             policy MIB agent must use the string "1.3.6.1.2.1.2.2.1.3" as
             there may be no MIB compiler (or MIB file) available on the
             policy MIB agent.

             Note that if the value of 'columnoid' is too short and thus
             references too much of the object identifier tree (e.g.,
             "1.3.6"), 'columnoid' could end up searching a huge number of
             variables (if the value was "1.3.6", it would search ALL
             variables on the agent).  It is the responsibility of the
             caller to make sure that 'columnoid' is set appropriately.

    8.1.3.5.  setRowStatus()

          integer setRowStatus(string oid, integer maxTries
                               [, integer freeOnException , integer seed
                                , string contextName, NonLocalArgs])

             setRowStatus is used to automate the process of finding an
             unused row in a read-create table that uses RowStatus whose
             index contains an arbitrary integer component for uniqueness.

             'oid' is a string containing an ASCII dotted-decimal
             representation of an object identifier, with one of the subids
             replaced with a '*' character (e.g.,
             "1.3.6.1.3.1.99.1.2.1.9.*").  'oid' must reference an
             'instance' of the RowStatus object, and the '*' must replace
             any integer index item that may be set to some random value.

             setRowStatus will come up with a number for the selected index
             item and will attempt to create the instance with the
             createAndWait state.  If the attempt fails, it will retry with
             a different random index value.  It will attempt this no more
             than 'maxTries' times.

             If the optional 'freeOnException' argument is present and equal
             to 1, the agent will free this row by setting RowStatus to
             'destroy' if, later in the same script invocation, this script

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             dies with a run-time exception or by a call to fail().  Note
             that this does not apply to exceptions experienced in
             subsequent invocations of the script.

             If the optional 'seed' argument is present, the initial index
             will be set to 'seed'.  Otherwise it will be random.  'seed'
             may not be present if the 'freeOnException' argument is not
             present.

             The optional 'contextName' argument contains the SNMP context
             on which to operate.  If 'contextName' is not present, the
             contextName of 'this element' will be used.  If 'contextName'
             is the zero-length string, the default context is used.

             The optional 'NonLocalArgs' provide addressing and security
             information to perform an SNMP operation on a system different
             from that of 'this element'.

             setRowStatus returns the successful integer value for the
             index.  If it is unsuccessful after 'maxTries', or if zero or
             more than one '*' is in OID, -1 will be returned.

             The createRow function (below) can also be used when adding
             rows to tables.  Although createRow has more functionality,
             setRowStatus may be preferable in certain situations (for
             example, to have the opportunity to inspect default values
             created by the agent).

    8.1.3.6.  createRow()

          integer createRow(integer reqPDU, integer reqNumVarbinds,
                            integer statusColumn, integer maxTries,
                            integer indexRange,
                            integer &respPDU, integer &respNumVarbinds,
                            integer &index
                            [, integer freeOnException, string contextName,
                            NonLocalArgs])

             createRow is used to automate the process of creating a row in
             a read-create table whose index contains an arbitrary integer
             component for uniqueness.  In particular, it encapsulates the
             algorithm behind either the createAndWait or createAndGo
             mechanism and the algorithm for finding an unused row in the
             table.  createRow is not useful for creating rows in tables
             whose indexes don't contain an arbitrary integer component.

             createRow will perform the operation by sending 'reqPDU' and
             returning the results in 'respPDU'.  Both 'reqPDU' and

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             'respPDU' must previously have been allocated with newPDU.
             'reqPDU' and 'respPDU' may both contain the same PDU handle, in
             which case the 'reqPDU' is sent and then replaced with the
             contents of the received PDU.

             'reqNumVarbinds' is an integer greater than zero that specifies
             which varbinds in the PDU will be used in this operation.  The
             first 'reqNumVarbinds' in the PDU are used.  Each such varbind
             must be of a special form in which the object name must have
             one of its subids replaced with a '*' character (e.g.,
             "1.3.6.1.3.1.99.1.2.1.9.*").  The subid selected to be replaced
             will be an integer index item that may be set to some random
             value.  The same subid should be selected in each varbind in
             the PDU.

             'respNumVarbinds' will be modified to contain the number of
             varbinds received in the last response PDU.

             'statusColumn' identifies which varbind in 'pdu' should be
             treated as the RowStatus column, where 0 identifies the 1st
             varbind.

             createRow will come up with a random integer index value and
             will substitute that value in place of the '*' subid in each
             varbind.  It will then set the value of the RowStatus column to
             select the 'createAndGo' mechanism and execute the set.  If the
             attempt fails due to the unavailability of the 'createAndGo'
             mechanism, it will retry with the 'createAndWait' mechanism
             selected.  If the attempt fails because the chosen index value
             is already in use, the operation will be retried with a
             different random index value.  It will continue to retry
             different index values until it succeeds, until it has made
             'maxTries' attempts, or until it encounters an error.  The
             value of 'maxTries' should be chosen to be high enough to
             minimize the chance that as the table fills up an attempt to
             create a new entry will 'collide' too often and fail.

             All random index values must be between 1 and 'indexRange',
             inclusive.  This is so that values are not attempted for an
             index that fall outside of that index's restricted range (e.g.,
             1..65535).

             If the optional 'freeOnException' argument is present and equal
             to 1, the agent will free this row by setting RowStatus to
             'destroy' if, later in the same script invocation, this script
             dies with a run-time exception or by a call to fail().  Note
             that this does not apply to exceptions experienced in
             subsequent invocations of the script.

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             The optional 'contextName' argument contains the SNMP context
             on which to operate.  If 'contextName' is not present, the
             contextName of 'this element' will be used.  If 'contextName'
             is the zero-length string, the default context is used.

             The optional 'NonLocalArgs' provide addressing and security
             information to perform an SNMP operation on a system different
             from that of 'this element'.

             Note that no actual SNMP PDU has to be generated and parsed
             when the policy MIB agent resides on the same system as the
             managed elements.  If no PDU is generated, the agent must
             correctly simulate the behavior of the SNMP Response PDU,
             particularly in case of an error.

             This function returns zero unless an error occurs, in which
             case it returns the proper SNMP Error Constant.  If an error
             occurred, respPDU will contain the last response PDU as
             received from the agent unless no response PDU was received, in
             which case respNumVarbinds will be 0.  In any event, readError
             may be called on the PDU to determine error information for the
             transaction.

             The 'index' parameter returns the chosen index.  If successful,
             'index' will be set to the successful integer index.  If no
             SNMP error occurs but the operation does not succeed due to the
             following reasons, 'index' will be set to -1:

                1) Unsuccessful after 'maxTries'.
                2) An object name had no '*' in it.
                3) An object name had more than one '*' in it.

             For example, createRow() might be used as follows:

             var index, pdu = newPDU(), nVars = 0;

             writeVar(pdu, nVars++, "hlHostControlDataSource.*",
                      "ifIndex." + ev(0), Oid);
             writeVar(pdu, nVars++, "hlHostControlNlMaxDesiredEntries.*",
                      1000, Integer);
             writeVar(pdu, nVars++, "hlHostControlAlMaxDesiredEntries.*",
                      1000, Integer);
             writeVar(pdu, nVars++, "hlHostControlOwner.*", "policy",
                      String);
             writeVar(pdu, nVars++, "hlHostControlStatus.*", "active(1)",
                      Integer);
             if (createRow(pdu, nVars, 4, 20, 65535,
                           pdu, nVars, index) != 0

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                 || index == -1)
                 return;
             // index now contains index of new row

    8.1.3.7.  counterRate()

       When a policy wishes to make a decision based on the rate of a
       counter, it faces a couple of problems:

       1. It may have to run every X minutes but have to make decisions on
          rates calculated over at least Y minutes, where Y > X.  This would
          require the complexity of managing a queue of old counter values.

       2. The policy script has no control over exactly when it will run.

       The counterRate() function is designed to surmount these problems
       easily.

          integer counterRate(string oid, integer minInterval
                              [, integer 64bit,
                              string discOid, integer discMethod,
                              string contextName, NonLocalArgs])

             'counterRate' retrieves the variable specified by oid once per
             invocation.  It keeps track of timestamped values retrieved on
             previous invocations by this execution context so that it can
             calculate a rate over a period longer than that since the last
             invocation.

             'oid' is the object identifier of the counter value that will
             be retrieved.  The most recent previously saved value of the
             same object identifier that is at least 'minInterval' seconds
             old will be subtracted from the newly retrieved value, yielding
             a delta.  If 'minInterval' is zero, this delta will be
             returned.  Otherwise, this delta will be divided by the number
             of seconds elapsed between the two retrievals, and the
             integer-valued result will be returned (rounding down when
             necessary).

             If there was no previously saved retrieval older than
             'minInterval' seconds, then -1 will be returned.  It is an RTE
             if the query returns noSuchName, noSuchInstance, or
             noSuchObject or an object that is not of type Counter32 or
             Counter64.

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             The delta calculation will allow for 32-bit counter semantics
             if it encounters rollover between the two retrievals, unless
             the optional argument '64bit' is present and equal to 1, in
             which case it will allow for 64-bit counter semantics.

             'discOid' and 'discMethod' may only be present together.
             'discOid' contains an object identifier of a discontinuity
             indicator value that will be retrieved simultaneously with each
             counter value:

                1. If 'discMethod' is equal to 1 and the discontinuity
                   indicator is less than the last one retrieved, then a
                   discontinuity is indicated.
                2. If 'discMethod' is equal to 2 and the discontinuity
                   indicated is different from the last one retrieved, then
                   a discontinuity is indicated.

             If this value indicates a discontinuity, this counter value
             (and its timestamp) will be stored, but all previously stored
             counter values will be invalidated and -1 will be returned.

             The implementation will have to store a number of timestamped
             counter values.  The implementation must keep all values that
             are newer than minInterval seconds, plus the newest value that
             is older than minInterval seconds.  Other than this one value
             that is older than minInterval seconds, the implementation
             should discard any older values.

             For example:
               Policy that executes every 60 seconds:
                   rate = counterRate("ifInOctets.$*", 300);
                   if (rate > 1000000)
                       ...

             Another example, with a discontinuity indicator:

               Policy that executes every 60 seconds:
                   rate = counterRate("ifInOctets.$*", 300, 0,
                                      "sysUpTime.0", 1);
                   if (rate > 1000000)
                       ...

             Another example, with zero minInterval:
               Policy that executes every 60 seconds:
                   delta = counterRate("ifInErrors.$*", 0);
                   if (delta > 100)
                       ...

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             The optional 'contextName' argument contains the SNMP context
             on which to operate.  If 'contextName' is not present, the
             contextName of 'this element' will be used.  If 'contextName'
             is the zero-length string, the default context is used.

    8.1.4.  General SNMP Functions

       It is desirable that a general SNMP interface have the ability to
       perform SNMP operations on multiple variables at once and that it
       allow multiple varbind lists to exist at once.  The newPdu, readVar,
       and writeVar functions exist to provide these facilities in a
       language without pointers, arrays, and memory allocators.

       newPDU is called to allocate a PDU and return an integer handle to
       it.  As PDUs are automatically freed when the script exits and can be
       reused during execution, there is no freePDU().

       readVar and writeVar access a variable length varbind list for a PDU.
       The PDU handle and the index of the variable within that PDU are
       specified in every readVar and writeVar operation.  Once a PDU has
       been fully specified by one or more calls to writeVar, it is passed
       to snmpSend (by referencing the PDU handle) and the number of
       varbinds to be included in the operation.  When a response is
       returned, the contents of the response are returned in another PDU
       and may be read by one or more calls to readVar.  Error information
       may be read from the PDU with the readError function.  Because
       GetBulk PDUs send additional information in the SNMP header, the
       writeBulkParameters function is provided to configure these
       parameters.

       Varbinds in this data store are created automatically whenever they
       are written by any writeVar or snmpSend operation.

       For example:
         var pdu = newPDU();
         var nVars = 0, oid, type, value;

         writeVar(pdu, nVars++, "sysDescr.0", "", Null);
         writeVar(pdu, nVars++, "sysOID.0", "", Null);
         writeVar(pdu, nVars++, "ifNumber.0", "", Null);
         if (snmpSend(pdu, nVars, Get, pdu, nVars))
             return;
         readVar(pdu, 0, oid, value, type);
         readVar(pdu, 1, oid, value, type);
         readVar(pdu, 2, oid, value, type);
         ...

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       or,
         var pdu = newPDU();
         var nVars = 0, oid1, oid2;

         writeVar(pdu, nVars++, "ifIndex", "", Null);
         writeVar(pdu, nVars++, "ifType", "", Null);
         while(!done){
           if (snmpSend(pdu, nVars, Getnext, pdu, nVars))
               continue;
           readVar(pdu, 0, oid1, value, type);
           readVar(pdu, 1, oid2, value, type);
           /* leave OIDs alone, now PDU #0 is set up for next step
              in table walk. */
           if (oidncmp(oid1, "ifIndex", oidlen("ifIndex")))
             done = 0;
           ...
         }

       Note that in the preceding examples, descriptors such as ifType and
       sysDescr are used in object identifiers solely as a notational
       convenience.  The actual code downloaded to the policy MIB agent must
       use a dotted decimal notation only, as there may be no MIB compiler
       (or MIB file) available on the policy MIB agent.

       To conform to this specification, implementations must allow each
       policy script invocation to allocate at least 5 PDUs with at least 64
       varbinds per list.  It is suggested that implementations limit the
       total number of PDUs per invocation to protect other script
       invocations from a malfunctioning script (e.g., a script that calls
       newPDU() in a loop).

    8.1.4.1.  newPDU()

          integer newPDU()

             newPDU will allocate a new PDU and return a handle to the PDU.
             If no PDU could be allocated, -1 will be returned.  The PDU's
             initial values of nonRepeaters and maxRepetitions will be zero.

    8.1.4.2.  writeVar()

          writeVar(integer pdu, integer varBindIndex,
                   string oid, var value, integer type)

             writeVar will store 'oid', 'value', and 'type' in the specified
             varbind.

             'pdu' is the handle to a PDU allocated by newPDU().

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             'varBindIndex' is a non-negative integer that identifies the
             varbind within the specified PDU modified by this call.  The
             first varbind is number 0.

             'oid' is a string containing an ASCII dotted-decimal
             representation of an object identifier (e.g.,
             "1.3.6.1.2.1.1.1.0").

             'value' is the value to be stored, of a type appropriate to the
             'type' parameter.

             'type' will be the type of the value parameter and will be set
             to one of the values for DataType Constants.

             It is an RTE if any of the parameters don't conform to the
             rules above.

    8.1.4.3.  readVar()

          readVar(integer pdu, integer varBindIndex, string &oid,
                  var &value, integer &type)

             readVar will retrieve the oid, the value, and its type from the
             specified varbind.

             'pdu' is the handle to a PDU allocated by newPDU().

             'varBindIndex' is a non-negative integer that identifies the
             varbind within the specified PDU read by this call.  The first
             varbind is number 0.

             The object identifier value of the referenced varbind will be
             copied into the 'oid' parameter, formatted in an ASCII dotted-
             decimal representation (e.g., "1.3.6.1.2.1.1.1.0").

             'value' is the value retrieved, of a type appropriate to the
             'type' parameter.

             'type' is the type of the value parameter and will be set to
             one of the values for DataType Constants.

             It is an RTE if 'pdu' doesn't reference a valid PDU or
             'varBindIndex' doesn't reference a valid varbind.

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    8.1.4.4.  snmpSend()

          integer snmpSend(integer reqPDU, integer reqNumVarbinds,
                           integer opcode,
                           integer &respPDU, integer &respNumVarbinds,
                           [, string contextName , NonLocalArgs] )

             snmpSend will perform an SNMP operation by sending 'reqPDU' and
             returning the results in 'respPDU'.  Both 'reqPDU' and
             'respPDU' must previously have been allocated with newPDU.
             'reqPDU' and 'respPDU' may both contain the same PDU handle, in
             which case the 'reqPDU' is sent and then replaced with the
             contents of the received PDU.  If the opcode specifies a Trap
             or V2trap, 'respPDU' will not be modified.

             'reqNumVarbinds' is an integer greater than zero that specifies
             which varbinds in the PDU will be used in this operation.  The
             first 'reqNumVarbinds' in the PDU are used.  'respNumVarbinds'
             will be modified to contain the number of varbinds received in
             the response PDU, which, in the case of GetBulk or an error,
             may be substantially different from reqNumVarbinds.

             'opcode' is the type of SNMP operation to perform and must be
             one of the values for SNMP Operation Constants listed in the
             'Constants' section below.

             The optional 'contextName' argument contains the SNMP context
             on which to operate.  If 'contextName' is not present, the
             contextName of 'this element' will be used.  If 'contextName'
             is the zero-length string, the default context is used.

             Note that no actual SNMP PDU has to be generated and parsed
             when the policy MIB agent resides on the same system as the
             managed elements.  If no PDU is generated, the agent must
             correctly simulate the behavior of the SNMP Response PDU,
             particularly in case of an error.

             This function returns zero unless an error occurs, in which
             case it returns the proper SNMP Error Constant.  If an error
             occurred, respPDU will contain the response PDU as received
             from the agent, unless no response PDU was received, in which
             case respNumVarbinds will be 0.  In any event, readError may be
             called on the PDU to determine error information for the
             transaction.

             If an SNMP Version 1 trap is requested (the opcode is Trap(4)),
             then SNMP Version 2 trap parameters are supplied and converted
             according to the rules of RFC 3584 [8], section 3.2.  The first

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             variable binding must be sysUpTime.0, and the second must be
             snmpTrapOID.0, as per RFC 3416 [7], section 4.2.6.  Subsequent
             variable bindings are copied to the SNMP Version 1 trap PDU in
             the usual fashion.

    8.1.4.5.  readError()

          readError(integer pdu, integer numVarbinds, integer &errorStatus,
                    integer &errorIndex, integer &hasException)

             Returns the error information in a PDU.

             'errorStatus' contains the error-status field from the response
             PDU or a local error constant if the error was generated
             locally.  If no error was experienced or no PDU was ever copied
             into this PDU, this value will be 0.

             'errorIndex' contains the error-index field from the response
             PDU.  If no PDU was ever copied into this PDU, this value will
             be 0.

             'hasException' will be 1 if any of the first 'numVarbinds'
             varbinds in the PDU contain an exception (Nosuchobject,
             Nosuchinstance, Endofmibview); otherwise it will be 0.

             It is an RTE if 'pdu' does not reference a valid PDU or if
             'numVarbinds' references varbinds that aren't valid.

    8.1.4.6.  writeBulkParameters()

          writeBulkParameters(integer pdu, integer nonRepeaters,
                              integer maxRepetitions)

             Modifies the parameters in a PDU in any subsequent GetBulk
             operation sent by the PDU.  'nonRepeaters' will be copied into
             the PDU's non-repeaters field, and 'maxRepetitions' into the
             max-repetitions field.

             This function may be called before or after writeVar is called
             to add varbinds to the PDU, but it must be called before the
             PDU is sent; otherwise, it will have no effect.  A new PDU is
             initialized with nonRepeaters set to zero and maxRepetitions
             set to zero.  If a Bulk PDU is sent before writeBulkParameters
             is called, these default values will be used.  If
             writeBulkParameters is called to modify a PDU, it is acceptable
             if this PDU is later sent as a type other than bulk.  The
             writeBulkParameters call will only affect subsequent sends of
             Bulk PDUs.  If a PDU is used to receive the contents of a

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             response, the values of nonRepeaters and maxRepetitions are
             never modified.

    8.1.5.  Constants for SNMP Library Functions

       The following constants are defined for use with all SNMP Library
       Functions.  Policy code will be executed in an environment where the
       following constants are declared.  (Note that the constant
       declarations below will not be visible in the policyCondition or
       policyAction code.)  These constants are reserved words and cannot be
       used for any variable or function name.

       Although these declarations are expressed here as C 'const's, the
       'const' construct itself is not available to be used in policy code.

       // Datatype Constants

       // From RFC 2578 [2]
       const integer Integer       = 2;
       const integer Integer32     = 2;
       const integer String        = 4;
       const integer Bits          = 4;
       const integer Null          = 5;
       const integer Oid           = 6;
       const integer IpAddress     = 64;
       const integer Counter32     = 65;
       const integer Gauge32       = 66;
       const integer Unsigned32    = 66;
       const integer TimeTicks     = 67;
       const integer Opaque        = 68;
       const integer Counter64     = 70;

       // SNMP Exceptions from RFC 3416 [7]
       const integer NoSuchObject         = 128;
       const integer NoSuchInstance       = 129;
       const integer EndOfMibView         = 130;

       // SNMP Error Constants from RFC 3416 [7]
       const integer NoError              = 0;
       const integer TooBig               = 1;
       const integer NoSuchName           = 2;
       const integer BadValue             = 3;
       const integer ReadOnly             = 4;
       const integer GenErr               = 5;
       const integer NoAccess             = 6;
       const integer WrongType            = 7;
       const integer WrongLength          = 8;
       const integer WrongEncoding        = 9;

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       const integer WrongValue           = 10;
       const integer NoCreation           = 11;
       const integer InconsistentValue    = 12;
       const integer ResourceUnavailable  = 13;
       const integer CommitFailed         = 14;
       const integer UndoFailed           = 15;
       const integer AuthorizationError   = 16;
       const integer NotWritable          = 17;
       const integer InconsistentName     = 18;

       // "Local" Errors
       // These are also possible choices for errorStatus returns
       // For example: unknown PDU, maxVarbinds is bigger than number
       // written with writeVar, unknown opcode, etc.
       const integer BadParameter         = 1000;

       // Request would have created a PDU larger than local limitations
       const integer TooLong              = 1001;

       // A response to the request was received but errors were encountered
       // when parsing it.
       const integer ParseError           = 1002;

       // Local system has complained of an authentication failure
       const integer AuthFailure          = 1003;

       // No valid response was received in a timely fashion
       const integer TimedOut             = 1004;

       // General local failure including lack of resources
       const integer GeneralFailure       = 1005;

       // SNMP Operation Constants from RFC 3416 [7]
       const integer Get                  = 0;
       const integer Getnext              = 1;
       const integer Set                  = 3;
       const integer Trap                 = 4;
       const integer Getbulk              = 5;
       const integer Inform               = 6;
       const integer V2trap               = 7;

       // Constants from RFC 3411 [1] for SnmpMessageProcessingModel
       const integer SNMPv1              = 0;
       const integer SNMPv2c             = 1;
       const integer SNMPv3              = 3;

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       // Constants from RFC 3411 [1] for SnmpSecurityModel
       const integer SNMPv1              = 1;
       const integer SNMPv2c             = 2;
       const integer USM                 = 3;

       // SnmpSecurityLevel Constants from RFC 3411 [1]
       const integer NoAuthNoPriv        = 1;
       const integer AuthNoPriv          = 2;
       const integer AuthPriv            = 3;

       // Constants for use with searchColumn
       const integer ExactMatch          = 0;
       const integer ExactCaseMatch      = 1;
       const integer SubstringMatch      = 2;
       const integer SubstringCaseMatch  = 3;
       const integer RegexpMatch         = 4;
       const integer RegexpCaseMatch     = 5;

    8.2.  Policy Library Functions

       Policy Library Functions provide access to information specifically
       related to the execution of policies.

    8.2.1.  elementName()

       The elementName() function is used to determine what the current
       element is and can be used to provide information about the type of
       element and how it is indexed.

          string elementName()

             elementName returns a string containing an ASCII dotted-decimal
             representation of an object identifier (e.g.,
             1.3.6.1.2.1.1.1.0).  This object identifier identifies an
             instance of a MIB object that is an attribute of 'this
             element'.

    8.2.2.  elementAddress()

          elementAddress(&tDomain, &tAddress)

             elementAddress finds a domain/address pair that can be used to
             access 'this element' and returns the values in 'tDomain' and
             'tAddress'.

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    8.2.3.  elementContext()

          string elementContext()

             elementContext() returns a string containing the SNMP
             contextName of 'this element'.

    8.2.4.  ec()

       The ec() (element count) and ev() (element value) functions provide
       convenient access to the components of the index for 'this element'.
       Typical uses will be in creating the index to other, related
       elements.

          integer ec()

             ec() returns an integer count of the number of index
             subidentifiers that exist in the index for 'this element'.

    8.2.5.  ev()

          integer ev(integer n)

             ev() returns the value of the nth subidentifier in the index
             for 'this element'.  The first subidentifier is indexed at 0.
             It is an RTE if n specifies a subidentifier beyond the last
             subidentifier.

    8.2.6.  roleMatch()

       The roleMatch() function is used to check whether an element has been
       assigned a particular role.

          integer roleMatch(string roleString [, string element,
                            string contextName, string contextEngineID])

             'roleString' is a string.  The optional argument 'element'
             contains the OID name of an element, defaulting to the current
             element if 'element' is not supplied.  If roleString exactly
             matches (content and length) any role assigned to the specified
             element, the function returns 1.  If no roles match, the
             function returns 0.

             The optional 'contextName' argument contains the SNMP context
             on which to operate.  If 'contextName' is not present, the
             contextName of 'this element' will be used.  If 'contextName'
             is the zero-length string, the default context is used.

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             'contextEngineID' contains the contextEngineID of the remote
             system on which 'element' resides.  It is encoded as a pair of
             hex digits (upper- and lowercase are valid) for each octet of
             the contextEngineID.  If 'contextEngineID' is not present, the
             contextEngineID of 'this element' will be used.
             'contextEngineID' may only be present if the 'element' and
             'context' arguments are present.

    8.2.7.  Scratchpad Functions

       Every maxLatency time period, every policy runs once for each
       element.  When the setScratchpad function executes, it stores a value
       named by a string that can be retrieved with getScratchpad() even
       after this policy execution code exits.  This allows sharing of data
       between a condition and an action, two conditions executing on
       different elements, or even different policies altogether.

       The value of 'scope' controls which policy/element combinations can
       retrieve this 'varName'/'value' pair.  The following are options for
       'scope':

          Global
             The 'varName'/'value' combination will be available in the
             condition or action of any policy while it is executing on any
             element.  Note that any information placed here will be visible
             to all other scripts on this system regardless of their
             authority.  Sensitive information should not be placed in
             global scratchpad variables.

          Policy
             The 'varName'/'value' combination will be available in any
             future execution of the condition or action of the current
             policy (regardless of what element the policy is executing on).
             If a policy is ever deleted, or if its condition or action code
             is modified, all values in its 'Policy' scope will be deleted.

          PolicyElement
             The 'varName'/'value' combination will be available in future
             executions of the condition or action of the current policy,
             but only when the policy is executing on the current element.
             If a policy is ever deleted, or if its condition or action code
             is modified, all values in its 'PolicyElement' scope will be
             deleted.  The agent may also periodically delete values in a
             'PolicyElement' scope if the corresponding element does not
             exist (in other words, if an element disappears for a period
             and reappears, values in its 'PolicyElement' scope may or may
             not be deleted).

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       setScratchpad's 'storageType' argument allows the script to control
       the lifetime of a variable stored in the scratchpad.  If the
       storageType is equal to the constant 'volatile', then this variable
       must be deleted on a reboot.  If it is equal to 'nonVolatile', then
       this variable should be stored in non-volatile storage, where it will
       be available after a reboot.  If the 'storageType' argument is not
       present, the variable will be volatile and will be erased on reboot.

       If the optional 'freeOnException' argument is present and equal to 1,
       the agent will free this variable if, later in the same script
       invocation, this script dies with a run-time exception or by a call
       to fail().  (Note that this does not apply to exceptions experienced
       in subsequent invocations of the script.)

       Note that there may be implementation-specific limits on the number
       of scratchpad variables that can be allocated.  The limit of unique
       scratchpad variables may be different for each scope or storageType.
       It is suggested that implementations limit the total number of
       scratchpad variables per script to protect other scripts from a
       malfunctioning script.  In addition, compliant implementations must
       support at least 50 Global variables, 5 Policy variables per policy,
       and 5 PolicyElement variables per policy-element pair.

       Scratchpad Usage Examples

       Policy  Element    Action
       A       ifIndex.1  setScratchpad(Global, "foo", "55")
       A       ifIndex.1  getScratchpad(Global, "foo", val) --> 55
       A       ifIndex.2  getScratchpad(Global, "foo", val) --> 55
       B       ifIndex.2  getScratchpad(Global, "foo", val) --> 55
       B       ifIndex.2  setScratchpad(Global, "foo", "16")
       A       ifIndex.1  getScratchpad(Global, "foo", val) --> 16

       Policy  Element    Action
       A       ifIndex.1  setScratchpad(Policy, "bar", "75")
       A       ifIndex.1  getScratchpad(Policy, "bar", val) --> 75
       A       ifIndex.2  getScratchpad(Policy, "bar", val) --> 75
       B       ifIndex.1  getScratchpad(Policy, "bar", val) not found
       B       ifIndex.1  setScratchpad(Policy, "bar", "20")
       A       ifIndex.2  getScratchpad(Policy, "bar", val) --> 75
       B       ifIndex.2  getScratchpad(Policy, "bar", val) --> 20

       Policy  Element    Action
       A       ifIndex.1  setScratchpad(PolicyElement, "baz", "43")
       A       ifIndex.1  getScratchpad(PolicyElement, "baz", val) --> 43
       A       ifIndex.2  getScratchpad(PolicyElement, "baz", val) not found
       B       ifIndex.1  getScratchpad(PolicyElement, "baz", val) not found
       A       ifIndex.2  setScratchpad(PolicyElement, "baz", "54")

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       B       ifIndex.1  setScratchpad(PolicyElement, "baz", "65")
       A       ifIndex.1  getScratchpad(PolicyElement, "baz", val) --> 43
       A       ifIndex.2  getScratchpad(PolicyElement, "baz", val) --> 54
       B       ifIndex.1  getScratchpad(PolicyElement, "baz", val) --> 65

       Policy  Element    Action
       A       ifIndex.1  setScratchpad(PolicyElement, "foo", "11")
       A       ifIndex.1  setScratchpad(Global,        "foo", "22")
       A       ifIndex.1  getScratchpad(PolicyElement, "foo", val) --> 11
       A       ifIndex.1  getScratchpad(Global,        "foo", val) --> 22

       Constants

       The following constants are defined for use with the scratchpad
       functions.  Policy code will be executed in an environment where the
       following constants are declared.  (Note that these constant
       declarations will not be visible in the policyCondition or
       policyAction MIB objects.)

       Although these declarations are expressed here as C 'const's, the
       'const' construct itself is not available to be used inside of policy
       code.

       // Scratchpad Constants

       // Values of scope
       const integer Global           = 0;
       const integer Policy           = 1;
       const integer PolicyElement    = 2;

       // Values of storageType
       const integer Volatile         = 0;
       const integer NonVolatile      = 1;

    8.2.8.  setScratchpad()

          setScratchpad(integer scope, string varName [, string value,
                        integer storageType, integer freeOnException ])

             The setScratchpad function stores a value that can be retrieved
             even after this policy execution code exits.

             The value of 'scope' controls which policy/element combinations
             can retrieve this 'varName'/'value' pair.  The options for
             'scope' are Global, Policy, and PolicyElement.

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             'varName' is a string used to identify the value.  Subsequent
             retrievals of the same 'varName' in the proper scope will
             return the value stored.  Note that the namespace for 'varName'
             is distinct for each scope.  'varName' is case sensitive.

             'value' is a string containing the value to be stored.
             ToString(value) is called on 'value' to convert it to a string
             before storage.

             If the 'value' argument is missing, the 'varName' in scope
             'scope' will be deleted if it exists.

             If the optional 'storageType' argument is present and is equal
             to the constant 'Volatile', then this variable must be deleted
             on a reboot.  If it is equal to 'NonVolatile', then this
             variable should be stored in non-volatile storage, where it
             will be available after a reboot.  If the 'storageType'
             argument is not present, the variable will be volatile and will
             be erased on reboot.  'storageType' may not be present if the
             'value' argument is not present.  If the variable already
             existed, its previous storageType is updated according to the
             current 'storageType' argument.

             If the optional 'freeOnException' argument is present and equal
             to 1, the agent will free this variable if, later in the same
             script invocation, this script dies with a run-time exception
             or by a call to fail().  (Note that this does not apply to
             exceptions experienced in subsequent invocations of the
             script.)

    8.2.9.  getScratchpad()

          integer getScratchpad(integer scope, string varName,
                                string &value)

             The getScratchpad function allows the retrieval of values that
             were stored previously in this execution context or in other
             execution contexts.  The value of 'scope' controls which
             execution contexts can pass a value to this execution context.
             The options for 'scope' are Global, Policy, and PolicyElement.

             'varName' is a string used to identify the value.  Subsequent
             retrievals of the same 'varName' in the proper scope will
             return the value stored.  Note that the namespace for varName
             is distinct for each scope.  As a result, getScratchpad cannot
             force access to a variable in an inaccessible scope; it can
             only retrieve variables by referencing the proper scope in
             which they were set.  'varName' is case sensitive.

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             On successful return, 'value' will be set to the value that was
             previously stored; otherwise, 'value' will not be modified.

             This function returns 1 if a value was previously stored and 0
             otherwise.

    8.2.10.  signalError()

       The signalError() function is used by the script to indicate to a
       management station that it is experiencing abnormal behavior.
       signalError() turns on the conditionUserSignal(3) or
       actionUserSignal(5) bit in the associated pmTrackingPEInfo object
       (subsequent calls to signalError() have no additional effect).  This
       bit is initially cleared at the beginning of each execution.  If,
       upon a subsequent execution, the script finishes without calling
       signalError, the bit will be cleared.

          signalError()

             The signalException function takes no arguments and returns no
             value.

    8.2.11.  defer()

       Precedence groups enforce the rule that for each element, of the
       ready policies that match the condition, only the one with the
       highest precedence value will be active.  Unfortunately, once the
       winning policy has been selected and the action begins running,
       situations can occur in which the policy script determines that it
       cannot complete its task.  In many such cases, it is desirable that
       the next runner-up ready policy be executed.  In the previous
       example, it would be desirable that at least bronze behavior be
       configured if gold is appropriate but gold isn't possible.

       When a policy defers, it exits, and the ready, condition-matching
       policy with the next-highest precedence is immediately run.  Because
       this might also defer, the execution environment must remember where
       it is in the precedence chain so that it can continue going down the
       chain until an action completes without deferring, or until no
       policies are left in the precedence group.  Once a policy finishes
       successfully, the next iteration will begin at the top of the
       precedence chain.

       There are two ways to defer.  A script can exit by calling fail() and
       specify that it should defer immediately.  Alternately, a script can
       instruct the execution environment to defer automatically in the
       event of a run-time exception.

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          defer(integer deferOnRTE)

             The defer function changes the run-time exception behavior of a
             script.  By default, a script will not defer when it encounters
             an RTE.  If defer(1) is called, the exit behavior is changed so
             that the script will defer when it is terminated due to an RTE.
             If defer(0) is called, the script is reset to its default
             behavior and will not defer.

             Note that calling defer doesn't cause the script to exit.
             Defer only changes the default behavior if an RTE occurs later
             in this invocation.

    8.2.12.  fail()

          fail(integer defer, integer free [, string message] )

             The fail function causes the script to optionally perform
             certain functions and then exit.

             If 'defer' is 1, this script will defer to the next lower
             precedence ready policy in the same precedence group whose
             condition matches.  If 'defer' isn't 1, it will not defer.
             Note that if a condition defers, it is functionally equivalent
             to the condition returning false.

             If 'free' is 1, certain registered resources will be freed.
             If, earlier in this script invocation, any rows were created by
             createRow with the 'freeOnException' option, the execution
             environment will set the RowStatus of each row to 'destroy' to
             delete the row.  Further, if earlier in this script invocation
             any scratchpad variables were created or modified with the
             'freeOnException' option, they will be deleted.

             If the optional 'message' argument is present, it will be
             logged to the debugging table if pmPolicyDebugging is turned on
             for this policy.

             This function does not return.  Instead, the script will
             terminate.

    8.2.13.  getParameters()

       From time to time, policy scripts may be parameterized so that they
       are supplied with one or more parameters (e.g., site-specific
       constants).  These parameters may be installed in the
       pmPolicyParameters object and are accessible to the script via the
       getParameters() function.  If it is necessary for multiple parameters

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       to be passed to the script, the script can choose whatever
       encoding/delimiting mechanism is most appropriate so that the
       multiple parameters can be stored in the associated instance of
       pmPolicyParameters.

          string getParameters()

             The getParameters function takes no arguments.  It returns a
             string containing the value of the pmPolicyParameters object
             for the running policy.

       For example, if a policy is to apply to "slow speed interfaces" and
       the cutoff point for slow speed should be parameterized, the policy
       filter should be:

          getVar("ifSpeed.$*") == getParameters()

       In this example, one can store the string "128000" in the policy's
       pmPolicyParameters object to cause this policy to act on all 128 Kbps
       interfaces.

    8.3.  Utility Library Functions

       Utility Library Functions are provided to enable more efficient
       policy scripts.

    8.3.1.  regexp()

          integer regexp(string pattern, string str,
                         integer case [, string &match])

             regexp searches 'str' for matches to the regular expression
             given in `pattern`.  regexp uses the POSIX extended regular
             expressions defined in POSIX 1003.2.

             If `case` is 0, the search will be case insensitive; otherwise,
             it will be case sensitive.

             If a match is found, 1 is returned, otherwise 0 is returned.

             If the optional argument 'match' is provided and a match is
             found, 'match' will be replaced with the text of the first
             substring of 'str' that matches 'pattern'.  If no match is
             found, it will be unchanged.

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    8.3.2.  regexpReplace()

          string regexpReplace(string pattern, string replacement,
                                string str, integer case)

             regexpReplace searches 'str' for matches to the regular
             expression given in 'pattern', replacing each occurrence of
             matched text with 'replacement'.  regexpReplace uses the POSIX
             extended regular expressions defined in POSIX 1003.2.

             If `case` is 0, the search will be case insensitive; otherwise,
             it will be case sensitive.

             The modified string is returned (it would be the same as the
             original string if no matches were found).

    8.3.3.  oidlen()

          integer oidlen(string oid)

             oidlen returns the number of subidentifiers in 'oid'.  'oid' is
             a string containing an ASCII dotted-decimal representation of
             an object identifier (e.g., "1.3.6.1.2.1.1.1.0").

    8.3.4.  oidncmp()

          integer oidncmp(string oid1, string oid2, integer n)

             Arguments 'oid1' and 'oid2' are strings containing ASCII
             dotted-decimal representations of object identifiers (e.g.,
             "1.3.6.1.2.1.1.1.0").

             oidcmp compares not more than n subidentifiers of 'oid1' and
             'oid2' and returns -1 if 'oid1' is less than 'oid2', 0 if they
             are equal, and 1 if 'oid1' is greater than 'oid2'.

    8.3.5.  inSubtree()

          integer inSubtree(string oid, string prefix)

             Arguments 'oid' and 'prefix' are strings containing ASCII
             dotted-decimal representations of object identifiers (e.g.,
             "1.3.6.1.2.1.1.1.0").

             inSubtree returns 1 if every subidentifier in 'prefix' equals
             the corresponding subidentifier in 'oid', otherwise it returns
             0.  The is equivalent to oidncmp(oid1, prefix, oidlen(prefix))

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             is provided because this is an idiom and because it avoids
             evaluating 'prefix' twice if it is an expression.

    8.3.6.  subid()

          integer subid(string oid, integer n)

             subid returns the value of the nth (starting at zero)
             subidentifier of 'oid'.  'oid' is a string containing an ASCII
             dotted-decimal representation of an object identifier (e.g.,
             "1.3.6.1.2.1.1.1.0").

             If n specifies a subidentifier beyond the length of 'oid', a
             value of -1 is returned.

    8.3.7.  subidWrite()

          integer subidWrite(string oid, integer n, integer subid)

             subidWrite sets the value of the nth (starting at zero)
             subidentifier of 'oid' to 'subid'.  'oid' is a string
             containing an ASCII dotted-decimal representation of an object
             identifier (e.g., "1.3.6.1.2.1.1.1.0").

             If n specifies a subidentifier beyond the length of 'oid', a
             value of -1 is returned.  Note that appending subidentifiers
             can be accomplished with the string concatenation '+' operator.
             If no error occurs, zero is returned.

    8.3.8.  oidSplice()

          string oidSplice(string oid1, integer offset, integer len, string
             oid2)

             oidSplice returns an OID formed by replacing 'len'
             subidentifiers in 'oid1' with all of the subidentifiers from
             'oid2', starting at 'offset' in 'oid1' (the first subidentifier
             is at offset 0).  The OID length will be extended, if
             necessary, if 'offset' + 'len' extends beyond the end of
             'oid1'.  If 'offset' is larger than the length of oid1, then an
             RTE will occur.

             The resulting OID is returned.

             For example:
                 oidSplice("1.3.6.1.2.1", 5, 1, "7")     => "1.3.6.1.2.7"
                 oidSplice("1.3.6.1.2.1", 4, 2, "7.7")   => "1.3.6.1.7.7"
                 oidSplice("1.3.6.1.2.1", 4, 3, "7.7.7") => "1.3.6.1.7.7.7"

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    8.3.9.  parseIndex()

       ParseIndex is provided to make it easy to pull index values from OIDs
       into variables.

          var parseIndex(string oid, integer &index, integer type,
                         integer len)

             parseIndex pulls values from the instance identification
             portion of 'oid', encoded as per Section 7.7, "Mapping of the
             INDEX Clause", of the SMIv2 [2].

             'oid' is the OID to be parsed.

             'index' describes which subid to begin parsing at.  'index'
             will be modified to indicate the subid after the last one
             parsed (even if this points past the last subid).  The first
             subid is index 0.  If any error occurs, 'index' will be set to
             -1 on return.  If the input index is less than 0 or refers past
             the end of the OID, 'index' will be set to -1 on return and the
             function will return 0.

             If 'type' is Integer, 'len' will not be consulted.  The return
             value is the integer value of the next subid.

             If 'type' is String and 'len' is greater than zero, 'len'
             subids will be parsed.  For each subid parsed, the chr() value
             of the subid will be appended to the returned string.  If any
             subid is greater than 255, 'index' will be set to -1 on return,
             and an empty string will be returned.  If there are fewer than
             'len' subids left in 'oid', 'index' will be set to -1 on
             return, but a string will be returned containing a character
             for each subid that was left.

             If 'type' is String and 'len' is zero, the next subid will be
             parsed to find N, the length of the string.  Then, that many
             subids will be parsed.  For each subid parsed, the chr() value
             of the subid will be appended to the returned string.  If any
             subid is greater than 255, 'index' will be set to -1 on return,
             and an empty string will be returned.  If there are fewer than
             N subids left in 'oid', 'index' will be set to -1 on return,
             but a string will be returned containing a character for each
             subid that was left.

             If 'type' is String and 'len' is -1, subids will be parsed
             until the end of 'oid'.  For each subid parsed, the chr() value
             of the subid will be appended to the returned string.  If any

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             subid is greater than 255, 'index' will be set to -1 on return,
             and an empty string will be returned.

             If 'type' is Oid and 'len' is greater than zero, 'len' subids
             will be parsed.  For each subid parsed, the decimal-encoded
             value of the subid will be appended to the returned string,
             with a '.' character appended between each output subid, but
             not after the last subid.  If there are fewer than 'len' subids
             left in 'oid', 'index' will be set to -1 on return, but a
             string will be returned containing an encoding for each subid
             that was left.

             If 'type' is Oid and 'len' is zero, the next subid will be
             parsed to find N, the number of subids to parse.  For each
             subid parsed, the decimal-encoded value of the subid will be
             appended to the returned string, with a '.' character appended
             between each output subid but not after the last subid.  If
             there are fewer than N subids left in 'oid', 'index' will be
             set to -1 on return, but a string will be returned containing
             an encoding for each subid that was left.

             If 'type' is Oid and 'len' is -1, subids will be parsed until
             the end of 'oid'.  For each subid parsed, the decimal-encoded
             value of the subid will be appended to the returned string,
             with a '.' character appended between each output subid, but
             not after the last subid.

       For example, to decode the index component of an instance of the
       ipForward table:

          oid = "ipForwardIfIndex.0.0.0.0.13.0.192.168.1.1";
          index = 11;
          dest   =  parseIndex(oid, index, String, 4);
          proto  =  parseIndex(oid, index, Integer, 0);
          policy =  parseIndex(oid, index, Integer, 0);
          nextHop = parseIndex(oid, index, String, 4);
          // proto and policy now contain integer values
          // dest and nextHop now contain 4 byte IP addresses.  Use
          // stringToDotted to get them to dotted decimal notation:
          // e.g.: stringToDotted(nextHop) => "192.168.1.1"

    8.3.10.  stringToDotted()

       stringToDotted() is provided to encode strings suitable for the index
       portion of an OID or to convert the binary encoding of an IP address
       to a dotted-decimal encoding.

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          string stringToDotted(string value)

             If 'value' is the zero-length string, the zero-length string is
             returned.

             The decimal encoding of the first byte of 'value' is appended
             to the output string.  Then, for each additional byte in
             'value', a '.' is appended to the output string, followed by
             the decimal encoding of the additional byte.

    8.3.11.  integer()

          integer integer(var input)

             integer converts 'input' into an integer by using the rules
             specified for ToInteger(), returning the integer-typed results.

    8.3.12.  string()

          string string(var input)

             string converts 'input' into a string by using the rules
             specified for ToString(), returning the string-typed results.

    8.3.13.  type()

          string type(var variable)

             type returns the type of its argument as either the string
             'String' or the string 'Integer'.

    8.3.14.  chr()

          string chr(integer char)

             Returns a one-character string containing the character
             specified by the ASCII code contained in 'char'.

    8.3.15.  ord()

          integer ord(string str)

             Returns the ASCII value of the first character of 'str'.  This
             function complements chr().

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    8.3.16.  substr()

          string substr(string &str, integer offset
                        [, integer len, string replacement])

             Extracts a substring out of 'str' and returns it.  The first
             octet is at offset 0.  If the offset is negative, the returned
             string starts that far from the end of 'str'.  If 'len' is
             positive, the returned string contains up to 'len' octets, up
             to the end of the string.  If 'len' is omitted, the returned
             string includes everything to the end of 'str'.  If 'len' is
             negative, abs(len) octets are left off the end of the string.

             If a substring is specified that is partly outside the string,
             the part within the string is returned.  If the substring is
             totally outside the string, a zero-length string is produced.

             If the optional 'replacement' argument is included, 'str' is
             modified.  'offset' and 'len' act as above to select a range of
             octets in 'str'.  These octets are replaced with octets from
             'replacement'.  If the replacement string is shorter or longer
             than the number of octets selected, 'str' will shrink or grow,
             respectively.  If 'replacement' is included, the 'len' argument
             must also be included.

             Note that to replace everything from offset to the end of the
             string, substr() should be called as follows:

                substr(str, offset, strlen(str) - offset, replacement)

    8.4.  General Functions

       The following POSIX standard library functions are provided:

           strncmp()
           strncasecmp()
           strlen()
           random()
           sprintf()
           sscanf()

    9.  International String Library

       This library is optional for systems that wish to have support for
       collating (sorting) and verifying equality of international strings
       in a manner that will be least surprising to humans.  International

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       strings are encoded in the UTF-8 transformation format described in
       [14].  This library is registered with the name
       "pmInternationalStringLibrary".

       When verifying equality of international strings in the Unicode
       character set, it is recommended to normalize the strings with the
       stringprep() function before checking for equality.

       When attempting to sort international strings in the Unicode
       character set, normalization should also be performed, but note that
       the result is highly context dependent and hard to implement
       correctly.  Just ordering by Unicode Codepoint Value is in many cases
       not what the end user expects.  See Unicode technical note 9 for more
       information about sorting.

    9.1.  stringprep()

          integer stringprep(string utf8Input, string &utf8Output)

             Performs the Stringprep [13] transformation for appropriate
             comparison of internationalized strings.  The transformation is
             performed on 'utf8Input'; if the transformation finishes
             without error, the resulting string is written to utf8Output.
             The stringprep profile used is specified below in Section 9.
             If it is successful, the function returns 1.

             If the stringprep transformation encounters an error, 0 is
             returned, and the utf8Output parameter remains unchanged.

             For example, to compare UTF8 strings 'one' and 'two':

             if (stringprep(one, a) && stringprep(two, b)){
                 if (a == b){
                    // strings are identical
                 } else {
                    // strings are different
                 }
             } else {
                 // strings couldn't be transformed for comparison
             }

             See Stringprep [13] for more information.

    9.1.1.  Stringprep Profile

       The Stringprep specification [13] describes a framework for preparing
       Unicode text strings in order to increase the likelihood that string
       input and string comparison work in ways that make sense for typical

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       users throughout the world.  Specifications that specify stringprep
       (as this one does) are required to fully specify stringprep's
       processing options by documenting a stringprep profile.

       This profile defines the following, as required by Stringprep:

       - The intended applicability of the profile: internationalized
         network management information.

       - The character repertoire that is the input and output to
         stringprep: Unicode 3.2, as defined in Stringprep [13], Appendix
         A.1.

       - The mapping tables used: Table B.1 from Stringprep [13].

       - Any additional mapping tables specific to the profile: None.

       - The Unicode normalization used: Form KC, as described in Stringprep
         [13].

       - The characters that are prohibited as output: As specified in the
         following tables from Stringprep [13]:

           Table C.2
           Table C.3
           Table C.4
           Table C.5
           Table C.6
           Table C.7
           Table C.8
           Table C.9

       - Bidirectional character handling: not performed.

       - Any additional characters that are prohibited as output:  None.

    9.2.  utf8Strlen()

          integer utf8Strlen(string str)

             Returns the number of UTF-8 characters in 'str', which may be
             less than the number of octets in 'str' if one or more
             characters are multi-byte characters.

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    9.3.  utf8Chr()

          string utf8Chr(integer utf8)

             Returns a one-character string containing the character
             specified by the UTF-8 code contained in 'utf8'.  Although it
             contains only 1 UTF-8 character, the resulting string may be
             more than 1 octet in length.

    9.4.  utf8Ord()

          integer utf8Ord(string str)

             Returns the UTF-8 code-point value of the first character of
             'str'.  Note that the first UTF-8 character in 'str' may be
             more than 1 octet in length.  This function complements chr().

    9.5.  utf8Substr()

          string utf8Substr(string &str, integer offset
                        [, integer len, string replacement])

             Extracts a substring out of 'str' and returns it, keeping track
             of UTF-8 character boundaries and using them, instead of
             octets, as the basis for offset and length calculations.  The
             first character is at offset 0.  If offset is negative, the
             returned string starts that far from the end of 'str'.  If
             'len' is positive, the returned string contains up to 'len'
             characters, up to the end of the string.  If 'len' is omitted,
             the returned string includes everything to the end of 'str'.
             If 'len' is negative, abs(len) characters are left off the end
             of the string.

             If you specify a substring that is partly outside the string,
             the part within the string is returned.  If the substring is
             totally outside the string, a zero-length string is produced.

             If the optional 'replacement' argument is included, 'str' is
             modified.  'offset' and 'len' act as above to select a range of
             characters in 'str'.  These characters are replaced with
             characters from 'replacement'.  If the replacement string is
             shorter or longer than the number of characters selected, 'str'
             will shrink or grow, respectively.  If 'replacement' is
             included, the 'len' argument must also be included.

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             Note that to replace everything from offset to the end of the
             string, substr() should be called as follows:

                substr(str, offset, strlen(str) - offset, replacement)

    10.  Schedule Table

       This table is an adapted form of the policyTimePeriodCondition class
       defined in the Policy Core Information Model, RFC 3060 [18].  Some of
       the objects describing a schedule are expressed in formats defined in
       the iCalendar specification [15].

       The policy schedule table allows control over when a valid policy
       will be ready, based on the date and time.

       A policy's pmPolicySchedule variable refers to a group of one or more
       schedules in the schedule table.  At any given time, if any of these
       schedules are active, the policy will be ready (assuming that it is
       enabled and thus valid), and its conditions and actions will be
       executed, as appropriate.  At times when none of these schedules are
       active, the policy will not be ready and will have no effect.  A
       policy will always be ready if its pmPolicySchedule variable is 0.
       If a policy has a non-zero pmPolicySchedule that doesn't refer to a
       group that includes an active schedule, then the policy will not be
       ready, even if this is due to a misconfiguration of the
       pmPolicySchedule object or the pmSchedTable.

       A policy that is controlled by a schedule group immediately executes
       its policy condition (and conditionally the policyAction) when the
       schedule group becomes active, periodically re-executing these
       scripts as appropriate until the schedule group becomes inactive
       (i.e., all schedules are inactive).

       An individual schedule item is active at those times that match all
       the variables that define the schedule:  pmSchedTimePeriod,
       pmSchedMonth, pmSchedDay, pmSchedWeekDay, and pmSchedTimeOfDay.  It
       is possible to specify multiple values for each schedule item.  This
       provides a mechanism for defining complex schedules.  For example, a
       schedule that is active the entire workday each weekday could be
       defined.

       Months, days, and weekdays are specified by using the objects
       pmSchedMonth, pmSchedDay, and pmSchedWeekDay of type BITS.  Setting
       multiple bits in these objects causes an OR operation.  For example,
       setting the bits monday(1) and friday(5) in pmSchedWeekDay restricts
       the schedule to Mondays and Fridays.

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       The matched times for pmSchedTimePeriod, pmSchedMonth, pmSchedDay
       pmSchedWeekDay, and pmSchedTimeOfDay are ANDed together to determine
       the time periods when the schedule will be active; in other words,
       the schedule is only active for those times when ALL of these
       schedule attributes match.  For example, a schedule with an overall
       validity range of January 1, 2000, through December 31, 2000; a month
       mask that selects March and April; a day-of-the-week mask that
       selects Fridays; and a time-of-day range of 0800 through 1600 would
       represent the following time periods:

          Friday, March  5, 2000, from 0800 through 1600
          Friday, March 12, 2000, from 0800 through 1600
          Friday, March 19, 2000, from 0800 through 1600
          Friday, March 26, 2000, from 0800 through 1600
          Friday, April  2, 2000, from 0800 through 1600
          Friday, April  9, 2000, from 0800 through 1600
          Friday, April 16, 2000, from 0800 through 1600
          Friday, April 23, 2000, from 0800 through 1600
          Friday, April 30, 2000, from 0800 through 1600

       Wildcarding of schedule attributes of type BITS is achieved by
       setting all bits to one.

       It is possible to define schedules that will never cause a policy to
       be activated.  For example, one can define a schedule that should be
       active on February 31st.

    11.  Definitions

    POLICY-BASED-MANAGEMENT-MIB DEFINITIONS ::= BEGIN
    IMPORTS
        MODULE-IDENTITY, OBJECT-TYPE, NOTIFICATION-TYPE,
        Counter32, Gauge32, Unsigned32,
        mib-2                                       FROM SNMPv2-SMI
        RowStatus, RowPointer, TEXTUAL-CONVENTION,
        DateAndTime, StorageType                    FROM SNMPv2-TC
        MODULE-COMPLIANCE, OBJECT-GROUP,
        NOTIFICATION-GROUP                          FROM SNMPv2-CONF
        SnmpAdminString                             FROM SNMP-FRAMEWORK-MIB;

    --  Policy-Based Management MIB

    pmMib MODULE-IDENTITY
        LAST-UPDATED "200502070000Z"  -- February 7, 2005
        ORGANIZATION "IETF SNMP Configuration Working Group"
        CONTACT-INFO
            "

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            Steve Waldbusser
            Phone: +1-650-948-6500
            Fax:   +1-650-745-0671
            Email: waldbusser@nextbeacon.com

            Jon Saperia (WG Co-chair)
            JDS Consulting, Inc.
            84 Kettell Plain Road.
            Stow MA 01775
            USA
            Phone: +1-978-461-0249
            Fax:   +1-617-249-0874
            Email: saperia@jdscons.com

            Thippanna Hongal
            Riverstone Networks, Inc.
            5200 Great America Parkway
            Santa Clara, CA, 95054
            USA

            Phone: +1-408-878-6562
            Fax:   +1-408-878-6501
            Email: hongal@riverstonenet.com

            David Partain (WG Co-chair)
            Postal: Ericsson AB
                    P.O. Box 1248
                    SE-581 12 Linkoping
                    Sweden
            Tel: +46 13 28 41 44
            E-mail: David.Partain@ericsson.com

            Any questions or comments about this document can also be
            directed to the working group at snmpconf@snmp.com."
        DESCRIPTION
            "The MIB module for policy-based configuration of SNMP
            infrastructures.

            Copyright (C) The Internet Society (2005).  This version of
            this MIB module is part of RFC 4011; see the RFC itself for
            full legal notices."

        REVISION "200502070000Z"    -- February 7, 2005
        DESCRIPTION
            "The original version of this MIB, published as RFC4011."
        ::= { mib-2 124 }

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    PmUTF8String ::= TEXTUAL-CONVENTION
        STATUS       current
        DESCRIPTION
            "An octet string containing information typically in
            human-readable form.

            To facilitate internationalization, this
            information is represented by using the ISO/IEC
            IS 10646-1 character set, encoded as an octet
            string using the UTF-8 transformation format
            described in RFC 3629.

            As additional code points are added by
            amendments to the 10646 standard from time
            to time, implementations must be prepared to
            encounter any code point from 0x00000000 to
            0x10FFFF.  Byte sequences that do not
            correspond to the valid UTF-8 encoding of a
            code point or that are outside this range are
            prohibited.

            The use of control codes should be avoided.

            When it is necessary to represent a newline,
            the control code sequence CR LF should be used.

            For code points not directly supported by user
            interface hardware or software, an alternative
            means of entry and display, such as hexadecimal,
            may be provided.

            For information encoded in 7-bit US-ASCII,
            the UTF-8 encoding is identical to the
            US-ASCII encoding.

            UTF-8 may require multiple bytes to represent a
            single character/code point; thus, the length
            of this object in octets may be different from
            the number of characters encoded.  Similarly,
            size constraints refer to the number of encoded
            octets, not the number of characters represented
            by an encoding.

            Note that when this TC is used for an object
            used or envisioned to be used as an index, then
            a SIZE restriction MUST be specified so that the
            number of sub-identifiers for any object instance
            does not exceed the limit of 128, as defined by

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            RFC 3416.

            Note that the size of PmUTF8String object is
            measured in octets, not characters."
           SYNTAX       OCTET STRING (SIZE (0..65535))

    -- The policy table

    pmPolicyTable OBJECT-TYPE
        SYNTAX      SEQUENCE OF PmPolicyEntry
        MAX-ACCESS  not-accessible
        STATUS      current
        DESCRIPTION
            "The policy table.  A policy is a pairing of a
            policyCondition and a policyAction that is used to apply the
            action to a selected set of elements."
        ::= { pmMib 1 }

    pmPolicyEntry OBJECT-TYPE
        SYNTAX      PmPolicyEntry
        MAX-ACCESS  not-accessible
        STATUS      current
        DESCRIPTION
            "An entry in the policy table representing one policy."
        INDEX { pmPolicyAdminGroup, pmPolicyIndex }
        ::= { pmPolicyTable 1 }

    PmPolicyEntry ::= SEQUENCE {
        pmPolicyAdminGroup            PmUTF8String,
        pmPolicyIndex                 Unsigned32,
        pmPolicyPrecedenceGroup       PmUTF8String,
        pmPolicyPrecedence            Unsigned32,
        pmPolicySchedule              Unsigned32,
        pmPolicyElementTypeFilter     PmUTF8String,
        pmPolicyConditionScriptIndex  Unsigned32,
        pmPolicyActionScriptIndex     Unsigned32,
        pmPolicyParameters            OCTET STRING,
        pmPolicyConditionMaxLatency   Unsigned32,
        pmPolicyActionMaxLatency      Unsigned32,
        pmPolicyMaxIterations         Unsigned32,
        pmPolicyDescription           PmUTF8String,
        pmPolicyMatches               Gauge32,
        pmPolicyAbnormalTerminations  Gauge32,
        pmPolicyExecutionErrors       Counter32,
        pmPolicyDebugging             INTEGER,
        pmPolicyAdminStatus           INTEGER,
        pmPolicyStorageType           StorageType,
        pmPolicyRowStatus             RowStatus

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    }

    pmPolicyAdminGroup OBJECT-TYPE
        SYNTAX      PmUTF8String (SIZE(0..32))
        MAX-ACCESS  not-accessible
        STATUS      current
        DESCRIPTION
            "An administratively assigned string that can be used to group
            policies for convenience, for readability, or to simplify
            configuration of access control.

            The value of this string does not affect policy processing in
            any way.  If grouping is not desired or necessary, this object
            may be set to a zero-length string."
        ::= { pmPolicyEntry 1 }

    pmPolicyIndex OBJECT-TYPE
        SYNTAX      Unsigned32 (1..4294967295)
        MAX-ACCESS  not-accessible
        STATUS      current
        DESCRIPTION
             "A unique index for this policy entry, unique among all
             policies regardless of administrative group."
        ::= { pmPolicyEntry 2 }

    pmPolicyPrecedenceGroup OBJECT-TYPE
        SYNTAX      PmUTF8String (SIZE (0..32))
        MAX-ACCESS  read-create
        STATUS      current
        DESCRIPTION
            "An administratively assigned string that is used to group
            policies.  For each element, only one policy in the same
            precedence group may be active on that element.  If multiple
            policies would be active on an element (because their
            conditions return non-zero), the execution environment will
            only allow the policy with the highest value of
            pmPolicyPrecedence to be active.

            All values of this object must have been successfully
            transformed by Stringprep RFC 3454.  Management stations
            must perform this translation and must only set this object to
            string values that have been transformed."
        ::= { pmPolicyEntry 3 }

    pmPolicyPrecedence OBJECT-TYPE
        SYNTAX      Unsigned32 (0..65535)
        MAX-ACCESS  read-create
        STATUS      current

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        DESCRIPTION
            "If, while checking to see which policy conditions match an
            element, 2 or more ready policies in the same precedence group
            match the same element, the pmPolicyPrecedence object provides
            the rule to arbitrate which single policy will be active on
            'this element'.  Of policies in the same precedence group, only
            the ready and matching policy with the highest precedence
            value (e.g., 2 is higher than 1) will have its policy action
            periodically executed on 'this element'.

            When a policy is active on an element but the condition ceases
            to match the element, its action (if currently running) will
            be allowed to finish and then the condition-matching ready
            policy with the next-highest precedence will immediately
            become active (and have its action run immediately).  If the
            condition of a higher-precedence ready policy suddenly begins
            matching an element, the previously-active policy's action (if
            currently running) will be allowed to finish and then the
            higher precedence policy will immediately become active.  Its
            action will run immediately, and any lower-precedence matching
            policy will not be active anymore.

            In the case where multiple ready policies share the highest
            value, it is an implementation-dependent matter as to which
            single policy action will be chosen.

            Note that if it is necessary to take certain actions after a
            policy is no longer active on an element, these actions should
            be included in a lower-precedence policy that is in the same
            precedence group."
        ::= { pmPolicyEntry 4 }

    pmPolicySchedule OBJECT-TYPE
        SYNTAX      Unsigned32 (1..4294967295)
        MAX-ACCESS  read-create
        STATUS      current
        DESCRIPTION
             "This policy will be ready if any of the associated schedule
             entries are active.

             If the value of this object is 0, this policy is always
             ready.

             If the value of this object is non-zero but doesn't
             refer to a schedule group that includes an active schedule,
             then the policy will not be ready, even if this is due to a
             misconfiguration of this object or the pmSchedTable."
        ::= { pmPolicyEntry 5 }

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    pmPolicyElementTypeFilter OBJECT-TYPE
        SYNTAX      PmUTF8String (SIZE (0..128))
        MAX-ACCESS  read-create
        STATUS      current
        DESCRIPTION
            "This object specifies the element types for which this policy
            can be executed.

            The format of this object will be a sequence of
            pmElementTypeRegOIDPrefix values, encoded in the following
            BNF form:

            elementTypeFilter:   oid [ ';' oid ]*
                          oid:   subid [ '.' subid ]*
                        subid:   '0' | decimal_constant

            For example, to register for the policy to be run on all
            interface elements, the 'ifEntry' element type will be
            registered as '1.3.6.1.2.1.2.2.1'.

            If a value is included that does not represent a registered
            pmElementTypeRegOIDPrefix, then that value will be ignored."
        ::= { pmPolicyEntry 6 }

    pmPolicyConditionScriptIndex OBJECT-TYPE
        SYNTAX      Unsigned32 (1..4294967295)
        MAX-ACCESS  read-only
        STATUS      current
        DESCRIPTION
             "A pointer to the row or rows in the pmPolicyCodeTable that
             contain the condition code for this policy.  When a policy
             entry is created, a pmPolicyCodeIndex value unused by this
             policy's adminGroup will be assigned to this object.

             A policy condition is one or more PolicyScript statements
             that result(s) in a boolean value that represents whether
             an element is a member of a set of elements upon which an
             action is to be performed.  If a policy is ready and the
             condition returns true for an element of a proper element
             type, and if no higher-precedence policy should be active,
             then the policy is active on that element.

             Condition evaluation stops immediately when any run-time
             exception is detected, and the policyAction is not executed.

             The policyCondition is evaluated for various elements.  Any
             element for which the policyCondition returns any nonzero value
             will match the condition and will have the associated

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             policyAction executed on that element unless a
             higher-precedence policy in the same precedence group also
             matches 'this element'.

             If the condition object is empty (contains no code) or
             otherwise does not return a value, the element will not be
             matched.

             When this condition is executed, if SNMP requests are made to
             the local system and secModel/secName/secLevel aren't
             specified, access to objects is under the security
             credentials of the requester who most recently modified the
             associated pmPolicyAdminStatus object.  If SNMP requests are
             made in which secModel/secName/secLevel are specified, then
             the specified credentials are retrieved from the local
             configuration datastore only if VACM is configured to
             allow access to the requester who most recently modified the
             associated pmPolicyAdminStatus object.  See the Security
             Considerations section for more information."
        ::= { pmPolicyEntry 7 }

    pmPolicyActionScriptIndex OBJECT-TYPE
        SYNTAX      Unsigned32 (1..4294967295)
        MAX-ACCESS  read-only
        STATUS      current
        DESCRIPTION
             "A pointer to the row or rows in the pmPolicyCodeTable that
             contain the action code for this policy.  When a policy entry
             is created, a pmPolicyCodeIndex value unused by this policy's
             adminGroup will be assigned to this object.

             A PolicyAction is an operation performed on a
             set of elements for which the policy is active.

             Action evaluation stops immediately when any run-time
             exception is detected.

             When this condition is executed, if SNMP requests are made to
             the local system and secModel/secName/secLevel aren't
             specified, access to objects is under the security
             credentials of the requester who most recently modified the
             associated pmPolicyAdminStatus object.  If SNMP requests are
             made in which secModel/secName/secLevel are specified, then
             the specified credentials are retrieved from the local
             configuration datastore only if VACM is configured to
             allow access to the requester who most recently modified the
             associated pmPolicyAdminStatus object.  See the Security
             Considerations section for more information."

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        ::= { pmPolicyEntry 8 }

    pmPolicyParameters OBJECT-TYPE
        SYNTAX      OCTET STRING (SIZE (0..65535))
        MAX-ACCESS  read-create
        STATUS      current
        DESCRIPTION
            "From time to time, policy scripts may seek one or more
            parameters (e.g., site-specific constants).  These parameters
            may be installed with the script in this object and are
            accessible to the script via the getParameters() function.  If
            it is necessary for multiple parameters to be passed to the
            script, the script can choose whatever encoding/delimiting
            mechanism is most appropriate."
        ::= { pmPolicyEntry 9 }

    pmPolicyConditionMaxLatency OBJECT-TYPE
        SYNTAX      Unsigned32 (0..2147483647)
        UNITS       "milliseconds"
        MAX-ACCESS  read-create
        STATUS      current
        DESCRIPTION
            "Every element under the control of this agent is
            re-checked periodically to see whether it is under control
            of this policy by re-running the condition for this policy.
            This object lets the manager control the maximum amount of
            time that may pass before an element is re-checked.

            In other words, in any given interval of this duration, all
            elements must be re-checked.  Note that how the policy agent
            schedules the checking of various elements within this
            interval is an implementation-dependent matter.
            Implementations may wish to re-run a condition more
            quickly if they note a change to the role strings for an
            element."
        ::= { pmPolicyEntry 10 }

    pmPolicyActionMaxLatency OBJECT-TYPE
        SYNTAX      Unsigned32 (0..2147483647)
        UNITS       "milliseconds"
        MAX-ACCESS  read-create
        STATUS      current
        DESCRIPTION
            "Every element that matches this policy's condition and is
            therefore under control of this policy will have this policy's
            action executed periodically to ensure that the element
            remains in the state dictated by the policy.
            This object lets the manager control the maximum amount of

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            time that may pass before an element has the action run on
            it.

            In other words, in any given interval of this duration, all
            elements under control of this policy must have the action run
            on them.  Note that how the policy agent schedules the policy
            action on various elements within this interval is an
            implementation-dependent matter."
        ::= { pmPolicyEntry 11 }

    pmPolicyMaxIterations OBJECT-TYPE
        SYNTAX      Unsigned32
        MAX-ACCESS  read-create
        STATUS      current
        DESCRIPTION
            "If a condition or action script iterates in loops too many
            times in one invocation, the execution environment may
            consider it in an infinite loop or otherwise not acting
            as intended and may be terminated by the execution
            environment.  The execution environment will count the
            cumulative number of times all 'for' or 'while' loops iterated
            and will apply a threshold to determine when to terminate the
            script.  What threshold the execution environment uses is an
            implementation-dependent manner, but the value of
            this object SHOULD be the basis for choosing the threshold for
            each script.  The value of this object represents a
            policy-specific threshold and can be tuned for policies of
            varying workloads.  If this value is zero, no
            threshold will be enforced except for any
            implementation-dependent maximum.  Regardless of this value,
            the agent is allowed to terminate any script invocation that
            exceeds a local CPU or memory limitation.

            Note that the condition and action invocations are tracked
            separately."
        ::= { pmPolicyEntry 12 }

    pmPolicyDescription OBJECT-TYPE
        SYNTAX      PmUTF8String
        MAX-ACCESS  read-create
        STATUS      current
        DESCRIPTION
             "A description of this rule and its significance, typically
             provided by a human."
        ::= { pmPolicyEntry 13 }

    pmPolicyMatches OBJECT-TYPE
        SYNTAX      Gauge32

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        UNITS       "elements"
        MAX-ACCESS  read-only
        STATUS      current
        DESCRIPTION
             "The number of elements that, in their most recent execution
             of the associated condition, were matched by the condition."
        ::= { pmPolicyEntry 14 }

    pmPolicyAbnormalTerminations OBJECT-TYPE
        SYNTAX      Gauge32
        UNITS       "elements"
        MAX-ACCESS  read-only
        STATUS      current
        DESCRIPTION
             "The number of elements that, in their most recent execution
             of the associated condition or action, have experienced a
             run-time exception and terminated abnormally.  Note that if a
             policy was experiencing a run-time exception while processing
             a particular element but runs normally on a subsequent
             invocation, this number can decline."
        ::= { pmPolicyEntry 15 }

    pmPolicyExecutionErrors OBJECT-TYPE
        SYNTAX      Counter32
        UNITS       "errors"
        MAX-ACCESS  read-only
        STATUS      current
        DESCRIPTION
             "The total number of times that execution of this policy's
             condition or action has been terminated due to run-time
             exceptions."
        ::= { pmPolicyEntry 16 }

    pmPolicyDebugging OBJECT-TYPE
        SYNTAX      INTEGER {
                        off(1),
                        on(2)
                    }
        MAX-ACCESS  read-create
        STATUS      current
        DESCRIPTION
             "The status of debugging for this policy.  If this is turned
             on(2), log entries will be created in the pmDebuggingTable
             for each run-time exception that is experienced by this
             policy."
        DEFVAL { off }
        ::= { pmPolicyEntry 17 }

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    pmPolicyAdminStatus OBJECT-TYPE
        SYNTAX      INTEGER {
                        disabled(1),
                        enabled(2),
                        enabledAutoRemove(3)
                    }
        MAX-ACCESS  read-create
        STATUS      current
        DESCRIPTION
             "The administrative status of this policy.

             The policy will be valid only if the associated
             pmPolicyRowStatus is set to active(1) and this object is set
             to enabled(2) or enabledAutoRemove(3).

             If this object is set to enabledAutoRemove(3), the next time
             the associated schedule moves from the active state to the
             inactive state, this policy will immediately be deleted,
             including any associated entries in the pmPolicyCodeTable.

             The following related objects may not be changed unless this
             object is set to disabled(1):
                 pmPolicyPrecedenceGroup, pmPolicyPrecedence,
                 pmPolicySchedule, pmPolicyElementTypeFilter,
                 pmPolicyConditionScriptIndex, pmPolicyActionScriptIndex,
                 pmPolicyParameters, and any pmPolicyCodeTable row
                 referenced by this policy.
             In order to change any of these parameters, the policy must
             be moved to the disabled(1) state, changed, and then
             re-enabled.

             When this policy moves to either enabled state from the
             disabled state, any cached values of policy condition must be
             erased, and any Policy or PolicyElement scratchpad values for
             this policy should be removed.  Policy execution will begin by
             testing the policy condition on all appropriate elements."
        ::= { pmPolicyEntry 18 }

    pmPolicyStorageType OBJECT-TYPE
        SYNTAX      StorageType
        MAX-ACCESS  read-create
        STATUS      current
        DESCRIPTION
            "This object defines whether this policy and any associated
             entries in the pmPolicyCodeTable are kept in volatile storage
             and lost upon reboot or if this row is backed up by
             non-volatile or permanent storage.

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             If the value of this object is 'permanent', the values for
             the associated pmPolicyAdminStatus object must remain
             writable."
        ::= { pmPolicyEntry 19 }

    pmPolicyRowStatus OBJECT-TYPE
        SYNTAX      RowStatus
        MAX-ACCESS  read-create
        STATUS      current
        DESCRIPTION
             "The row status of this pmPolicyEntry.

             The status may not be set to active if any of the related
             entries in the pmPolicyCode table do not have a status of
             active or if any of the objects in this row are not set to
             valid values.  Only the following objects may be modified
             while in the active state:
                 pmPolicyParameters
                 pmPolicyConditionMaxLatency
                 pmPolicyActionMaxLatency
                 pmPolicyDebugging
                 pmPolicyAdminStatus

             If this row is deleted, any associated entries in the
             pmPolicyCodeTable will be deleted as well."
        ::= { pmPolicyEntry 20 }

    -- Policy Code Table

    pmPolicyCodeTable OBJECT-TYPE
        SYNTAX      SEQUENCE OF PmPolicyCodeEntry
        MAX-ACCESS  not-accessible
        STATUS      current
        DESCRIPTION
            "The pmPolicyCodeTable stores the code for policy conditions and
            actions.

            An example of the relationships between the code table and the
            policy table follows:

            pmPolicyTable
                AdminGroup  Index   ConditionScriptIndex  ActionScriptIndex
            A   ''          1       1                     2
            B   'oper'      1       1                     2
            C   'oper'      2       3                     4

            pmPolicyCodeTable
            AdminGroup  ScriptIndex  Segment    Note

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            ''          1            1          Filter for policy A
            ''          2            1          Action for policy A
            'oper'      1            1          Filter for policy B
            'oper'      2            1          Action 1/2 for policy B
            'oper'      2            2          Action 2/2 for policy B
            'oper'      3            1          Filter for policy C
            'oper'      4            1          Action for policy C

            In this example, there are 3 policies: 1 in the '' adminGroup,
            and 2 in the 'oper' adminGroup.  Policy A has been assigned
            script indexes 1 and 2 (these script indexes are assigned out of
            a separate pool per adminGroup), with 1 code segment each for
            the filter and the action.  Policy B has been assigned script
            indexes 1 and 2 (out of the pool for the 'oper' adminGroup).
            While the filter has 1 segment, the action is longer and is
            loaded into 2 segments.  Finally, Policy C has been assigned
            script indexes 3 and 4, with 1 code segment each for the filter
            and the action."
        ::= { pmMib 2 }

    pmPolicyCodeEntry OBJECT-TYPE
        SYNTAX      PmPolicyCodeEntry
        MAX-ACCESS  not-accessible
        STATUS      current
        DESCRIPTION
            "An entry in the policy code table representing one code
            segment.  Entries that share a common AdminGroup/ScriptIndex
            pair make up a single script.  Valid values of ScriptIndex are
            retrieved from pmPolicyConditionScriptIndex and
            pmPolicyActionScriptIndex after a pmPolicyEntry is
            created.  Segments of code can then be written to this table
            with the learned ScriptIndex values.

            The StorageType of this entry is determined by the value of
            the associated pmPolicyStorageType.

            The pmPolicyAdminGroup element of the index represents the
            administrative group of the policy of which this code entry is
            a part."
        INDEX { pmPolicyAdminGroup, pmPolicyCodeScriptIndex,
                pmPolicyCodeSegment }
        ::= { pmPolicyCodeTable 1 }

    PmPolicyCodeEntry ::= SEQUENCE {
        pmPolicyCodeScriptIndex    Unsigned32,
        pmPolicyCodeSegment        Unsigned32,
        pmPolicyCodeText           PmUTF8String,
        pmPolicyCodeStatus         RowStatus

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    }

    pmPolicyCodeScriptIndex OBJECT-TYPE
        SYNTAX      Unsigned32 (1..4294967295)
        MAX-ACCESS  not-accessible
        STATUS      current
        DESCRIPTION
             "A unique index for each policy condition or action.  The code
             for each such condition or action may be composed of multiple
             entries in this table if the code cannot fit in one entry.
             Values of pmPolicyCodeScriptIndex may not be used unless
             they have previously been assigned in the
             pmPolicyConditionScriptIndex or pmPolicyActionScriptIndex
             objects."
        ::= { pmPolicyCodeEntry 1 }

    pmPolicyCodeSegment OBJECT-TYPE
        SYNTAX      Unsigned32 (1..4294967295)
        MAX-ACCESS  not-accessible
        STATUS      current
        DESCRIPTION
             "A unique index for each segment of a policy condition or
             action.

             When a policy condition or action spans multiple entries in
             this table, the code of that policy starts from the
             lowest-numbered segment and continues with increasing segment
             values until it ends with the highest-numbered segment."
        ::= { pmPolicyCodeEntry 2 }

    pmPolicyCodeText OBJECT-TYPE
        SYNTAX      PmUTF8String (SIZE (1..1024))
        MAX-ACCESS  read-create
        STATUS      current
        DESCRIPTION
             "A segment of policy code (condition or action).  Lengthy
             Policy conditions or actions may be stored in multiple
             segments in this table that share the same value of
             pmPolicyCodeScriptIndex.  When multiple segments are used, it
             is recommended that each segment be as large as is practical.

             Entries in this table are associated with policies by values
             of the pmPolicyConditionScriptIndex and
             pmPolicyActionScriptIndex objects.  If the status of the
             related policy is active, then this object may not be
             modified."
        ::= { pmPolicyCodeEntry 3 }

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    pmPolicyCodeStatus OBJECT-TYPE
        SYNTAX      RowStatus
        MAX-ACCESS  read-create
        STATUS      current
        DESCRIPTION
             "The status of this code entry.

             Entries in this table are associated with policies by values
             of the pmPolicyConditionScriptIndex and
             pmPolicyActionScriptIndex objects.  If the status of the
             related policy is active, then this object can not be
             modified (i.e., deleted or set to notInService), nor may new
             entries be created.

             If the status of this object is active, no objects in this
             row may be modified."
        ::= { pmPolicyCodeEntry 4 }

    -- Element Type Registration Table

    pmElementTypeRegTable OBJECT-TYPE
        SYNTAX      SEQUENCE OF PmElementTypeRegEntry
        MAX-ACCESS  not-accessible
        STATUS      current
        DESCRIPTION
            "A registration table for element types managed by this
            system.

            The Element Type Registration table allows the manager to
            learn what element types are being managed by the system and
            to register new types, if necessary.  An element type is
            registered by providing the OID of an SNMP object (i.e.,
            without the instance).  Each SNMP instance that exists under
            that object is a distinct element.  The index of the element is
            the index part of the discovered OID.  This index will be
            supplied to policy conditions and actions so that this code
            can inspect and configure the element.

            For example, this table might contain the following entries.
            The first three are agent-installed, and the 4th was
            downloaded by a management station:

      OIDPrefix        MaxLatency  Description               StorageType
      ifEntry          100 mS      interfaces - builtin      readOnly
      0.0              100 mS      system element - builtin  readOnly
      frCircuitEntry   100 mS      FR Circuits - builtin     readOnly
      hrSWRunEntry     60 sec      Running Processes         volatile

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            Note that agents may automatically configure elements in this
            table for frequently used element types (interfaces, circuits,
            etc.).  In particular, it may configure elements for whom
            discovery is optimized in one or both of the following ways:

            1. The agent may discover elements by scanning internal data
               structures as opposed to issuing local SNMP requests.  It is
               possible to recreate the exact semantics described in this
               table even if local SNMP requests are not issued.

            2. The agent may receive asynchronous notification of new
               elements (for example, 'card inserted') and use that
               information to instantly create elements rather than
               through polling.  A similar feature might be available for
               the deletion of elements.

            Note that the disposition of agent-installed entries is
            described by the pmPolicyStorageType object."
        ::= { pmMib 3 }

    pmElementTypeRegEntry OBJECT-TYPE
        SYNTAX      PmElementTypeRegEntry
        MAX-ACCESS  not-accessible
        STATUS      current
        DESCRIPTION
            "A registration of an element type.

            Note that some values of this table's index may result in an
            instance name that exceeds a length of 128 sub-identifiers,
            which exceeds the maximum for the SNMP protocol.
            Implementations should take care to avoid such values."
        INDEX       { pmElementTypeRegOIDPrefix }
        ::= { pmElementTypeRegTable 1 }

    PmElementTypeRegEntry ::= SEQUENCE {
        pmElementTypeRegOIDPrefix     OBJECT IDENTIFIER,
        pmElementTypeRegMaxLatency    Unsigned32,
        pmElementTypeRegDescription   PmUTF8String,
        pmElementTypeRegStorageType   StorageType,
        pmElementTypeRegRowStatus     RowStatus
    }

    pmElementTypeRegOIDPrefix OBJECT-TYPE
        SYNTAX      OBJECT IDENTIFIER
        MAX-ACCESS  not-accessible
        STATUS      current
        DESCRIPTION
            "This OBJECT IDENTIFIER value identifies a table in which all

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            elements of this type will be found.  Every row in the
            referenced table will be treated as an element for the
            period of time that it remains in the table.  The agent will
            then execute policy conditions and actions as appropriate on
            each of these elements.

            This object identifier value is specified down to the 'entry'
            component (e.g., ifEntry) of the identifier.

            The index of each discovered row will be passed to each
            invocation of the policy condition and policy action.

            The actual mechanism by which instances are discovered is
            implementation dependent.  Periodic walks of the table to
            discover the rows in the table is one such mechanism.  This
            mechanism has the advantage that it can be performed by an
            agent with no knowledge of the names, syntax, or semantics
            of the MIB objects in the table.  This mechanism also serves as
            the reference design.  Other implementation-dependent
            mechanisms may be implemented that are more efficient (perhaps
            because they are hard coded) or that don't require polling.
            These mechanisms must discover the same elements as would the
            table-walking reference design.

            This object can contain a OBJECT IDENTIFIER, '0.0'.
            '0.0' represents the single instance of the system
            itself and provides an execution context for policies to
            operate on the 'system element' and on MIB objects
            modeled as scalars.  For example, '0.0' gives an execution
            context for policy-based selection of the operating system
            code version (likely modeled as a scalar MIB object).  The
            element type '0.0' always exists; as a consequence, no actual
            discovery will take place, and the pmElementTypeRegMaxLatency
            object will have no effect for the '0.0' element
            type.  However, if the '0.0' element type is not registered in
            the table, policies will not be executed on the '0.0' element.

            When a policy is invoked on behalf of a '0.0' entry in this
            table, the element name will be '0.0', and there is no index
            of 'this element' (in other words, it has zero length).

            As this object is used in the index for the
            pmElementTypeRegTable, users of this table should be careful
            not to create entries that would result in instance names with
            more than 128 sub-identifiers."
        ::= { pmElementTypeRegEntry 2 }

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    pmElementTypeRegMaxLatency OBJECT-TYPE
        SYNTAX      Unsigned32
        UNITS       "milliseconds"
        MAX-ACCESS  read-create
        STATUS      current
        DESCRIPTION
            "The PM agent is responsible for discovering new elements of
            types that are registered.  This object lets the manager
            control the maximum amount of time that may pass between the
            time an element is created and when it is discovered.

            In other words, in any given interval of this duration, all
            new elements must be discovered.  Note that how the policy
            agent schedules the checking of various elements within this
            interval is an implementation-dependent matter."
        ::= { pmElementTypeRegEntry 3 }

    pmElementTypeRegDescription OBJECT-TYPE
        SYNTAX      PmUTF8String (SIZE (0..64))
        MAX-ACCESS  read-create
        STATUS      current
        DESCRIPTION
            "A descriptive label for this registered type."
        ::= { pmElementTypeRegEntry 4 }

    pmElementTypeRegStorageType OBJECT-TYPE
        SYNTAX      StorageType
        MAX-ACCESS  read-create
        STATUS      current
        DESCRIPTION
            "This object defines whether this row is kept
             in volatile storage and lost upon reboot or
             backed up by non-volatile or permanent storage.

             If the value of this object is 'permanent', no values in the
             associated row have to be writable."
        ::= { pmElementTypeRegEntry 5 }

    pmElementTypeRegRowStatus OBJECT-TYPE
        SYNTAX      RowStatus
        MAX-ACCESS  read-create
        STATUS      current
        DESCRIPTION
            "The status of this registration entry.

            If the value of this object is active, no objects in this row
            may be modified."
        ::= { pmElementTypeRegEntry 6 }

    Waldbusser, et al.          Standards Track                    [Page 88]

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    -- Role Table

    pmRoleTable OBJECT-TYPE
        SYNTAX      SEQUENCE OF PmRoleEntry
        MAX-ACCESS  not-accessible
        STATUS      current
        DESCRIPTION
            "The pmRoleTable is a read-create table that organizes role
            strings sorted by element.  This table is used to create and
            modify role strings and their associations, as well as to allow
            a management station to learn about the existence of roles and
            their associations.

            It is the responsibility of the agent to keep track of any
            re-indexing of the underlying SNMP elements and to continue to
            associate role strings with the element with which they were
            initially configured.

            Policy MIB agents that have elements in multiple local SNMP
            contexts have to allow some roles to be assigned to elements
            in particular contexts.  This is particularly true when some
            elements have the same names in different contexts and the
            context is required to disambiguate them.  In those situations,
            a value for the pmRoleContextName may be provided.  When a
            pmRoleContextName value is not provided, the assignment is to
            the element in the default context.

            Policy MIB agents that discover elements on other systems and
            execute policies on their behalf need to have access to role
            information for these remote elements.  In such situations,
            role assignments for other systems can be stored in this table
            by providing values for the pmRoleContextEngineID parameters.

        For example:
        Example:
        element       role    context ctxEngineID   #comment
        ifindex.1     gold                          local, default context
        ifindex.2     gold                          local, default context
        repeaterid.1  foo     rptr1                 local, rptr1 context
        repeaterid.1  bar     rptr2                 local, rptr2 context
        ifindex.1     gold    ''      A             different system
        ifindex.1     gold    ''      B             different system

             The agent must store role string associations in non-volatile
             storage."
        ::= { pmMib 4 }

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    pmRoleEntry OBJECT-TYPE
        SYNTAX      PmRoleEntry
        MAX-ACCESS  not-accessible
        STATUS      current
        DESCRIPTION
             "A role string entry associates a role string with an
             individual element.

             Note that some combinations of index values may result in an
             instance name that exceeds a length of 128 sub-identifiers,
             which exceeds the maximum for the SNMP
             protocol.  Implementations should take care to avoid such
             combinations."
        INDEX       { pmRoleElement, pmRoleContextName,
                      pmRoleContextEngineID, pmRoleString }
        ::= { pmRoleTable 1 }

    PmRoleEntry ::= SEQUENCE {
        pmRoleElement          RowPointer,
        pmRoleContextName      SnmpAdminString,
        pmRoleContextEngineID  OCTET STRING,
        pmRoleString           PmUTF8String,
        pmRoleStatus           RowStatus
    }

    pmRoleElement OBJECT-TYPE
        SYNTAX      RowPointer
        MAX-ACCESS  not-accessible
        STATUS      current
        DESCRIPTION
             "The element with which this role string is associated.

             For example, if the element is interface 3, then this object
             will contain the OID for 'ifIndex.3'.

             If the agent assigns new indexes in the MIB table to
             represent the same underlying element (re-indexing), the
             agent will modify this value to contain the new index for the
             underlying element.

             As this object is used in the index for the pmRoleTable,
             users of this table should be careful not to create entries
             that would result in instance names with more than 128
             sub-identifiers."
        ::= { pmRoleEntry 1 }

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    pmRoleContextName OBJECT-TYPE
        SYNTAX      SnmpAdminString (SIZE (0..32))
        MAX-ACCESS  not-accessible
        STATUS      current
        DESCRIPTION
            "If the associated element is not in the default SNMP context
            for the target system, this object is used to identify the
            context.  If the element is in the default context, this object
            is equal to the empty string."
        ::= { pmRoleEntry 2 }

    pmRoleContextEngineID OBJECT-TYPE
        SYNTAX      OCTET STRING (SIZE (0 | 5..32))
        MAX-ACCESS  not-accessible
        STATUS      current
        DESCRIPTION
            "If the associated element is on a remote system, this object
            is used to identify the remote system.  This object contains
            the contextEngineID of the system for which this role string
            assignment is valid.  If the element is on the local system
            this object will be the empty string."
        ::= { pmRoleEntry 3 }

    pmRoleString OBJECT-TYPE
        SYNTAX      PmUTF8String (SIZE (0..64))
        MAX-ACCESS  not-accessible
        STATUS      current
        DESCRIPTION
             "The role string that is associated with an element through
             this table.  All role strings must have been successfully
             transformed by Stringprep RFC 3454.  Management stations
             must perform this translation and must only set this object
             to string values that have been transformed.

             A role string is an administratively specified characteristic
             of a managed element (for example, an interface).  It is a
             selector for policy rules, that determines the applicability of
             the rule to a particular managed element."
        ::= { pmRoleEntry 4 }

    pmRoleStatus OBJECT-TYPE
        SYNTAX      RowStatus
        MAX-ACCESS  read-create
        STATUS      current
        DESCRIPTION
             "The status of this role string.

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             If the value of this object is active, no object in this row
             may be modified."
        ::= { pmRoleEntry 5 }

    -- Capabilities table

    pmCapabilitiesTable OBJECT-TYPE
        SYNTAX      SEQUENCE OF PmCapabilitiesEntry
        MAX-ACCESS  not-accessible
        STATUS      current
        DESCRIPTION
             "The pmCapabilitiesTable contains a description of
             the inherent capabilities of the system so that
             management stations can learn of an agent's capabilities and
             differentially install policies based on the capabilities.

             Capabilities are expressed at the system level.  There can be
             variation in how capabilities are realized from one vendor or
             model to the next.  Management systems should consider these
             differences before selecting which policy to install in a
             system."
        ::= { pmMib 5 }

    pmCapabilitiesEntry OBJECT-TYPE
        SYNTAX      PmCapabilitiesEntry
        MAX-ACCESS  not-accessible
        STATUS      current
        DESCRIPTION
             "A capabilities entry holds an OID indicating support for a
             particular capability.  Capabilities may include hardware and
             software functions and the implementation of MIB
             Modules.  The semantics of the OID are defined in the
             description of pmCapabilitiesType.

             Entries appear in this table if any element in the system has
             a specific capability.  A capability should appear in this
             table only once, regardless of the number of elements in the
             system with that capability.  An entry is removed from this
             table when the last element in the system that has the
             capability is removed.  In some cases, capabilities are
             dynamic and exist only in software.  This table should have an
             entry for the capability even if there are no current
             instances.  Examples include systems with database or WEB
             services.  While the system has the ability to create new
             databases or WEB services, the entry should exist.  In these
             cases, the ability to create these services could come from
             other processes that are running in the system, even though
             there are no currently open databases or WEB servers running.

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             Capabilities may include the implementation of MIB Modules
             but need not be limited to those that represent MIB Modules
             with one or more configurable objects.  It may also be
             valuable to include entries for capabilities that do not
             include configuration objects, as that information, in
             combination with other entries in this table, might be used
             by the management software to determine whether to
             install a policy.

             Vendor software may also add entries in this table to express
             capabilities from their private branch.

             Note that some values of this table's index may result in an
             instance name that exceeds a length of 128 sub-identifiers,
             which exceeds the maximum for the SNMP
             protocol.  Implementations should take care to avoid such
             values."
        INDEX       { pmCapabilitiesType }
        ::= { pmCapabilitiesTable 1 }

    PmCapabilitiesEntry ::= SEQUENCE {
        pmCapabilitiesType               OBJECT IDENTIFIER
    }

    pmCapabilitiesType OBJECT-TYPE
        SYNTAX      OBJECT IDENTIFIER
        MAX-ACCESS  read-only
        STATUS      current
        DESCRIPTION
             "There are three types of OIDs that may be present in the
             pmCapabilitiesType object:

             1) The OID of a MODULE-COMPLIANCE macro that represents the
             highest level of compliance realized by the agent for that
             MIB Module.  For example, an agent that implements the OSPF
             MIB Module at the highest level of compliance would have the
             value of '1.3.6.1.2.1.14.15.2' in the pmCapabilitiesType
             object.  For software that realizes standard MIB
             Modules that do not have compliance statements, the base OID
             of the MIB Module should be used instead.  If the OSPF MIB
             Module had not been created with a compliance statement, then
             the correct value of the pmCapabilitiesType would be
             '1.3.6.1.2.1.14'.  In the cases where multiple compliance
             statements in a MIB Module are supported by the agent, and
             where one compliance statement does not by definition include
             the other, each of the compliance OIDs would have entries in
             this table.

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             MIB Documents can contain more than one MIB Module.  In the
             case of OSPF, there is a second MIB Module
             that describes notifications for the OSPF Version 2 Protocol.
             If the agent also realizes these functions, an entry will
             also exist for those capabilities in this table.

             2) Vendors should install OIDs in this table that represent
             vendor-specific capabilities.  These capabilities can be
             expressed just as those described above for MIB Modules on
             the standards track.  In addition, vendors may install any
             OID they desire from their registered branch.  The OIDs may be
             at any level of granularity, from the root of their entire
             branch to an instance of a single OID.  There is no
             restriction on the number of registrations they may make,
             though care should be taken to avoid unnecessary entries.

             3) OIDs that represent one capability or a collection of
             capabilities that could be any collection of MIB Objects or
             hardware or software functions may be created in working
             groups and registered in a MIB Module.  Other entities (e.g.,
             vendors) may also make registrations.  Software will register
             these standard capability OIDs, as well as vendor specific
             OIDs.

             If the OID for a known capability is not present in the
             table, then it should be assumed that the capability is not
             implemented.

             As this object is used in the index for the
             pmCapabilitiesTable, users of this table should be careful
             not to create entries that would result in instance names
             with more than 128 sub-identifiers."
        ::= { pmCapabilitiesEntry 1 }

    -- Capabilities override table

    pmCapabilitiesOverrideTable OBJECT-TYPE
        SYNTAX      SEQUENCE OF PmCapabilitiesOverrideEntry
        MAX-ACCESS  not-accessible
        STATUS      current
        DESCRIPTION
             "The pmCapabilitiesOverrideTable allows management stations
             to override pmCapabilitiesTable entries that have been
             registered by the agent.  This facility can be used to avoid
             situations in which managers in the network send policies to
             a system that has advertised a capability in the
             pmCapabilitiesTable but that should not be installed on this
             particular system.  One example could be newly deployed

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             equipment that is still in a trial state in a trial state or
             resources reserved for some other administrative reason.
             This table can also be used to override entries in the
             pmCapabilitiesTable through the use of the
             pmCapabilitiesOverrideState object.  Capabilities can also be
             declared available in this table that were not registered in
             the pmCapabilitiesTable.  A management application can make
             an entry in this table for any valid OID and declare the
             capability available by setting the
             pmCapabilitiesOverrideState for that row to valid(1)."
        ::= { pmMib 6 }

    pmCapabilitiesOverrideEntry OBJECT-TYPE
        SYNTAX      PmCapabilitiesOverrideEntry
        MAX-ACCESS  not-accessible
        STATUS      current
        DESCRIPTION
             "An entry in this table indicates whether a particular
             capability is valid or invalid.

             Note that some values of this table's index may result in an
             instance name that exceeds a length of 128 sub-identifiers,
             which exceeds the maximum for the SNMP
             protocol.  Implementations should take care to avoid such
             values."
        INDEX       { pmCapabilitiesOverrideType }
        ::= { pmCapabilitiesOverrideTable 1 }

    PmCapabilitiesOverrideEntry ::= SEQUENCE {
        pmCapabilitiesOverrideType               OBJECT IDENTIFIER,
        pmCapabilitiesOverrideState              INTEGER,
        pmCapabilitiesOverrideRowStatus          RowStatus
    }

    pmCapabilitiesOverrideType OBJECT-TYPE
        SYNTAX      OBJECT IDENTIFIER
        MAX-ACCESS  not-accessible
        STATUS      current
        DESCRIPTION
             "This is the OID of the capability that is declared valid or
             invalid by the pmCapabilitiesOverrideState value for this
             row.  Any valid OID, as described in the pmCapabilitiesTable,
             is permitted in the pmCapabilitiesOverrideType object.  This
             means that capabilities can be expressed at any level, from a
             specific instance of an object to a table or entire module.
             There are no restrictions on whether these objects are from
             standards track MIB documents or in the private branch of the
             MIB.

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             If an entry exists in this table for which there is a
             corresponding entry in the pmCapabilitiesTable, then this entry
             shall have precedence over the entry in the
             pmCapabilitiesTable.  All entries in this table must be
             preserved across reboots.

             As this object is used in the index for the
             pmCapabilitiesOverrideTable, users of this table should be
             careful not to create entries that would result in instance
             names with more than 128 sub-identifiers."
        ::= { pmCapabilitiesOverrideEntry 1 }

    pmCapabilitiesOverrideState OBJECT-TYPE
        SYNTAX      INTEGER {
                        invalid(1),
                        valid(2)
                    }
        MAX-ACCESS  read-create
        STATUS      current
        DESCRIPTION
             "A pmCapabilitiesOverrideState of invalid indicates that
             management software should not send policies to this system
             for the capability identified in the
             pmCapabilitiesOverrideType for this row of the table.  This
             behavior is the same whether the capability represented by
             the pmCapabilitiesOverrideType exists only in this table
             (that is, it was installed by an external management
             application) or exists in this table as well as the
             pmCapabilitiesTable.  This would be the case when a manager
             wanted to disable a capability that the native management
             system found and registered in the pmCapabilitiesTable.

             An entry in this table that has a pmCapabilitiesOverrideState
             of valid should be treated as though it appeared in the
             pmCapabilitiesTable.  If the entry also exists in the
             pmCapabilitiesTable in the pmCapabilitiesType object, and if
             the value of this object is valid, then the system shall
             operate as though this entry did not exist and policy
             installations and executions will continue in a normal
             fashion."
        ::= { pmCapabilitiesOverrideEntry 2 }

    pmCapabilitiesOverrideRowStatus OBJECT-TYPE
        SYNTAX      RowStatus
        MAX-ACCESS  read-create
        STATUS      current
        DESCRIPTION
             "The row status of this pmCapabilitiesOverrideEntry.

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             If the value of this object is active, no object in this row
             may be modified."
        ::= { pmCapabilitiesOverrideEntry 3 }

    -- The Schedule Group

    pmSchedLocalTime OBJECT-TYPE
        SYNTAX      DateAndTime (SIZE (11))
        MAX-ACCESS  read-only
        STATUS      current
        DESCRIPTION
            "The local time used by the scheduler.  Schedules that
             refer to calendar time will use the local time indicated
             by this object.  An implementation MUST return all 11 bytes
             of the DateAndTime textual-convention so that a manager
             may retrieve the offset from GMT time."
        ::= { pmMib 7 }

    --
    -- The schedule table that controls the scheduler.
    --

    pmSchedTable OBJECT-TYPE
        SYNTAX      SEQUENCE OF PmSchedEntry
        MAX-ACCESS  not-accessible
        STATUS      current
        DESCRIPTION
            "This table defines schedules for policies."
        ::= { pmMib 8 }

    pmSchedEntry OBJECT-TYPE
        SYNTAX      PmSchedEntry
        MAX-ACCESS  not-accessible
        STATUS      current
        DESCRIPTION
            "An entry describing a particular schedule.

            Unless noted otherwise, writable objects of this row can be
            modified independently of the current value of pmSchedRowStatus,
            pmSchedAdminStatus and pmSchedOperStatus.  In particular, it
            is legal to modify pmSchedWeekDay, pmSchedMonth, and
            pmSchedDay when pmSchedRowStatus is active."
        INDEX { pmSchedIndex }
        ::= { pmSchedTable 1 }

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    PmSchedEntry ::= SEQUENCE {
        pmSchedIndex          Unsigned32,
        pmSchedGroupIndex     Unsigned32,
        pmSchedDescr          PmUTF8String,
        pmSchedTimePeriod     PmUTF8String,
        pmSchedMonth          BITS,
        pmSchedDay            BITS,
        pmSchedWeekDay        BITS,
        pmSchedTimeOfDay      PmUTF8String,
        pmSchedLocalOrUtc     INTEGER,
        pmSchedStorageType    StorageType,
        pmSchedRowStatus      RowStatus
    }

    pmSchedIndex OBJECT-TYPE
        SYNTAX      Unsigned32 (1..4294967295)
        MAX-ACCESS  not-accessible
        STATUS      current
        DESCRIPTION
            "The locally unique, administratively assigned index for this
            scheduling entry."
        ::= { pmSchedEntry 1 }

    pmSchedGroupIndex OBJECT-TYPE
        SYNTAX      Unsigned32 (1..4294967295)
        MAX-ACCESS  read-create
        STATUS      current
        DESCRIPTION
            "The locally unique, administratively assigned index for the
            schedule group this scheduling entry belongs to.

            To assign multiple schedule entries to the same group, the
            pmSchedGroupIndex of each entry in the group will be set to
            the same value.  This pmSchedGroupIndex value must be equal to
            the pmSchedIndex of one of the entries in the group.  If the
            entry whose pmSchedIndex equals the pmSchedGroupIndex
            for the group is deleted, the agent will assign a new
            pmSchedGroupIndex to all remaining members of the group.

            If an entry is not a member of a group, its pmSchedGroupIndex
            must be assigned to the value of its pmSchedIndex.

            Policies that are controlled by a group of schedule entries
            are active when any schedule in the group is active."
        ::= { pmSchedEntry 2 }

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    pmSchedDescr OBJECT-TYPE
        SYNTAX      PmUTF8String
        MAX-ACCESS  read-create
        STATUS      current
        DESCRIPTION
            "The human-readable description of the purpose of this
            scheduling entry."
        DEFVAL { ''H }
        ::= { pmSchedEntry 3 }

    pmSchedTimePeriod OBJECT-TYPE
        SYNTAX      PmUTF8String (SIZE (0..31))
        MAX-ACCESS  read-create
        STATUS      current
        DESCRIPTION
            "The overall range of calendar dates and times over which this
            schedule is active.  It is stored in a slightly extended version
            of the format for a 'period-explicit' defined in RFC 2445.
            This format is expressed as a string representing the
            starting date and time, in which the character 'T' indicates
            the beginning of the time portion, followed by the solidus
            character, '/', followed by a similar string representing an
            end date and time.  The start of the period MUST be before the
            end of the period.  Date-Time values are expressed as
            substrings of the form 'yyyymmddThhmmss'.  For example:

                20000101T080000/20000131T130000

                  January 1, 2000, 0800 through January 31, 2000, 1PM

            The 'Date with UTC time' format defined in RFC 2445 in which
            the Date-Time string ends with the character 'Z' is not
            allowed.

            This 'period-explicit' format is also extended to allow two
            special cases in which one of the Date-Time strings is
            replaced with a special string defined in RFC 2445:

            1. If the first Date-Time value is replaced with the string
               'THISANDPRIOR', then the value indicates that the schedule
               is active at any time prior to the Date-Time that appears
               after the '/'.

            2. If the second Date-Time is replaced with the string
               'THISANDFUTURE', then the value indicates that the schedule
               is active at any time after the Date-Time that appears
               before the '/'.

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            Note that although RFC 2445 defines these two strings, they are
            not specified for use in the 'period-explicit' format.  The use
            of these strings represents an extension to the
            'period-explicit' format."
        ::= { pmSchedEntry 4 }

    pmSchedMonth OBJECT-TYPE
        SYNTAX      BITS {
                        january(0),
                        february(1),
                        march(2),
                        april(3),
                        may(4),
                        june(5),
                        july(6),
                        august(7),
                        september(8),
                        october(9),
                        november(10),
                        december(11)
                    }

        MAX-ACCESS  read-create
        STATUS      current
        DESCRIPTION
            "Within the overall time period specified in the
            pmSchedTimePeriod object, the value of this object specifies
            the specific months within that time period when the schedule
            is active.  Setting all bits will cause the schedule to act
            independently of the month."
        DEFVAL { { january, february, march, april, may, june, july,
                   august, september, october, november, december } }
        ::= { pmSchedEntry 5 }

    pmSchedDay OBJECT-TYPE
        SYNTAX      BITS {
                        d1(0),   d2(1),   d3(2),   d4(3),   d5(4),
                        d6(5),   d7(6),   d8(7),   d9(8),   d10(9),
                        d11(10), d12(11), d13(12), d14(13), d15(14),
                        d16(15), d17(16), d18(17), d19(18), d20(19),
                        d21(20), d22(21), d23(22), d24(23), d25(24),
                        d26(25), d27(26), d28(27), d29(28), d30(29),
                        d31(30),
                        r1(31),  r2(32),  r3(33),  r4(34),  r5(35),
                        r6(36),  r7(37),  r8(38),  r9(39),  r10(40),
                        r11(41), r12(42), r13(43), r14(44), r15(45),
                        r16(46), r17(47), r18(48), r19(49), r20(50),
                        r21(51), r22(52), r23(53), r24(54), r25(55),

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                        r26(56), r27(57), r28(58), r29(59), r30(60),
                        r31(61)
                    }
        MAX-ACCESS  read-create
        STATUS      current
        DESCRIPTION
            "Within the overall time period specified in the
            pmSchedTimePeriod object, the value of this object specifies
            the specific days of the month within that time period when
            the schedule is active.

            There are two sets of bits one can use to define the day
            within a month:

            Enumerations starting with the letter 'd' indicate a
            day in a month relative to the first day of a month.
            The first day of the month can therefore be specified
            by setting the bit d1(0), and d31(30) means the last
            day of a month with 31 days.

            Enumerations starting with the letter 'r' indicate a
            day in a month in reverse order, relative to the last
            day of a month.  The last day in the month can therefore
            be specified by setting the bit r1(31), and r31(61) means
            the first day of a month with 31 days.

            Setting multiple bits will include several days in the set
            of possible days for this schedule.  Setting all bits starting
            with the letter 'd' or all bits starting with the letter 'r'
            will cause the schedule to act independently of the day of the
            month."
        DEFVAL { {  d1, d2, d3, d4, d5, d6, d7, d8, d9, d10,
                    d11, d12, d13, d14, d15, d16, d17, d18, d19, d20,
                    d21, d22, d23, d24, d25, d26, d27, d28, d29, d30,
                    d31, r1, r2, r3, r4, r5, r6, r7, r8, r9, r10,
                    r11, r12, r13, r14, r15, r16, r17, r18, r19, r20,
                    r21, r22, r23, r24, r25, r26, r27, r28, r29, r30,
                    r31 } }
        ::= { pmSchedEntry 6 }

    pmSchedWeekDay OBJECT-TYPE
        SYNTAX      BITS {
                        sunday(0),
                        monday(1),
                        tuesday(2),
                        wednesday(3),
                        thursday(4),
                        friday(5),

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                        saturday(6)
                    }
        MAX-ACCESS  read-create
        STATUS      current
        DESCRIPTION
            "Within the overall time period specified in the
            pmSchedTimePeriod object, the value of this object specifies
            the specific days of the week within that time period when
            the schedule is active.  Setting all bits will cause the
            schedule to act independently of the day of the week."
        DEFVAL { { sunday, monday, tuesday, wednesday, thursday,
                   friday, saturday } }
        ::= { pmSchedEntry 7 }

    pmSchedTimeOfDay OBJECT-TYPE
        SYNTAX      PmUTF8String (SIZE (0..15))
        MAX-ACCESS  read-create
        STATUS      current
        DESCRIPTION

            "Within the overall time period specified in the
            pmSchedTimePeriod object, the value of this object specifies
            the range of times in a day when the schedule is active.

            This value is stored in a format based on the RFC 2445 format
            for 'time': The character 'T' followed by a 'time' string,
            followed by the solidus character, '/', followed by the
            character 'T', followed by a second time string.  The first time
            indicates the beginning of the range, and the second time
            indicates the end.  Thus, this value takes the following
            form:

                'Thhmmss/Thhmmss'.

            The second substring always identifies a later time than the
            first substring.  To allow for ranges that span midnight,
            however, the value of the second string may be smaller than
            the value of the first substring.  Thus, 'T080000/T210000'
            identifies the range from 0800 until 2100, whereas
            'T210000/T080000' identifies the range from 2100 until 0800 of
            the following day.

            When a range spans midnight, by definition it includes parts
            of two successive days.  When one of these days is also
            selected by either the MonthOfYearMask, DayOfMonthMask, and/or
            DayOfWeekMask, but the other day is not, then the policy is
            active only during the portion of the range that falls on the
            selected day.  For example, if the range extends from 2100

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            until 0800, and the day of week mask selects Monday and
            Tuesday, then the policy is active during the following three
            intervals:

                From midnight Sunday until 0800 Monday
                From 2100 Monday until 0800 Tuesday
                From 2100 Tuesday until 23:59:59 Tuesday

             Setting this value to 'T000000/T235959' will cause the
             schedule to act independently of the time of day."
        DEFVAL { '543030303030302F54323335393539'H } -- T000000/T235959
        ::= { pmSchedEntry 8 }

    pmSchedLocalOrUtc OBJECT-TYPE
        SYNTAX      INTEGER {
                        localTime(1),
                        utcTime(2)
                    }
        MAX-ACCESS  read-create
        STATUS      current
        DESCRIPTION
            "This object indicates whether the times represented in the
            TimePeriod object and in the various Mask objects represent
            local times or UTC times."
        DEFVAL { utcTime }
        ::= { pmSchedEntry 9 }

    pmSchedStorageType OBJECT-TYPE
        SYNTAX      StorageType
        MAX-ACCESS  read-create
        STATUS      current
        DESCRIPTION
            "This object defines whether this schedule entry is kept
             in volatile storage and lost upon reboot or
             backed up by non-volatile or permanent storage.

             Conceptual rows having the value 'permanent' must allow write
             access to the columnar objects pmSchedDescr, pmSchedWeekDay,
             pmSchedMonth, and pmSchedDay.

             If the value of this object is 'permanent', no values in the
             associated row have to be writable."
        DEFVAL { volatile }
        ::= { pmSchedEntry 10 }

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    pmSchedRowStatus OBJECT-TYPE
        SYNTAX      RowStatus
        MAX-ACCESS  read-create
        STATUS      current
        DESCRIPTION
            "The status of this schedule entry.

             If the value of this object is active, no object in this row
             may be modified."
        ::= { pmSchedEntry 11 }

    -- Policy Tracking

    -- The "policy to element" (PE) table and the "element to policy" (EP)
    -- table track the status of execution contexts grouped by policy and
    -- element respectively.

    pmTrackingPETable OBJECT-TYPE
        SYNTAX      SEQUENCE OF PmTrackingPEEntry
        MAX-ACCESS  not-accessible
        STATUS      current
        DESCRIPTION
             "The pmTrackingPETable describes what elements
             are active (under control of) a policy.  This table is indexed
             in order to optimize retrieval of the entire status for a
             given policy."
        ::= { pmMib 9 }

    pmTrackingPEEntry OBJECT-TYPE
        SYNTAX      PmTrackingPEEntry
        MAX-ACCESS  not-accessible
        STATUS      current
        DESCRIPTION
             "An entry in the pmTrackingPETable.  The pmPolicyIndex in
             the index specifies the policy tracked by this entry.

             Note that some combinations of index values may result in an
             instance name that exceeds a length of 128 sub-identifiers,
             which exceeds the maximum for the SNMP
             protocol.  Implementations should take care to avoid such
             combinations."
        INDEX       { pmPolicyIndex, pmTrackingPEElement,
                      pmTrackingPEContextName, pmTrackingPEContextEngineID }
        ::= { pmTrackingPETable 1 }

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    PmTrackingPEEntry ::= SEQUENCE {
        pmTrackingPEElement          RowPointer,
        pmTrackingPEContextName      SnmpAdminString,
        pmTrackingPEContextEngineID  OCTET STRING,
        pmTrackingPEInfo             BITS
    }

    pmTrackingPEElement OBJECT-TYPE
        SYNTAX      RowPointer
        MAX-ACCESS  not-accessible
        STATUS      current
        DESCRIPTION
             "The element that is acted upon by the associated policy.

             As this object is used in the index for the
             pmTrackingPETable, users of this table should be careful not
             to create entries that would result in instance names with
             more than 128 sub-identifiers."
        ::= { pmTrackingPEEntry 1 }

    pmTrackingPEContextName OBJECT-TYPE
        SYNTAX      SnmpAdminString (SIZE (0..32))
        MAX-ACCESS  not-accessible
        STATUS      current
        DESCRIPTION
            "If the associated element is not in the default SNMP context
            for the target system, this object is used to identify the
            context.  If the element is in the default context, this object
            is equal to the empty string."
        ::= { pmTrackingPEEntry 2 }

    pmTrackingPEContextEngineID OBJECT-TYPE
        SYNTAX      OCTET STRING (SIZE (0 | 5..32))
        MAX-ACCESS  not-accessible
        STATUS      current
        DESCRIPTION
            "If the associated element is on a remote system, this object
            is used to identify the remote system.  This object contains
            the contextEngineID of the system on which the associated
            element resides.  If the element is on the local system,
            this object will be the empty string."
        ::= { pmTrackingPEEntry 3 }

    pmTrackingPEInfo OBJECT-TYPE
        SYNTAX      BITS {
                        actionSkippedDueToPrecedence(0),
                        conditionRunTimeException(1),
                        conditionUserSignal(2),

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                        actionRunTimeException(3),
                        actionUserSignal(4)
                    }
        MAX-ACCESS  read-only
        STATUS      current
        DESCRIPTION
             "This object returns information about the previous policy
             script executions.

             If the actionSkippedDueToPrecedence(1) bit is set, the last
             execution of the associated policy condition returned non-zero,
             but the action is not active, because it was trumped by a
             matching policy condition in the same precedence group with a
             higher precedence value.

             If the conditionRunTimeException(2) bit is set, the last
             execution of the associated policy condition encountered a
             run-time exception and aborted.

             If the conditionUserSignal(3) bit is set, the last
             execution of the associated policy condition called the
             signalError() function.

             If the actionRunTimeException(4) bit is set, the last
             execution of the associated policy action encountered a
             run-time exception and aborted.

             If the actionUserSignal(5) bit is set, the last
             execution of the associated policy action called the
             signalError() function.

             Entries will only exist in this table of one or more bits are
             set.  In particular, if an entry does not exist for a
             particular policy/element combination, it can be assumed that
             the policy's condition did not match 'this element'."
        ::= { pmTrackingPEEntry 4 }

    -- Element to Policy Table

    pmTrackingEPTable OBJECT-TYPE
        SYNTAX      SEQUENCE OF PmTrackingEPEntry
        MAX-ACCESS  not-accessible
        STATUS      current
        DESCRIPTION
             "The pmTrackingEPTable describes what policies
             are controlling an element.  This table is indexed in
             order to optimize retrieval of the status of all policies
             active for a given element."

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        ::= { pmMib 10 }

    pmTrackingEPEntry OBJECT-TYPE
        SYNTAX      PmTrackingEPEntry
        MAX-ACCESS  not-accessible
        STATUS      current
        DESCRIPTION
             "An entry in the pmTrackingEPTable.  Entries exist for all
             element/policy combinations for which the policy's condition
             matches and only if the schedule for the policy is active.

             The pmPolicyIndex in the index specifies the policy
             tracked by this entry.

             Note that some combinations of index values may result in an
             instance name that exceeds a length of 128 sub-identifiers,
             which exceeds the maximum for the SNMP protocol.
             Implementations should take care to avoid such combinations."
        INDEX       { pmTrackingEPElement, pmTrackingEPContextName,
                      pmTrackingEPContextEngineID, pmPolicyIndex }
        ::= { pmTrackingEPTable 1 }

    PmTrackingEPEntry ::= SEQUENCE {
        pmTrackingEPElement          RowPointer,
        pmTrackingEPContextName      SnmpAdminString,
        pmTrackingEPContextEngineID  OCTET STRING,
        pmTrackingEPStatus           INTEGER
    }

    pmTrackingEPElement OBJECT-TYPE
        SYNTAX      RowPointer
        MAX-ACCESS  not-accessible
        STATUS      current
        DESCRIPTION
             "The element acted upon by the associated policy.

             As this object is used in the index for the
             pmTrackingEPTable, users of this table should be careful
             not to create entries that would result in instance names
             with more than 128 sub-identifiers."
        ::= { pmTrackingEPEntry 1 }

    pmTrackingEPContextName OBJECT-TYPE
        SYNTAX      SnmpAdminString (SIZE (0..32))
        MAX-ACCESS  not-accessible
        STATUS      current
        DESCRIPTION
            "If the associated element is not in the default SNMP context

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            for the target system, this object is used to identify the
            context.  If the element is in the default context, this object
            is equal to the empty string."
        ::= { pmTrackingEPEntry 2 }

    pmTrackingEPContextEngineID OBJECT-TYPE
        SYNTAX      OCTET STRING (SIZE (0 | 5..32))
        MAX-ACCESS  not-accessible
        STATUS      current
        DESCRIPTION
            "If the associated element is on a remote system, this object
            is used to identify the remote system.  This object contains
            the contextEngineID of the system on which the associated
            element resides.  If the element is on the local system,
            this object will be the empty string."
        ::= { pmTrackingEPEntry 3 }

    pmTrackingEPStatus OBJECT-TYPE
        SYNTAX      INTEGER {
                        on(1),
                        forceOff(2)
                    }
        MAX-ACCESS  read-write
        STATUS      current
        DESCRIPTION
             "This entry will only exist if the calendar for the policy is
             active and if the associated policyCondition returned 1 for
             'this element'.

             A policy can be forcibly disabled on a particular element
             by setting this value to forceOff(2).  The agent should then
             act as though the policyCondition failed for 'this element'.
             The forceOff(2) state will persist (even across reboots) until
             this value is set to on(1) by a management request.  The
             forceOff(2) state may be set even if the entry does not
             previously exist so that future policy invocations can be
             avoided.

             Unless forcibly disabled, if this entry exists, its value
             will be on(1)."
        ::= { pmTrackingEPEntry 4 }

    -- Policy Debugging Table

    pmDebuggingTable OBJECT-TYPE
        SYNTAX      SEQUENCE OF PmDebuggingEntry
        MAX-ACCESS  not-accessible
        STATUS      current

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        DESCRIPTION
             "Policies that have debugging turned on will generate a log
             entry in the policy debugging table for every runtime
             exception that occurs in either the condition or action
             code.

             The pmDebuggingTable logs debugging messages when
             policies experience run-time exceptions in either the condition
             or action code and the associated pmPolicyDebugging object
             has been turned on.

             The maximum number of debugging entries that will be stored
             and the maximum length of time an entry will be kept are an
             implementation-dependent manner.  If entries must
             be discarded to make room for new entries, the oldest entries
             must be discarded first.

             If the system restarts, all debugging entries may be deleted."
        ::= { pmMib 11 }

    pmDebuggingEntry OBJECT-TYPE
        SYNTAX      PmDebuggingEntry
        MAX-ACCESS  not-accessible
        STATUS      current
        DESCRIPTION
             "An entry in the pmDebuggingTable.  The pmPolicyIndex in the
             index specifies the policy that encountered the exception
             that led to this log entry.

             Note that some combinations of index values may result in an
             instance name that exceeds a length of 128 sub-identifiers,
             which exceeds the maximum for the SNMP protocol.
             Implementations should take care to avoid such combinations."
        INDEX       { pmPolicyIndex, pmDebuggingElement,
                      pmDebuggingContextName, pmDebuggingContextEngineID,
                      pmDebuggingLogIndex }
        ::= { pmDebuggingTable 1 }

    PmDebuggingEntry ::= SEQUENCE {
        pmDebuggingElement          RowPointer,
        pmDebuggingContextName      SnmpAdminString,
        pmDebuggingContextEngineID  OCTET STRING,
        pmDebuggingLogIndex         Unsigned32,
        pmDebuggingMessage          PmUTF8String
    }

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    pmDebuggingElement OBJECT-TYPE
        SYNTAX      RowPointer
        MAX-ACCESS  not-accessible
        STATUS      current
        DESCRIPTION
             "The element the policy was executing on when it encountered
             the error that led to this log entry.

             For example, if the element is interface 3, then this object
             will contain the OID for 'ifIndex.3'.

             As this object is used in the index for the
             pmDebuggingTable, users of this table should be careful
             not to create entries that would result in instance names
             with more than 128 sub-identifiers."
        ::= { pmDebuggingEntry 1 }

    pmDebuggingContextName OBJECT-TYPE
        SYNTAX      SnmpAdminString (SIZE (0..32))
        MAX-ACCESS  not-accessible
        STATUS      current
        DESCRIPTION
            "If the associated element is not in the default SNMP context
            for the target system, this object is used to identify the
            context.  If the element is in the default context, this object
            is equal to the empty string."
        ::= { pmDebuggingEntry 2 }

    pmDebuggingContextEngineID OBJECT-TYPE
        SYNTAX      OCTET STRING (SIZE (0 | 5..32))
        MAX-ACCESS  not-accessible
        STATUS      current
        DESCRIPTION
            "If the associated element is on a remote system, this object
            is used to identify the remote system.  This object contains
            the contextEngineID of the system on which the associated
            element resides.  If the element is on the local system,
            this object will be the empty string."
        ::= { pmDebuggingEntry 3 }

    pmDebuggingLogIndex OBJECT-TYPE
        SYNTAX      Unsigned32 (1..4294967295)
        MAX-ACCESS  not-accessible
        STATUS      current
        DESCRIPTION
             "A unique index for this log entry among other log entries
             for this policy/element combination."
        ::= { pmDebuggingEntry 4 }

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    pmDebuggingMessage OBJECT-TYPE
        SYNTAX      PmUTF8String (SIZE (0..128))
        MAX-ACCESS  read-only
        STATUS      current
        DESCRIPTION
             "An error message generated by the policy execution
             environment.  It is recommended that this message include the
             time of day when the message was generated, if known."
        ::= { pmDebuggingEntry 5 }

    -- Notifications

    pmNotifications OBJECT IDENTIFIER ::= { pmMib 0 }

    pmNewRoleNotification NOTIFICATION-TYPE
        OBJECTS     { pmRoleStatus }
        STATUS      current
        DESCRIPTION
            "The pmNewRoleNotification is sent when an agent is configured
            with its first instance of a previously unused role string
            (not every time a new element is given a particular role).

            An instance of the pmRoleStatus object is sent containing
            the new roleString in its index.  In the event that two or
            more elements are given the same role simultaneously, it is an
            implementation-dependent matter as to which pmRoleTable
            instance will be included in the notification."
        ::= { pmNotifications 1 }

    pmNewCapabilityNotification NOTIFICATION-TYPE
        OBJECTS     { pmCapabilitiesType }
        STATUS      current
        DESCRIPTION
            "The pmNewCapabilityNotification is sent when an agent
            gains a new capability that did not previously exist in any
            element on the system (not every time an element gains a
            particular capability).

            An instance of the pmCapabilitiesType object is sent containing
            the identity of the new capability.  In the event that two or
            more elements gain the same capability simultaneously, it is an
            implementation-dependent matter as to which pmCapabilitiesType
            instance will be included in the notification."
        ::= { pmNotifications 2 }

    pmAbnormalTermNotification NOTIFICATION-TYPE
        OBJECTS     { pmTrackingPEInfo }
        STATUS      current

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        DESCRIPTION
            "The pmAbnormalTermNotification is sent when a policy's
            pmPolicyAbnormalTerminations gauge value changes from zero to
            any value greater than zero and no such notification has been
            sent for that policy in the last 5 minutes.

            The notification contains an instance of the pmTrackingPEInfo
            object where the pmPolicyIndex component of the index
            identifies the associated policy and the rest of the index
            identifies an element on which the policy failed."
        ::= { pmNotifications 3 }

    -- Compliance Statements

        pmConformance   OBJECT IDENTIFIER ::= { pmMib 12 }
        pmCompliances   OBJECT IDENTIFIER ::= { pmConformance 1 }
        pmGroups        OBJECT IDENTIFIER ::= { pmConformance 2 }

    pmCompliance MODULE-COMPLIANCE
        STATUS  current
        DESCRIPTION
            "Describes the requirements for conformance to
            the Policy-Based Management MIB"
        MODULE  -- this module
            MANDATORY-GROUPS { pmPolicyManagementGroup, pmSchedGroup,
                               pmNotificationGroup }
        ::= { pmCompliances 1 }

    pmPolicyManagementGroup OBJECT-GROUP
        OBJECTS { pmPolicyPrecedenceGroup, pmPolicyPrecedence,
                  pmPolicySchedule, pmPolicyElementTypeFilter,
                  pmPolicyConditionScriptIndex, pmPolicyActionScriptIndex,
                  pmPolicyParameters,
                  pmPolicyConditionMaxLatency, pmPolicyActionMaxLatency,
                  pmPolicyMaxIterations,
                  pmPolicyDescription, pmPolicyMatches,
                  pmPolicyAbnormalTerminations,
                  pmPolicyExecutionErrors, pmPolicyDebugging,
                  pmPolicyStorageType, pmPolicyAdminStatus,
                  pmPolicyRowStatus, pmPolicyCodeText, pmPolicyCodeStatus,
                  pmElementTypeRegMaxLatency, pmElementTypeRegDescription,
                  pmElementTypeRegStorageType, pmElementTypeRegRowStatus,
                  pmRoleStatus,
                  pmCapabilitiesType, pmCapabilitiesOverrideState,
                  pmCapabilitiesOverrideRowStatus,
                  pmTrackingPEInfo,
                  pmTrackingEPStatus,
                  pmDebuggingMessage }

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        STATUS  current
        DESCRIPTION
            "Objects that allow for the creation and management of
            configuration policies."
        ::=  { pmGroups 1 }

    pmSchedGroup OBJECT-GROUP
        OBJECTS { pmSchedLocalTime, pmSchedGroupIndex,
                  pmSchedDescr, pmSchedTimePeriod,
                  pmSchedMonth, pmSchedDay, pmSchedWeekDay,
                  pmSchedTimeOfDay, pmSchedLocalOrUtc, pmSchedStorageType,
                  pmSchedRowStatus
                }
        STATUS current
        DESCRIPTION
            "Objects that allow for the scheduling of policies."
        ::= { pmGroups 2 }

    pmNotificationGroup NOTIFICATION-GROUP
        NOTIFICATIONS { pmNewRoleNotification,
                        pmNewCapabilityNotification,
                        pmAbnormalTermNotification }
        STATUS        current
        DESCRIPTION
            "Notifications sent by an Policy MIB agent."
        ::= { pmGroups 3 }

    pmBaseFunctionLibrary OBJECT IDENTIFIER ::= { pmGroups 4 }

    END

    12.  Relationship to Other MIB Modules

       When policy-based management is used specifically for (policy-based)
       configuration, the "Configuring Networks and Devices With SNMP" RFC
       3512 [19] document describes configuration management practices,
       terminology, and an example of a MIB Module that may be helpful to
       those developing and using this technology.

       The Policy MIB accesses system instrumentation for the purposes of
       policy evaluation, control, notification, monitoring, and error
       reporting.  This information is available to managers in the form of
       MIB objects.  Information about system configuration is modified by
       the Policy MIB through MIB objects defined in other MIB Modules.

       Details about the operational or configuration details of a system
       are retrieved by the manager via access to the specific MIB objects
       available in a network element.  As such, the Policy MIB can use any

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       standard or vendor-defined object that exists on a managed system.
       In particular, the Policy MIB may access standard or vendor specific
       objects that are instance-specific such as BGP timeout parameters and
       specific interface counters.

    13.  Security Considerations

       This MIB contains no objects for which read access would disclose
       sensitive information.

       There are a number of management objects defined in this MIB that
       have a MAX-ACCESS clause of read-write and/or read-create.  Such
       objects may be considered sensitive or vulnerable in some network
       environments.  The support for SET operations in a non-secure
       environment without proper protection can have a negative effect on
       network operations.

       With the exception of pmPolicyDescription, pmPolicyDebugging,
       pmElementTypeRegDescription, and pmSchedDescr, EVERY read-create and
       read-write object in this MIB should be considered sensitive because
       if an unauthorized user could manipulate these objects, s/he could
       cause the Policy MIB system to use the stored credentials of an
       authorized user to perform unauthorized and potentially harmful
       operations.

       There are no read-only objects in this MIB that contain sensitive
       information.

       SNMP versions prior to SNMPv3 did not include adequate security.
       Even if the network itself is secure (for example by using IPSec),
       even then, there is no control as to who on the secure network is
       allowed to access and GET/SET (read/change/create/delete) the objects
       in this MIB module.

       It is RECOMMENDED that implementers consider the security features as
       provided by the SNMPv3 framework (see [16], section 8), including
       full support for the SNMPv3 cryptographic mechanisms (for
       authentication and privacy).

       Further, deployment of SNMP versions prior to SNMPv3 is NOT
       RECOMMENDED.  Instead, it is RECOMMENDED to deploy SNMPv3 and to
       enable cryptographic security.  It is then a customer/operator
       responsibility to ensure that the SNMP entity giving access to an
       instance of this MIB module is properly configured to give access to
       the objects only to those principals (users) that have legitimate
       rights to indeed GET or SET (change/create/delete) them.

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       An implementation must ensure that access control rules are applied
       when SNMP operations are performed in policy scripts.  To ensure
       this, an implementation must record and maintain the security
       credentials of the last entity to modify each policy's
       pmPolicyAdminStatus object.  The credentials to store are the
       securityModel, securityName, and securityLevel and will be used as
       input parameters for isAccessAllowed from the Architecture for
       Describing SNMP Management Frameworks [1].  This mechanism was first
       introduced in the DISMAN-SCHEDULE-MIB [12].

       SNMP requests made when secModel, secName, and secLevel are specified
       use credentials stored in the local configuration datastore.  Access
       to these credentials depends on the security credentials of the last
       entity to modify the policy's pmPolicyAdminStatus object.  To
       determine whether the credentials can be accessed, the
       isAccessAllowed abstract service interface defined in RFC 3411 [1] is
       called:

          statusInformation =          -- success or errorIndication
            isAccessAllowed(

            IN   securityModel         -- Security Model used
            IN   securityName          -- principal who wants to access
            IN   securityLevel         -- Level of Security used
            IN   viewType              -- write
            IN   contextName           -- context containing variableName
            IN   variableName          -- OID for an object in the proper
                                       -- LCD entry
                 )

          The securityModel, securityName, and securityLevel parameters are
          set to the values that were recorded when the policy was modified.
          The viewType is set to write, and the contextName and variableName
          are set to select any read-create object in the appropriate LCD
          entry.

       Proper configuration of VACM requires that write access to an LCD
       entry not be given to entities that aren't authorized to use the
       credentials therein.

       Access control for SNMP requests made to the local system where
       secModel, secName, and secLevel aren't specified depends on the
       security credentials of the last entity to modify the policy's
       pmPolicyAdminStatus object.  To determine whether the operation
       should succeed, the isAccessAllowed abstract service interface
       defined in RFC 3411 [1] is called:

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    RFC 4011              Policy Based Management MIB             March 2005

          statusInformation =          -- success or errorIndication
            isAccessAllowed(
            IN   securityModel         -- Security Model in use
            IN   securityName          -- principal who wants to access
            IN   securityLevel         -- Level of Security
            IN   viewType              -- read, write, or notify view
            IN   contextName           -- context as specified
            IN   variableName          -- OID for the managed object
                 )

          The securityModel, securityName, and securityLevel parameters are
          set to the values that were recorded when the policy was modified.
          The viewType, contextName, and variableName parameters are set as
          appropriate for the requested SNMP operation.

       Unless all users who have write access to the pmPolicyTable and
       pmPolicyCodeTable have equivalent access to the managed system,
       policy scripts could be used by a user to gain the privileges of
       another user.  Therefore, when policy users have different access,
       access control should be applied so that a user's policies cannot be
       modified by another user.  To make this more convenient, a user can
       place all of his or her policies in the same pmPolicyAdminGroup so
       that a single access control view can apply to all of them.

       Some policies may be designed to ensure the security of a network.
       If these policies have not been installed pending the appearance of a
       role or capability, some delay will occur in their activation
       policies when the role or capability appears because a responsible
       manager must notice the change and install the policy.  This delay
       may expose the device or the network to unacceptable security
       vulnerabilities during this delay.  If the role or capability appears
       during a time of network stress or when the management station is
       unavailable, this delay could be extensive, further increasing the
       exposure.  It is recommended that management stations install any
       security-related policies that might ever be needed on a particular
       managed device, even if a nonexistent role or capability suggests
       that it is not needed at a given time.

       This MIB allows the delegation of access rights so that a user
       ("Joe") can instruct a Policy MIB agent to execute remote operations
       on his behalf that are authorized by keys stored by "Joe" into the
       usmUserTable.  Care needs to be taken to ensure that unauthorized
       users are unable to configure their policies to use Joe's keys.
       Although there are theoretically many ways to configure SNMP
       security, users are advised to follow the most straightforward way
       outlined below to minimize complexity and the resulting opportunity
       for errors.

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    RFC 4011              Policy Based Management MIB             March 2005

          Assume that Joe has credentials that give him authority to manage
          agents A, B, and C, as well as the Policy MIB agent "P".  Joe will
          store credentials for Joe@A, Joe@B, and Joe@C in the usmUserTable
          of the Policy MIB agent.  Then the following VACM configuration
          will be used:

             VACM securityToGroupTable
             A single entry mapping user Joe@P to group JoesGroup

             VACM accessTable
             A single entry mapping group JoesGroup to write view JoesView

             VACM viewTreeFamilyTable
             ViewName        Subtree                             Type
             JoesView        points to Joe@A in usmUserTable     included
             JoesView        points to Joe@B in usmUserTable     included
             JoesView        points to Joe@C in usmUserTable     included

          In the preceding examples, the notation Joe@A represents the entry
          indexed by usmUserEngineID and usmUserName, where the SnmpEngineID
          is that of system A and the usmUserName is "Joe".

    14.  IANA Considerations

       This is a profile of stringprep.  It has been registered by the IANA
       in the stringprep profile registry located at:

          http://www.iana.org/assignments/stringprep-profiles

          Name of this profile:
             Policy MIB Stringprep.

          RFC in which the profile is defined:
             This document.

             Indicator whether this is the newest version of the profile:

                This is the first version of Policy MIB Stringprep.

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    15.  Acknowledgements

       The authors gratefully acknowledge the significant contributions to
       this work made by Jeff Case, Patrik Falstrom, Joel Halpern, Pablo
       Halpern, Bob Moore, Steve Moulton, David Partain, and Walter Weiss.

       This MIB uses a security delegation mechanism that was first
       introduced in the DISMAN-SCHEDULE-MIB [12].  The Schedule table of
       this MIB borrows heavily from the PolicyTimePeriodCondition of the
       Policy Core Information Model (PCIM) [18] and from the DISMAN-
       SCHEDULE-MIB [12].

    16.  References

    16.1.  Normative References

       [1]  Harrington, D., Presuhn, R., and B. Wijnen, "An Architecture for
            Describing Simple Network Management Protocol (SNMP) Management
            Frameworks", STD 62, RFC 3411, December 2002.

       [2]  McCloghrie, K., Perkins, D., and J. Schoenwaelder, "Structure of
            Management Information Version 2 (SMIv2)", STD 58, RFC 2578,
            April 1999.

       [3]  McCloghrie, K., Perkins, D., and J. Schoenwaelder, "Textual
            Conventions for SMIv2", STD 58, RFC 2579, April 1999.

       [4]  McCloghrie, K., Perkins, D., and J. Schoenwaelder, "Conformance
            Statements for SMIv2", STD 58, RFC 2580, April 1999.

       [5]  Presuhn, R., "Transport Mappings for the Simple Network
            Management Protocol (SNMP)", STD 62, RFC 3417, December 2002.

       [6]  Blumenthal, U. and B. Wijnen, "User-based Security Model (USM)
            for version 3 of the Simple Network Management Protocol
            (SNMPv3)", STD 62, RFC 3414, December 2002.

       [7]  Presuhn, R., "Version 2 of the Protocol Operations for the
            Simple Network Management Protocol (SNMP)", STD 62, RFC 3416,
            December 2002.

       [8]  Frye, R., Levi, D., Routhier, S., and B. Wijnen, "Coexistence
            between Version 1, Version 2, and Version 3 of the Internet-
            standard Network Management Framework", BCP 74, RFC 3584, August
            2003.

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    RFC 4011              Policy Based Management MIB             March 2005

       [9]  Wijnen, B., Presuhn, R., and K. McCloghrie, "View-based Access
            Control Model (VACM) for the Simple Network Management Protocol
            (SNMP)", STD 62, RFC 3415, December 2002.

       [10] International Standards Organization, "Information Technology -
            Programming Languages - C++", ISO/IEC 14882-1998

       [11] Daniele, M. and J. Schoenwaelder, "Textual Conventions for
            Transport Addresses", RFC 3419, December 2002.

       [12] Levi, D. and J. Schoenwaelder, "Definitions of Managed Objects
            for Scheduling Management Operations", RFC 3231, January 2002.

       [13] Hoffman, P. and M. Blanchet, "Preparation of Internationalized
            Strings ("stringprep")", RFC 3454, December 2002.

       [14] Yergeau, F., "UTF-8, a transformation format of ISO 10646", STD
            63, RFC 3629, November 2003.

       [15] Dawson, F. and D. Stenerson, "Internet Calendaring and
            Scheduling Core Object Specification (iCalendar)", RFC 2445,
            November 1998.

    16.2.  Informative References

       [16] Case, J., Mundy, R., Partain, D., and B. Stewart, "Introduction
            and Applicability Statements for Internet-Standard Management
            Framework", RFC 3410, December 2002.

       [17] ECMA, "ECMAScript Language Specification", ECMA-262, December
            1999

       [18] Moore, B., Ellesson, E., Strassner, J., and A. Westerinen,
            "Policy Core Information Model -- Version 1 Specification", RFC
            3060, February 2001.

       [19] MacFaden, M., Partain, D., Saperia, J., and W. Tackabury,
            "Configuring Networks and Devices with Simple Network Management
            Protocol (SNMP)", RFC 3512, April 2003.

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    RFC 4011              Policy Based Management MIB             March 2005

    Author's Addresses

       Steve Waldbusser

       Phone: +1-650-948-6500
       Fax:   +1-650-745-0671
       EMail: waldbusser@nextbeacon.com

       Jon Saperia (WG Co-chair)
       JDS Consulting, Inc.
       84 Kettell Plain Road.
       Stow MA 01775
       USA

       Phone: +1-978-461--0249
       Fax:   +1-617-249-0874
       EMail: saperia@jdscons.com

       Thippanna Hongal
       Riverstone Networks, Inc.
       5200 Great America Parkway
       Santa Clara, CA, 95054
       USA

       Phone: +1-408-878-6562
       Fax:   +1-408-878-6501
       EMail: hongal@riverstonenet.com

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    RFC 4011              Policy Based Management MIB             March 2005

    Full Copyright Statement

       Copyright (C) The Internet Society (2005).

       This document is subject to the rights, licenses and restrictions
       contained in BCP 78, and except as set forth therein, the authors
       retain all their rights.

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    Acknowledgement

       Funding for the RFC Editor function is currently provided by the
       Internet Society.

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