    Network Working Group                                     J. Parker, Ed.
    Request for Comments: 4444                             Axiowave Networks
    Category: Standards Track                                     April 2006

                        Management Information Base for
               Intermediate System to Intermediate System (IS-IS)

    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 (2006).

    Abstract

       This memo defines a portion of the Management Information Base (MIB)
       for use with network management protocols in the Internet community.
       Specifically, this document describes a MIB for the Intermediate
       System to Intermediate System (IS-IS) Routing protocol when it is
       used to construct routing tables for IP networks.

    Table of Contents

       1. The Internet-Standard Management Framework . . . . . . . . . .   2
       2. Overview . . . . . . . . . . . . . . . . . . . . . . . . . . .   2
       3. Conventions  . . . . . . . . . . . . . . . . . . . . . . . . .   5
       4. Definition of IS-IS MIB. . . . . . . . . . . . . . . . . . . .   6
       5. IANA Considerations. . . . . . . . . . . . . . . . . . . . . .  96
       6. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . .  96
       7. Security Considerations. . . . . . . . . . . . . . . . . . . .  96
       8. Normative References . . . . . . . . . . . . . . . . . . . . . 101
       9. Informative References . . . . . . . . . . . . . . . . . . . . 102

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    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 [RFC3410].

       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 [RFC2578], STD 58, RFC 2579 [RFC2579] and STD 58, RFC 2580
       [RFC2580].

    2.  Overview

       This document describes a management information base for the
       Intermediate System to Intermediate System (IS-IS) Routing protocol,
       as described in ISO 10589 [ISO10589], when it is used to construct
       routing tables for IP networks, as described in RFC 1195 [RFC1195].
       The objects are mainly derived from the Guidelines for Definition of
       Managed Objects (GDMO) definitions in ISO 10589 and from the GDMO
       definitions in ISO 10733 [ISO10733].  There are also additional
       objects for managing the IP-specific functionality of Integrated IS-
       IS operation.

       This MIB imports definitions from SNMPv2-TC [RFC2579], SNMPv2-SMI
       [RFC2578], SNMPv2-CONF [RFC2580], SNMP-FRAMEWORK-MIB [RFC3411],
       DIFFSERV-MIB [RFC3289], IF-MIB [RFC2863], and INET-ADDRESS-MIB
       [RFC4001].  See the imports section of the MIB for the specific items
       imported.

       This MIB defines some objects to manage Mesh Groups, described in
       [RFC2973], and a three-way handshake for point-to-point adjacencies,
       described in [RFC3373].

       The IS-IS MIB defines the following objects:

       System-Wide Attributes

          -  isisSystem

             This table contains information specific to a single instance
             of the IS-IS protocol running on a router.

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          -  isisManAreaAddr

             This table includes area addresses that are manually
             configured, which are used to control the associations formed
             between Level 1 Intermediate Systems.

          -  isisAreaAddr

             This table includes area addresses reported in relevant L1
             LSPs.

          -  isisSummAddr

             This table holds summary addresses configured for each Level 2
             instance of the IS-IS protocol running on a router.

          -  isisRedistributeAddr

             This table provides criteria to decide whether a route should
             be leaked from L2 to L1 when Domain Wide Prefix leaking is
             enabled.

          -  isisRouter

             This table holds the hostname and router ID for Intermediate
             Systems in the network.

          -  isisSysLevel

             This table contains information specific to a domain (Level 2)
             or an area (Level 1) of the IS-IS protocol.

          -  isisNextCircIndex

             This scalar is used to provide a unique circuit index.

       Circuit-specific Attributes

          -  isisCirc

             This table contains information specific to a point-to-point or
             a broadcast interface in the system.

          -  isisCircLevel

             This table contains information specific to Level 1 or Level 2
             of an interface.

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       Counters

          -  isisSystemCounter

             Counters in the System table, such as number of times we have
             wrapped a sequence counter on one of our Link State PDUs.

          -  isisCircuitCounter

             Counters of events particular to a circuit, such as PDUs with
             an illegal value of the System ID field length.

          -  isisPacketCounter

             Counts of IS-IS Protocol PDUs broken down into packet type.

       Attributes associated with an Adjacency

          -  isisISAdj

             This table contains information about adjacencies to routers
             maintained by the protocol.  Entries in this table cannot be
             created by management action: they are established through the
             Hello protocol.

          -  isisISAdjAreaAddr

             This table contains the set of Area Addresses of neighboring
             Intermediate Systems, as reported in IIH PDUs.

          -  isisISAdjIPAddr

             This table contains the set of IP Addresses of neighboring
             Intermediate Systems, as reported in received IIH PDUs.

          -  isisISAdjProtSupp

             This table contains the set of protocols supported by
             neighboring Intermediate Systems, as reported in received IIH
             PDUs.

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       Attributes Associated with Addresses

          -  isisRA

             The Reachable Address Table.

             This table contains information about an address prefix
             manually configured on the system or learned through another
             protocol.

          -  isisIPRA

             The IP Reachable Address Table.

             This table contains information about an IP reachable address
             manually configured on this system or learned from another
             protocol.

       Attributes Associated with Link State PDU Table

          -  isisLSPSummaryTable

             The Link State PDU Summary Table.

             This table contains information contained in the headers of
             Link State PDUs stored by the system.

          -  isisLSPTLVTable

             The Link State PDU TLV Table.

             This table holds the sequence of TLVs that make up an LSP
             fragment.

       Attributes Associated with a Notification

          -  isisNotification

             This table defines attributes that will be included when
             reporting IS-IS notifications.

    3.  Conventions

       The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
       "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
       "OPTIONAL", when they appear in this document, are to be interpreted
       as described in BCP 14, RFC 2119 [RFC2119].

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    4.  Definition of IS-IS MIB

    ISIS-MIB DEFINITIONS ::= BEGIN
         IMPORTS
            TEXTUAL-CONVENTION, RowStatus, TruthValue, TimeStamp
                    FROM SNMPv2-TC               -- RFC2579
            MODULE-IDENTITY, OBJECT-TYPE, NOTIFICATION-TYPE,
                Unsigned32, Counter32, mib-2
                    FROM SNMPv2-SMI              -- RFC2578
            MODULE-COMPLIANCE, OBJECT-GROUP, NOTIFICATION-GROUP
                    FROM SNMPv2-CONF             -- RFC2580
            SnmpAdminString
                    FROM SNMP-FRAMEWORK-MIB      -- RFC2571
            IndexInteger, IndexIntegerNextFree
                    FROM DIFFSERV-MIB            -- RFC3289
            InterfaceIndex
                    FROM IF-MIB                  -- RFC2863
            InetAddressType, InetAddress, InetAddressPrefixLength
                    FROM INET-ADDRESS-MIB;       -- RFC3291

        isisMIB MODULE-IDENTITY
            LAST-UPDATED "200604040000Z" -- April 4, 2006, midnight
            ORGANIZATION "IETF IS-IS for IP Internets Working Group"
            CONTACT-INFO
                "IS-IS for IP Internets working Group
                 http://www.ietf.org/html.charters/isis-charter.html
                 isis-wg@ietf.org

                 Jeff Parker
                 Department of Computer Science
                 Middlebury College,
                 Middlebury, Vermont 05753
                 jeffp at middlbury dot edu"

            DESCRIPTION
                 "This document describes a management information base for
                 the IS-IS Routing protocol, as described in ISO 10589,
                 when it is used to construct routing tables for IP
                 networks, as described in RFC 1195.

                 This document is based on a 1994 IETF document by Chris
                 Gunner.  This version has been modified to include
                 current syntax, to exclude portions of the protocol that
                 are not relevant to IP, and to add management support for
                 current practice.

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                 Copyright (C) The Internet Society (2006).  This version
                 of this MIB module is part of RFC 4444; see the RFC
                 itself for full legal notices."

            REVISION "200604040000Z" -- April 4, 2006, midnight

            DESCRIPTION
                "Initial version, published as RFC 4444."
        ::= { mib-2 138 }

    -- Top-level structure of the MIB

    isisNotifications       OBJECT IDENTIFIER ::= { isisMIB 0 }
    isisObjects             OBJECT IDENTIFIER ::= { isisMIB 1 }
    isisConformance         OBJECT IDENTIFIER ::= { isisMIB 2 }

    -- OBJECT IDENTIFIER definitions

    -- System wide attributes.
    isisSystem OBJECT IDENTIFIER ::= { isisObjects 1 }

    -- Attributes associated with the domain or with the area.
    isisSysLevel OBJECT IDENTIFIER ::= { isisObjects 2 }

    -- Attributes associated with one Circuit
    isisCirc OBJECT IDENTIFIER ::= { isisObjects 3 }

    -- Attributes associated with area or domain relevant within a Circuit.
    isisCircLevelValues OBJECT IDENTIFIER ::= { isisObjects 4 }

    -- System and circuit counters.
    isisCounters OBJECT IDENTIFIER ::= { isisObjects 5 }

    -- Attributes associated with an adjacent Protocol Peer.
    isisISAdj OBJECT IDENTIFIER ::= { isisObjects 6 }

    -- Attributes associated with a configured address.
    isisReachAddr OBJECT IDENTIFIER ::= { isisObjects 7 }

    -- Attributes associated with IP routes learned by
    -- configuration or through another protocol.
    isisIPReachAddr OBJECT IDENTIFIER ::= { isisObjects 8 }

    -- The collection of Link State PDUs known to the Intermediate System
    isisLSPDataBase OBJECT IDENTIFIER ::= { isisObjects 9 }

    -- Objects included in Notifications.
    isisNotification OBJECT IDENTIFIER ::= { isisObjects 10 }

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    -- Type definitions

        IsisOSINSAddress ::= TEXTUAL-CONVENTION
            STATUS current
            DESCRIPTION
                "OSI Network Service Address, e.g., NSAP, SNPA, or Network
                 Entity Title"
            SYNTAX OCTET STRING (SIZE(0..20))

        IsisSystemID ::= TEXTUAL-CONVENTION
            STATUS current
            DESCRIPTION
                "The ID for an Intermediate System.  This should
                 be unique within a network, and is included
                 in all PDUs originated by an Intermediate System.
                 The protocol does not place any meanings upon
                 the bits, other than using ordering to break
                 ties in electing a Designated IS on a LAN."
            REFERENCE "{ISIS.aoi systemId (119)}"
            SYNTAX OCTET STRING (SIZE(6))

        IsisLinkStatePDUID ::= TEXTUAL-CONVENTION
            STATUS current
            DESCRIPTION
                "The 8-byte Link State PDU (LSP) ID,
                 consisting of the 6-byte SystemID of the
                 originating IS; a one-byte PseudoNode ID,
                 which is 0 unless the LSP represents the
                 topology of a LAN; and a one-byte LSP
                 fragment number that is issued in sequence,
                 starting with 0.  Non-zero PseudoNode IDs
                 need to be unique to the IS but need not
                 match the IfIndex."
            REFERENCE "{See section 9.8 of ISO 10589}"
            SYNTAX OCTET STRING (SIZE(8))

        IsisAdminState ::= TEXTUAL-CONVENTION
            STATUS current
            DESCRIPTION
                "Type used in enabling and disabling a row."
            SYNTAX INTEGER
                {
                    on(1),
                    off(2)
                }

        IsisLSPBuffSize ::= TEXTUAL-CONVENTION
            DISPLAY-HINT "d"

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            STATUS current
            DESCRIPTION
                "Integer sub-range for maximum LSP size."
            SYNTAX Unsigned32 (512..16000)

        IsisLevelState ::= TEXTUAL-CONVENTION
            STATUS current
            DESCRIPTION
                "States of the IS-IS protocol."
            SYNTAX INTEGER
                {
                    off (1),
                    on (2),
                    waiting (3),
                    overloaded(4)
                }

        IsisSupportedProtocol ::= TEXTUAL-CONVENTION
            STATUS current
            DESCRIPTION
                "Types of network protocol supported by Integrated IS-IS.
                 The values for ISO8473 and IP are those registered for
                 these protocols in ISO TR9577."
            REFERENCE "{See section 5.3.1 of RFC 1195}"
            SYNTAX INTEGER
                {
                    iso8473(129),
                    ipV6(142),
                    ip(204)
                }

        IsisDefaultMetric ::= TEXTUAL-CONVENTION
            DISPLAY-HINT "d"
            STATUS current
            DESCRIPTION
                "Integer sub-range for default metric for single hop.
                 ISO 10589 provides for 4 types of metric.  Only the
                 'default' metric is used in practice."
            REFERENCE "{See section 7.2.2 of ISO 10589}"
            SYNTAX Unsigned32 (0..63)

        IsisWideMetric ::= TEXTUAL-CONVENTION
            DISPLAY-HINT "d"
            STATUS current
            DESCRIPTION
                "Wide metric for IS Neighbors.  ISO 10589 provides a
                 6-bit metric.  Traffic Engineering extensions provide
                 24-bit metrics."

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            REFERENCE "{See section 3 of RFC 3784}"
            SYNTAX Unsigned32 (0..16777215)

        IsisFullMetric ::= TEXTUAL-CONVENTION
            DISPLAY-HINT "d"
            STATUS current
            DESCRIPTION
                "Full metric for IP Routes.  Traffic Engineering extensions
                 provide 32-bit metrics."
            REFERENCE "{See section 4 of RFC 3784}"
            SYNTAX Unsigned32

        IsisMetricType ::= TEXTUAL-CONVENTION
            STATUS current
            DESCRIPTION
                "Is this an Internal or External Metric?"
            REFERENCE "{See section 7.2.2 of ISO 10589}"
            SYNTAX INTEGER
                {
                    internal(1),
                    external(2)
                }

        IsisMetricStyle ::= TEXTUAL-CONVENTION
            STATUS current
            DESCRIPTION
                "Do we use RFC 1195 style metrics or wide metrics?"
            REFERENCE "{See section 5 of RFC 3787}"
            SYNTAX INTEGER
                {
                    narrow(1),
                    wide(2),
                    both(3)
                }

        IsisISLevel ::= TEXTUAL-CONVENTION
            STATUS current
            DESCRIPTION
                "Identifies a level."
            REFERENCE "{See definitions 3.6.1 and 3.6.11 of ISO 10589}"
            SYNTAX INTEGER
                {
                    area(1),        -- L1
                    domain(2)       -- L2
                }

        IsisLevel ::= TEXTUAL-CONVENTION
            STATUS current

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            DESCRIPTION
                "Identifies one or more levels."
            REFERENCE "{See definitions 3.6.1 and 3.6.11 of ISO 10589}"
            SYNTAX INTEGER
                {
                    level1(1),
                    level2(2),
                    level1and2(3)
                }

        IsisPDUHeader ::= TEXTUAL-CONVENTION
            STATUS current
            DESCRIPTION
                "A block to contain the header from a PDU."
            SYNTAX OCTET STRING (SIZE(0..64))

        IsisCircuitID ::= TEXTUAL-CONVENTION
            STATUS current
            DESCRIPTION
                "ID for a circuit."
            REFERENCE "{See section 7.2.7 of ISO 10589}"
            SYNTAX OCTET STRING (SIZE(0|7))

        IsisISPriority ::= TEXTUAL-CONVENTION
            DISPLAY-HINT "d"
            STATUS current
            DESCRIPTION
                "Integer sub-range for IS-IS priority."
            REFERENCE "{See section 9.5 of ISO 10589}"
            SYNTAX Unsigned32 (0..127)

        IsisUnsigned16TC ::= TEXTUAL-CONVENTION
            DISPLAY-HINT "d"
            STATUS current
            DESCRIPTION
                "An Unsigned32 further restricted to 16 bits.  Note that
                 the ASN.1 BER encoding may still require 24 bits for
                 some values."
            SYNTAX Unsigned32 (0..65535)

        IsisUnsigned8TC ::= TEXTUAL-CONVENTION
            DISPLAY-HINT "d"
            STATUS current
            DESCRIPTION
                "An Unsigned32 further restricted to 8 bits.  Note that
                 the ASN.1 BER encoding may still require 16 bits for
                 some values."
            SYNTAX Unsigned32 (0..255)

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    -- Behavior Definitions

    -- ResettingTimer behavior definition
    --

    -- "This behavior applies to objects that specify the interval
    -- between events in the operation of the protocol state machine.
    -- If the value of such an object is set to a new value while
    -- the protocol state machine is in operation, the implementation
    -- shall take the necessary steps to ensure that for any time
    -- interval that was in progress when the value of the
    -- corresponding object was changed, the next expiration of that
    -- interval takes place the specified time after the original
    -- start of that interval, or immediately, whichever is later.
    -- The precision with which this time shall be implemented shall
    -- be the same as that associated with the basic operation of
    -- the timer object."

    -- ReplaceOnlyWhileDisabled behavior definition
    -- "This behavior applies to objects that may not be modified
    -- while the corresponding table row's variable of type
    -- IsisAdminState is in state on."

    -- ManualOrAutomatic behavior definition
    -- "This behavior applies to objects that are read-write
    -- if the object was created manually.  Objects that were
    -- created automatically that have this behavior are
    -- read-only.

        isisSysObject  OBJECT IDENTIFIER ::= { isisSystem 1 }

        isisSysVersion OBJECT-TYPE
            SYNTAX INTEGER
                {
                    unknown(0),
                    one(1)
                }
            MAX-ACCESS read-only
            STATUS current
            DESCRIPTION
                "The version number of the IS-IS protocol that
                 is implemented."
            REFERENCE "{ISIS.aoi version (1)}"
            DEFVAL { one }
        ::= { isisSysObject 1 }

        isisSysLevelType OBJECT-TYPE
            SYNTAX IsisLevel

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            MAX-ACCESS read-write
            STATUS current
            DESCRIPTION
                "At which levels is the Intermediate System
                 running? This object may not be modified when
                 the isisSysAdminState variable is in state 'on'
                 for this Intermediate System.

                 Configured values MUST survive an agent reboot."
            REFERENCE "{ISIS.aoi iSType (2)}"
            DEFVAL { level1and2 }
        ::= { isisSysObject 2 }

        isisSysID OBJECT-TYPE
            SYNTAX IsisSystemID
            MAX-ACCESS read-write
            STATUS current
            DESCRIPTION
                "The ID for this Intermediate System.
                 This value is appended to each of the
                 area addresses to form the Network Entity Titles.
                 The derivation of a value for this object is
                 implementation specific.  Some implementations may
                 automatically assign values and not permit an
                 SNMP write, while others may require the value
                 to be set manually.

                 Configured values MUST survive an agent reboot."
            REFERENCE "{ISIS.aoi systemId (119)}"
        ::= { isisSysObject 3 }

        isisSysMaxPathSplits OBJECT-TYPE
            SYNTAX Unsigned32 (1..32)
            MAX-ACCESS read-write
            STATUS current
            DESCRIPTION
                "Maximum number of paths with equal routing metric value
                 which it is permitted to split between.  This object
                 may not be modified when the isisSysAdminState variable
                 is in state 'on' for this Intermediate System.

                 Configured values MUST survive an agent reboot."
            REFERENCE "{ISIS.aoi maximumPathSplits (3)}"
            DEFVAL { 2 }
        ::= { isisSysObject 4 }

        isisSysMaxLSPGenInt OBJECT-TYPE
            SYNTAX Unsigned32 (1..65235)

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            UNITS "seconds"
            MAX-ACCESS read-write
            STATUS current
            DESCRIPTION
                "Maximum interval, in seconds, between generated LSPs
                 by this Intermediate System.  This object follows
                 the ResettingTimer behavior.  The value must be
                 greater than any value configured for
                 isisSysLevelMinLSPGenInt, and should be at least 300
                 seconds less than isisSysMaxAge.

                 Configured values MUST survive an agent reboot."
            REFERENCE "{ISIS.aoi maximumLSPGenerationInterval (6)}"
            DEFVAL { 900 }
        ::= { isisSysObject 5 }

        isisSysPollESHelloRate OBJECT-TYPE
            SYNTAX IsisUnsigned16TC (1..65535)
            UNITS "seconds"
            MAX-ACCESS read-write
            STATUS current
            DESCRIPTION
                "The value, in seconds, to be used for the suggested ES
                 configuration timer in ISH PDUs when soliciting the ES
                 configuration.

                 Configured values MUST survive an agent reboot."
            REFERENCE "{ISIS.aoi pollESHelloRate (13)}"
            DEFVAL { 50 }
        ::= { isisSysObject 6 }

        isisSysWaitTime OBJECT-TYPE
            SYNTAX IsisUnsigned16TC (1..65535)
            UNITS "seconds"
            MAX-ACCESS read-write
            STATUS current
            DESCRIPTION
                "Number of seconds to delay in state 'waiting' before
                 entering the state 'on'.  This object follows the
                 ResettingTimer behavior.

                 Configured values MUST survive an agent reboot."
            REFERENCE "{ISIS.aoi waitingTime (15)}"
            DEFVAL { 60 }
        ::= { isisSysObject 7 }

        isisSysAdminState OBJECT-TYPE
            SYNTAX IsisAdminState

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            MAX-ACCESS read-write
            STATUS current
            DESCRIPTION
                "The administrative state of this Intermediate
                 System.  Setting this object to the value 'on'
                 when its current value is 'off' enables
                 the Intermediate System.

                 Configured values MUST survive an agent reboot."
            DEFVAL { off }
        ::= { isisSysObject 8 }

        isisSysL2toL1Leaking OBJECT-TYPE
            SYNTAX TruthValue
            MAX-ACCESS read-write
            STATUS current
            DESCRIPTION
                "If true, allow the router to leak L2 routes into L1.

                 Configured values MUST survive an agent reboot."
            DEFVAL { false }
        ::= { isisSysObject 9 }

        isisSysMaxAge OBJECT-TYPE
            SYNTAX IsisUnsigned16TC (350..65535)
            UNITS "seconds"
            MAX-ACCESS read-write
            STATUS current
            DESCRIPTION
                "Value to place in RemainingLifeTime field of
                 the LSPs we generate.
                 This should be at least 300 seconds greater than
                 isisSysMaxLSPGenInt.

                 Configured values MUST survive an agent reboot."
            DEFVAL { 1200 }
        ::= { isisSysObject 10 }

        isisSysReceiveLSPBufferSize OBJECT-TYPE
            SYNTAX IsisUnsigned16TC (1492..16000)
            UNITS "bytes"
            MAX-ACCESS read-write
            STATUS current
            DESCRIPTION
                "Size of the largest buffer we are designed or
                 configured to store.  This should be at least
                 as big as the maximum isisSysLevelOrigLSPBuffSize
                 supported by the system.

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                 If resources allow, we will store and flood LSPs
                 larger than isisSysReceiveLSPBufferSize, as this
                 can help avoid problems in networks with different
                 values for isisSysLevelOrigLSPBuffSize.

                 Configured values MUST survive an agent reboot."
            DEFVAL { 1492 }
        ::= { isisSysObject 11 }

        isisSysProtSupported OBJECT-TYPE
            SYNTAX BITS {
                        iso8473 (0),
                        ipv4 (1),
                        ipv6 (2)
                      }
            MAX-ACCESS read-only
            STATUS current
            DESCRIPTION
                "This attribute contains the set of protocols
                 supported by this Intermediate System."
        ::= { isisSysObject 12 }

        isisSysNotificationEnable OBJECT-TYPE
            SYNTAX TruthValue
            MAX-ACCESS read-write
            STATUS current
            DESCRIPTION
                "If this object is set to true(1), then it enables
                 the emission of IS-IS Notifications.  If it is
                 set to false(2), these notifications are not sent.

                 Configured values MUST survive an agent reboot."
            DEFVAL { true }
        ::= { isisSysObject 13 }

    -- The Level 1 Manual Area Address Table

        isisManAreaAddrTable OBJECT-TYPE
            SYNTAX SEQUENCE OF IsisManAreaAddrEntry
            MAX-ACCESS not-accessible
            STATUS current
            DESCRIPTION
                "The set of manual area addresses configured on this
                 Intermediate System.

                 At least one row in which the value of
                 isisManAreaAddrExistState is active must be present.
                 The maximum number of rows in this table for

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                 which the object isisManAreaAddrExistState has the
                 value active is 3.

                 An attempt to create more than 3 rows of
                 isisManAreaAddrEntry with state 'active' in one
                 instance of the IS-IS protocol should
                 return inconsistentValue."
            REFERENCE "{ISIS.aoi manualAreaAddresses (10)}"
        ::= { isisSystem 2 }

        isisManAreaAddrEntry OBJECT-TYPE
            SYNTAX IsisManAreaAddrEntry
            MAX-ACCESS not-accessible
            STATUS current
            DESCRIPTION
                "Each entry contains one area address manually configured
                 on this system.

                 Dynamically created rows MUST survive an agent reboot."
            INDEX { isisManAreaAddr }
        ::= { isisManAreaAddrTable 1 }

        IsisManAreaAddrEntry ::=
            SEQUENCE {
                isisManAreaAddr
                    IsisOSINSAddress,
                isisManAreaAddrExistState
                    RowStatus
                }

        isisManAreaAddr OBJECT-TYPE
            SYNTAX IsisOSINSAddress
            MAX-ACCESS not-accessible
            STATUS current
            DESCRIPTION
                "A manually configured area address for this system.

                 Note: An index for the entry {1, {49.0001} active} in
                 this table would be the ordered pair
                 (1, (0x03 0x49 0x00 0x01)), as the length of an octet
                 string is part of the OID."
        ::= { isisManAreaAddrEntry 1 }

        isisManAreaAddrExistState OBJECT-TYPE
            SYNTAX RowStatus
            MAX-ACCESS read-create
            STATUS current
            DESCRIPTION

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                "The state of the isisManAreaAddrEntry.  If the
                 isisSysAdminState for this Intermediate System is 'on' and
                 an attempt is made to set this object to the value
                 'destroy' or 'notInService' when this is the only
                 isisManAreaAddrEntry in state 'active' for this
                 Intermediate System should return inconsistentValue.

                 A row entry cannot be modified when the value of this
                 object is 'active'."
        ::= { isisManAreaAddrEntry 2 }

    -- The Level 1 Area Address Table

    -- The Level 1 Area Address Table contains the
    -- union of the sets of relevant area addresses configured
    -- or learned from Level 1 LSPs received by this Intermediate System.

        isisAreaAddrTable OBJECT-TYPE
            SYNTAX SEQUENCE OF IsisAreaAddrEntry
            MAX-ACCESS not-accessible
            STATUS current
            DESCRIPTION
                "The union of the sets of area addresses reported in all
                 Level 1 LSPs with fragment number zero generated by this
                 Intermediate System, or received from other Intermediate
                 Systems that are reachable via Level 1 routing."
            REFERENCE "{ISIS.aoi areaAddresses (18)}"
        ::= { isisSystem 3 }

        isisAreaAddrEntry OBJECT-TYPE
            SYNTAX IsisAreaAddrEntry
            MAX-ACCESS not-accessible
            STATUS current
            DESCRIPTION
                "Each entry contains one area address reported in a
                 Level 1 LSP generated or received by this Intermediate
                 System.

                 Dynamically learned rows do not survive an agent reboot."
            INDEX { isisAreaAddr }
        ::= { isisAreaAddrTable 1 }

        IsisAreaAddrEntry ::=
            SEQUENCE {
                isisAreaAddr
                    IsisOSINSAddress
                }

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        isisAreaAddr OBJECT-TYPE
            SYNTAX IsisOSINSAddress
            MAX-ACCESS read-only
            STATUS current
            DESCRIPTION
                "An area address reported in a Level 1 LSP."
        ::= { isisAreaAddrEntry 1 }

    -- The Summary Address Table

    -- The Summary Address Table contains the set of summary
    -- addresses manually configured for the Intermediate System.
    --
    -- This is used to control leaking L1 routes into L2.

        isisSummAddrTable OBJECT-TYPE
            SYNTAX SEQUENCE OF IsisSummAddrEntry
            MAX-ACCESS not-accessible
            STATUS current
            DESCRIPTION
                "The set of IP summary addresses to use in forming
                 summary TLVs originated by this Intermediate System.

                 An administrator may use a summary address to combine
                 and modify IP Reachability announcements.  If the
                 Intermediate system can reach any subset of the summary
                 address, the summary address MUST be announced instead,
                 at the configured metric."
        ::= { isisSystem 4 }

        isisSummAddrEntry OBJECT-TYPE
            SYNTAX IsisSummAddrEntry
            MAX-ACCESS not-accessible
            STATUS current
            DESCRIPTION
                "Each entry contains one IP summary address.

                 Dynamically created rows MUST survive an agent reboot.

                 Implementers need to be aware that if the total number
                 of elements (octets or sub-identifiers) in
                 isisSummAddress and isisSummAddrPrefixLen is too great,
                 then OIDs of column instances in this table will have
                 more than 128 subidentifiers and cannot be accessed
                 using SNMPv1, SNMPv2c, or SNMPv3."
            INDEX { isisSummAddressType,
                    isisSummAddress,
                    isisSummAddrPrefixLen }

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        ::= { isisSummAddrTable 1 }

        IsisSummAddrEntry ::=
            SEQUENCE {
                isisSummAddressType
                    InetAddressType,
                isisSummAddress
                    InetAddress,
                isisSummAddrPrefixLen
                    InetAddressPrefixLength,
                isisSummAddrExistState
                    RowStatus,
                isisSummAddrMetric
                    IsisDefaultMetric,
                isisSummAddrFullMetric
                    IsisFullMetric
            }

        isisSummAddressType OBJECT-TYPE
            SYNTAX InetAddressType
            MAX-ACCESS not-accessible
            STATUS current
            DESCRIPTION
                "The Type of IP address for this summary address."
        ::= { isisSummAddrEntry 1 }

        isisSummAddress OBJECT-TYPE
            SYNTAX InetAddress
            MAX-ACCESS not-accessible
            STATUS current
            DESCRIPTION
                "The IP Address value for this summary address.
                 The address must not contain any set host bits
                 (bits set after the address prefix determined by
                 isisSummAddrPrefixLen).

                 The type of this address is determined by the value of
                 the isisSummAddressType object."
        ::= { isisSummAddrEntry 2 }

        isisSummAddrPrefixLen OBJECT-TYPE
            SYNTAX InetAddressPrefixLength
            MAX-ACCESS not-accessible
            STATUS current
            DESCRIPTION
                "The Length of the IP NetMask for this summary address.

                 The values for the index objects isisSummAddress and

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                 isisSummAddrPrefixLen must be consistent.  When the value
                 of isisSummAddress (excluding the zone index, if one
                 is present) is x, then the bitwise logical-AND
                 of x with the value of the mask formed from the
                 corresponding index object isisSummAddrPrefixLen MUST be
                 equal to x.  If not, then the index pair is not
                 consistent, and an inconsistentName error must be
                 returned on SET or CREATE requests."
        ::= { isisSummAddrEntry 3 }

        isisSummAddrExistState OBJECT-TYPE
            SYNTAX RowStatus
            MAX-ACCESS read-create
            STATUS current
            DESCRIPTION
                "The existence state of this summary address.  Support
                 for 'createAndWait' and 'notInService' is not required.

                 A row entry cannot be modified when the value of this
                 object is 'active'."
        ::= { isisSummAddrEntry 4 }

        isisSummAddrMetric OBJECT-TYPE
            SYNTAX IsisDefaultMetric
            MAX-ACCESS read-create
            STATUS current
            DESCRIPTION
                "The metric value to announce this summary
                 address within LSPs generated by this system."
            DEFVAL { 20 }
        ::= { isisSummAddrEntry 5 }

        isisSummAddrFullMetric OBJECT-TYPE
            SYNTAX IsisFullMetric
            MAX-ACCESS read-create
            STATUS current
            DESCRIPTION
                "The wide metric value to announce this summary
                 address within LSPs generated by this system."
            DEFVAL { 20 }
        ::= { isisSummAddrEntry 6 }

    -- The Redistribution table defines addresses that should be
    -- leaked from L2 to L1 if isisSysL2toL1Leaking is enabled.

        isisRedistributeAddrTable OBJECT-TYPE
            SYNTAX SEQUENCE OF IsisRedistributeAddrEntry
            MAX-ACCESS not-accessible

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            STATUS current
            DESCRIPTION
                "This table provides criteria to decide if a route should
                 be leaked from L2 to L1 when Domain Wide Prefix leaking is
                 enabled.

                 Addresses that match the summary mask in the table MUST
                 be announced at L1 by routers when isisSysL2toL1Leaking
                 is enabled.  Routes that fall into the ranges specified
                 are announced as is, without being summarized.  Routes
                 that do not match a summary mask are not announced."
        ::= { isisSystem 5 }

        isisRedistributeAddrEntry OBJECT-TYPE
            SYNTAX IsisRedistributeAddrEntry
            MAX-ACCESS not-accessible
            STATUS current
            DESCRIPTION
                "Each entry contains one configured IP summary
                 address to manage leaking L2 addresses into L1.

                 Dynamically created rows MUST survive an agent reboot.

                 Implementers need to be aware that if the total number
                 of elements (octets or sub-identifiers) in
                 isisRedistributeAddrAddress and
                 isisRedistributeAddrPrefixLen is too great, then OIDs
                 of column instances in this table will have more than
                 128 subidentifiers and cannot be accessed using SNMPv1,
                 SNMPv2c, or SNMPv3."
            INDEX { isisRedistributeAddrType,
                    isisRedistributeAddrAddress,
                    isisRedistributeAddrPrefixLen }
        ::= { isisRedistributeAddrTable 1 }

        IsisRedistributeAddrEntry ::=
            SEQUENCE {
                isisRedistributeAddrType
                    InetAddressType,
                isisRedistributeAddrAddress
                    InetAddress,
                isisRedistributeAddrPrefixLen
                    InetAddressPrefixLength,
                isisRedistributeAddrExistState
                    RowStatus
            }

        isisRedistributeAddrType OBJECT-TYPE

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            SYNTAX InetAddressType
            MAX-ACCESS not-accessible
            STATUS current
            DESCRIPTION
                "The Type of IP address for this summary address."
        ::= { isisRedistributeAddrEntry 1 }

        isisRedistributeAddrAddress OBJECT-TYPE
            SYNTAX InetAddress
            MAX-ACCESS not-accessible
            STATUS current
            DESCRIPTION
                "The IP Address value for this summary address.
                 The type of this address is determined by the
                 value of the isisRedistributeAddrType object.
                 The address must not contain any set host bits -
                 bits set after the address prefix determined by
                 isisRedistributeAddrPrefixLen."

        ::= { isisRedistributeAddrEntry 2 }

        isisRedistributeAddrPrefixLen OBJECT-TYPE
            SYNTAX InetAddressPrefixLength
            MAX-ACCESS not-accessible
            STATUS current
            DESCRIPTION
                "The Length of the IP NetMask for this summary address.

                 The values for the index objects
                 isisRedistributeAddrAddress and
                 isisRedistributeAddrPrefixLen must be consistent.
                 When the value of isisRedistributeAddrAddress
                 (excluding the zone index, if one is present) is x,
                 then the bitwise logical-AND of x with the value of
                 the mask formed from the corresponding index object
                 isisRedistributeAddrPrefixLen MUST be equal to x.
                 If not, then the index pair is not consistent, and an
                 inconsistentName error must be returned on SET or
                 CREATE requests."

        ::= { isisRedistributeAddrEntry 3 }

        isisRedistributeAddrExistState OBJECT-TYPE
            SYNTAX RowStatus
            MAX-ACCESS read-create
            STATUS current
            DESCRIPTION
                "The existence state of this summary address.  Support

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                 for createAndWait and notInService is not required.

                 A row entry cannot be modified when the value of this
                 object is 'active'."
        ::= { isisRedistributeAddrEntry 4 }

    -- The Router Table keeps track of hostnames and router IDs
    -- associated with Intermediate Systems in the area and domain.

        isisRouterTable OBJECT-TYPE
            SYNTAX SEQUENCE OF IsisRouterEntry
            MAX-ACCESS not-accessible
            STATUS current
            DESCRIPTION
                "The set of hostnames and router ID."
        ::= { isisSystem 6 }

        isisRouterEntry OBJECT-TYPE
            SYNTAX IsisRouterEntry
            MAX-ACCESS not-accessible
            STATUS current
            DESCRIPTION
                "Each entry tracks information about one Intermediate
                 System at one level.

                 Dynamically learned rows do not survive an agent reboot."
            INDEX { isisRouterSysID,
                    isisRouterLevel }
        ::= { isisRouterTable 1 }

        IsisRouterEntry ::=
            SEQUENCE {
                isisRouterSysID
                    IsisSystemID,
                isisRouterLevel
                    IsisISLevel,
                isisRouterHostName
                    SnmpAdminString,
                isisRouterID
                    Unsigned32
            }

        isisRouterSysID OBJECT-TYPE
            SYNTAX IsisSystemID
            MAX-ACCESS not-accessible
            STATUS current
            DESCRIPTION
                "The System ID of the Intermediate System."

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        ::= { isisRouterEntry 1 }

        isisRouterLevel OBJECT-TYPE
            SYNTAX IsisISLevel
            MAX-ACCESS not-accessible
            STATUS current
            DESCRIPTION
                "The level at which the information about this
                 Intermediate System was received."
        ::= { isisRouterEntry 2 }

        isisRouterHostName OBJECT-TYPE
            SYNTAX SnmpAdminString
            MAX-ACCESS read-only
            STATUS current
            DESCRIPTION
                "The hostname listed in the LSP, or a zero-length
                 string if none."
        ::= { isisRouterEntry 3 }

        isisRouterID OBJECT-TYPE
            SYNTAX Unsigned32
            MAX-ACCESS read-only
            STATUS current
            DESCRIPTION
                "The Router ID found in the LSP, or zero if none."
        ::= { isisRouterEntry 4 }

    -- The System Level Table
    -- This table captures level-specific information about the system

        isisSysLevelTable OBJECT-TYPE
            SYNTAX SEQUENCE OF IsisSysLevelEntry
            MAX-ACCESS not-accessible
            STATUS current
            DESCRIPTION
                "Level specific information about the System."
        ::= { isisSysLevel 1 }

        isisSysLevelEntry OBJECT-TYPE
            SYNTAX IsisSysLevelEntry
            MAX-ACCESS not-accessible
            STATUS current
            DESCRIPTION
                "Each row describes variables configured for Area or Domain.

                 Configured values MUST survive an agent reboot."
            INDEX { isisSysLevelIndex }

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        ::= { isisSysLevelTable 1 }

        IsisSysLevelEntry ::=
            SEQUENCE {
                isisSysLevelIndex
                    IsisISLevel,
                isisSysLevelOrigLSPBuffSize
                    IsisLSPBuffSize,
                isisSysLevelMinLSPGenInt
                    IsisUnsigned16TC,
                isisSysLevelState
                    IsisLevelState,
                isisSysLevelSetOverload
                    TruthValue,
                isisSysLevelSetOverloadUntil
                    Unsigned32,
                isisSysLevelMetricStyle
                    IsisMetricStyle,
                isisSysLevelSPFConsiders
                    IsisMetricStyle,
                isisSysLevelTEEnabled
                    TruthValue
            }

        isisSysLevelIndex OBJECT-TYPE
            SYNTAX IsisISLevel
            MAX-ACCESS not-accessible
            STATUS current
            DESCRIPTION
                "The level that this entry describes."
        ::= { isisSysLevelEntry 1 }

        isisSysLevelOrigLSPBuffSize OBJECT-TYPE
            SYNTAX IsisLSPBuffSize
            MAX-ACCESS read-write
            STATUS current
            DESCRIPTION
                "The maximum size of LSPs and SNPs originated by
                 this Intermediate System at this level.  This
                 object may not be modified when the isisSysAdminState
                 variable is in state 'on' for this Intermediate System."
            REFERENCE "{ISIS.aoi originatingL1LSPBufferSize (9)}"
            DEFVAL { 1492 }
        ::= { isisSysLevelEntry 2 }

        isisSysLevelMinLSPGenInt OBJECT-TYPE
            SYNTAX IsisUnsigned16TC (1..65535)
            UNITS "seconds"

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            MAX-ACCESS read-write
            STATUS current
            DESCRIPTION
                "Minimum interval, in seconds, between successive
                 generation of LSPs with the same LSPID at this level
                 by this Intermediate System."
            REFERENCE "{ISIS.aoi minimumLSPGenerationInterval (11)}"
            DEFVAL { 30 }
        ::= { isisSysLevelEntry 3 }

        isisSysLevelState OBJECT-TYPE
            SYNTAX IsisLevelState
            MAX-ACCESS read-only
            STATUS current
            DESCRIPTION
                "The state of the database at this level.
                 The value 'off' indicates that IS-IS is not active at
                 this level.
                 The value 'on' indicates that IS-IS is active at this
                 level and is not overloaded.
                 The value 'waiting' indicates a database that is low on
                 an essential resource, such as memory.
                 The administrator may force the state to 'overloaded'
                 by setting the object isisSysLevelSetOverload.
                 If the state is 'waiting' or 'overloaded', we
                 originate LSPs with the overload bit set."
            REFERENCE "{ISIS.aoi l1State (17)}"
        ::= { isisSysLevelEntry 4 }

        isisSysLevelSetOverload OBJECT-TYPE
            SYNTAX TruthValue
            MAX-ACCESS read-write
            STATUS current
            DESCRIPTION
                "Administratively set the overload bit for the level.
                 The overload bit MUST continue to be set if the
                 implementation runs out of memory, independent of
                 this variable.  It may also be set manually independent
                 of this variable, using the isisSysLevelSetOverloadUntil
                 object."
            DEFVAL { false }
        ::= { isisSysLevelEntry 5 }

        isisSysLevelSetOverloadUntil OBJECT-TYPE
            SYNTAX Unsigned32
            UNITS "Seconds until clearing manually set Overload Bit"
            MAX-ACCESS read-write
            STATUS current

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            DESCRIPTION
                "If this object is non-zero, the overload bit is set at
                 this level when the isisSysAdminState variable goes to
                 state 'on' for this Intermediate System.  The overload bit
                 remains set for isisSysLevelSetOverloadUntil seconds.
                 When isisSysLevelSetOverloadUntil seconds have elapsed,
                 the overload flag remains set if the implementation has
                 run out of memory, or if it is set manually using the
                 isisSysLevelSetOverload object.

                 If isisSysLevelSetOverload is false, the system clears
                 the overload bit when isisSysLevelSetOverloadUntil seconds
                 have elapsed, if the system has not run out of memory."
        ::= { isisSysLevelEntry 6 }

        isisSysLevelMetricStyle OBJECT-TYPE
            SYNTAX IsisMetricStyle
            MAX-ACCESS read-write
            STATUS current
            DESCRIPTION
                "Which style of metric do we generate in our LSPs
                 at this level?"
            DEFVAL { narrow }
        ::= { isisSysLevelEntry 7 }

        isisSysLevelSPFConsiders OBJECT-TYPE
            SYNTAX IsisMetricStyle
            MAX-ACCESS read-write
            STATUS current
            DESCRIPTION
                "Which style of metric do we consider in our
                 SPF computation at this level?"
            DEFVAL { narrow }
        ::= { isisSysLevelEntry 8 }

        isisSysLevelTEEnabled OBJECT-TYPE
            SYNTAX TruthValue
            MAX-ACCESS read-write
            STATUS current
            DESCRIPTION
                "Do we do Traffic Engineering at this level?"
            DEFVAL { false }
        ::= { isisSysLevelEntry 9 }

    -- Static to provide next CircIndex

        isisNextCircIndex OBJECT-TYPE
            SYNTAX IndexIntegerNextFree

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            MAX-ACCESS read-only
            STATUS current
            DESCRIPTION
                "This object is used to assist a management
                 application in creating new rows in the
                 isisCircTable.  If it is possible to create
                 a new instance of isisCircEntry, then this
                 object will contain a non-zero value that
                 is not in use as the index of any row in the
                 isisCircTable.  The network manager reads the
                 value of this object and then (if the
                 value read is non-zero) attempts to create
                 the corresponding instance of isisCircEntry.
                 If the set request fails with the code
                 'inconsistentValue', then the process must be
                 repeated;  if the set request succeeds, then
                 the agent will change the value of this object
                 according to an implementation-specific
                 algorithm."
        ::= { isisCirc  1 }

    -- The Circuit Table
    -- Each broadcast or point-to-point interface on the system
    -- corresponds to one entry in the Circuit table.  However, there
    -- may be multiple X.25 DA circuit entries in the Circuit table
    -- for a given X.25 interface.

        isisCircTable OBJECT-TYPE
            SYNTAX SEQUENCE OF IsisCircEntry
            MAX-ACCESS not-accessible
            STATUS current
            DESCRIPTION
                "The table of circuits used by this
                 Intermediate System."
        ::= { isisCirc 2 }

        isisCircEntry OBJECT-TYPE
            SYNTAX IsisCircEntry
            MAX-ACCESS not-accessible
            STATUS current
            DESCRIPTION
                "An isisCircEntry exists for each circuit configured
                 for Integrated IS-IS on this system.

                 Dynamically created rows MUST survive an agent reboot."
            INDEX { isisCircIndex }
        ::= { isisCircTable 1 }

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        IsisCircEntry ::=
            SEQUENCE {
                isisCircIndex
                    IndexInteger,
                isisCircIfIndex
                    InterfaceIndex,
                isisCircAdminState
                    IsisAdminState,
                isisCircExistState
                    RowStatus,
                isisCircType
                    INTEGER,
                isisCircExtDomain
                    TruthValue,
                isisCircLevelType
                    IsisLevel,
                isisCircPassiveCircuit
                    TruthValue,
                isisCircMeshGroupEnabled
                    INTEGER,
                isisCircMeshGroup
                    Unsigned32,
                isisCircSmallHellos
                    TruthValue,
                isisCircLastUpTime
                    TimeStamp,
                isisCirc3WayEnabled
                    TruthValue,
                isisCircExtendedCircID
                    Unsigned32
            }

        isisCircIndex OBJECT-TYPE
            SYNTAX IndexInteger
            MAX-ACCESS not-accessible
            STATUS current
            DESCRIPTION
                "An index used to uniquely identify this circuit.
                 When creating a row in this table, the
                 isisNextCircIndex object should be retrieved,
                 and its value should be specified as the value
                 of this index using a SET operation.  A retrieved
                 value of zero(0) indicates that no rows can be
                 created at this time."
        ::= { isisCircEntry 1 }

        isisCircIfIndex OBJECT-TYPE
            SYNTAX InterfaceIndex

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            MAX-ACCESS read-create
            STATUS current
            DESCRIPTION
                "The value of ifIndex for the interface to which this
                 circuit corresponds.  This object cannot be modified
                 after creation."
        ::= { isisCircEntry 2 }

        isisCircAdminState OBJECT-TYPE
            SYNTAX IsisAdminState
            MAX-ACCESS read-create
            STATUS current
            DESCRIPTION
                "The administrative state of the circuit."
            DEFVAL { off }
        ::= { isisCircEntry 3 }

        isisCircExistState OBJECT-TYPE
            SYNTAX RowStatus
            MAX-ACCESS read-create
            STATUS current
            DESCRIPTION
                "The existence state of this circuit.  Setting the state
                 to 'notInService' halts the generation and processing of
                 IS-IS protocol PDUs on this circuit.  Setting the state
                 to destroy will also erase any configuration associated
                 with the circuit.  Support for 'createAndWait' and
                 'notInService' is not required.

                 A row entry cannot be modified when the value of this
                 object is 'active'."
        ::= { isisCircEntry 4 }

        isisCircType OBJECT-TYPE
            SYNTAX INTEGER
                {
                    broadcast(1),
                    ptToPt(2),
                    staticIn(3),
                    staticOut(4),
                    dA(5)
                }
            MAX-ACCESS read-create
            STATUS current
            DESCRIPTION
                "The type of the circuit.  This object follows the
                 ReplaceOnlyWhileDisabled behavior.  The type specified
                 must be compatible with the type of the interface defined

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                 by the value of isisCircIfIndex."
            REFERENCE "{ISIS.aoi type (33)}"
        ::= { isisCircEntry 5 }

        isisCircExtDomain OBJECT-TYPE
            SYNTAX TruthValue
            MAX-ACCESS read-create
            STATUS current
            DESCRIPTION
                "If true, suppress normal transmission of and
                 interpretation of Intra-domain IS-IS PDUs on this
                 circuit."
            REFERENCE "{ISIS.aoi externalDomain (46)}"
            DEFVAL { false }
        ::= { isisCircEntry 6 }

        isisCircLevelType OBJECT-TYPE
            SYNTAX IsisLevel
            MAX-ACCESS read-create
            STATUS current
            DESCRIPTION
                "Indicates which type of packets will be sent and
                 accepted on this circuit.  The values set will be
                 saved, but the values used will be modified by
                 the settings of isisSysLevelType.  Thus, if the
                 isisSysTpe is level2 and the isisCircLevelType
                 for a circuit is level1, the circuit will not send
                 or receive IS-IS packets.  This object follows the
                 ReplaceOnlyWhileDisabled behavior."
            DEFVAL { level1and2 }
        ::= { isisCircEntry 7 }

        isisCircPassiveCircuit OBJECT-TYPE
            SYNTAX TruthValue
            MAX-ACCESS read-create
            STATUS current
            DESCRIPTION
                "Should we include this interface in LSPs, even if
                 it is not running the IS-IS Protocol?"
            DEFVAL { false }
        ::= { isisCircEntry 8 }

        isisCircMeshGroupEnabled OBJECT-TYPE
            SYNTAX INTEGER
                {
                    inactive(1),
                    blocked(2),
                    set(3)

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                }
            MAX-ACCESS read-create
            STATUS current
            DESCRIPTION
                "Is this port a member of a mesh group, or is it
                 blocked?  Circuits in the same mesh group act as a
                 virtual multiaccess network.  LSPs seen on one circuit
                 in a mesh group will not be flooded to another circuit
                 in the same mesh group."
            REFERENCE "{ RFC 2973 }"
            DEFVAL { inactive }
        ::= { isisCircEntry 9 }

        isisCircMeshGroup OBJECT-TYPE
            SYNTAX Unsigned32
            MAX-ACCESS read-create
            STATUS current
            DESCRIPTION
                "Circuits in the same mesh group act as a virtual
                 multiaccess network.  LSPs seen on one circuit in
                 a mesh group will not be flooded to another circuit
                 in the same mesh group.  If isisCircMeshGroupEnabled
                 is inactive or blocked, this value is ignored."
            REFERENCE "{ RFC 2973 }"
        ::= { isisCircEntry 10 }

        isisCircSmallHellos OBJECT-TYPE
            SYNTAX TruthValue
            MAX-ACCESS read-create
            STATUS current
            DESCRIPTION
                "Can we send unpadded hellos on LAN circuits?  False
                 means the LAN Hellos must be padded.
                 Implementations should allow the administrator to read
                 this value.  An implementation need not be able to
                 support unpadded hellos to be conformant."
             DEFVAL { false }
        ::= { isisCircEntry 11 }

        isisCircLastUpTime OBJECT-TYPE
            SYNTAX TimeStamp
            MAX-ACCESS read-only
            STATUS current
            DESCRIPTION
                "How long the circuit has been enabled, measured in
                 hundredths of seconds since the last re-initialization
                 of the network management subsystem; 0 if the
                 circuit has never been 'on'."

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        ::= { isisCircEntry 12 }

        isisCirc3WayEnabled OBJECT-TYPE
            SYNTAX TruthValue
            MAX-ACCESS read-create
            STATUS current
            DESCRIPTION
                "Is this circuit enabled to run 3Way handshake?"
            DEFVAL { true }
        ::= { isisCircEntry 13 }

        isisCircExtendedCircID OBJECT-TYPE
            SYNTAX Unsigned32
            MAX-ACCESS read-create
            STATUS current
            DESCRIPTION
                "The value to be used as the extended circuit ID in
                 3Way handshake.  This value is only used if
                 isisCirc3WayEnabled is true, and it must be unique
                 across all circuits on this IS."
        ::= { isisCircEntry 14 }

    -- The Circuit Level Table
    -- This table captures level-specific information about a circuit

        isisCircLevelTable OBJECT-TYPE
            SYNTAX SEQUENCE OF IsisCircLevelEntry
            MAX-ACCESS not-accessible
            STATUS current
            DESCRIPTION
                "Level specific information about circuits used by IS-IS."
        ::= { isisCircLevelValues 1 }

        isisCircLevelEntry OBJECT-TYPE
            SYNTAX IsisCircLevelEntry
            MAX-ACCESS not-accessible
            STATUS current
            DESCRIPTION
                "An isisCircLevelEntry exists for each level on
                 each circuit configured for Integrated IS-IS on
                 this system.

                 Configured values MUST survive an agent reboot."
            INDEX { isisCircIndex,
                    isisCircLevelIndex }
        ::= { isisCircLevelTable 1 }

        IsisCircLevelEntry ::=

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            SEQUENCE {
                isisCircLevelIndex
                    IsisISLevel,
                isisCircLevelMetric
                    IsisDefaultMetric,
                isisCircLevelWideMetric
                    IsisWideMetric,
                isisCircLevelISPriority
                    IsisISPriority,
                isisCircLevelIDOctet
                    Unsigned32,
                isisCircLevelID
                    IsisCircuitID,
                isisCircLevelDesIS
                    IsisCircuitID,
                isisCircLevelHelloMultiplier
                    Unsigned32,
                isisCircLevelHelloTimer
                    Unsigned32,
                isisCircLevelDRHelloTimer
                    Unsigned32,
                isisCircLevelLSPThrottle
                    IsisUnsigned16TC,
                isisCircLevelMinLSPRetransInt
                    Unsigned32,
                isisCircLevelCSNPInterval
                    Unsigned32,
                isisCircLevelPartSNPInterval
                    Unsigned32
            }

        isisCircLevelIndex OBJECT-TYPE
            SYNTAX IsisISLevel
            MAX-ACCESS not-accessible
            STATUS current
            DESCRIPTION
                "The level that this entry describes."
        ::= { isisCircLevelEntry 1 }

        isisCircLevelMetric OBJECT-TYPE
            SYNTAX IsisDefaultMetric
            MAX-ACCESS read-write
            STATUS current
            DESCRIPTION
                "The metric value of this circuit for this level."
            REFERENCE "{ISIS.aoi l1DefaultMetric (35)}"
            DEFVAL { 10 }
        ::= { isisCircLevelEntry 2 }

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        isisCircLevelWideMetric OBJECT-TYPE
            SYNTAX IsisWideMetric
            MAX-ACCESS read-write
            STATUS current
            DESCRIPTION
                "The wide metric value of this circuit for this level."
            DEFVAL { 10 }
        ::= { isisCircLevelEntry 3 }

        isisCircLevelISPriority OBJECT-TYPE
            SYNTAX IsisISPriority
            MAX-ACCESS read-write
            STATUS current
            DESCRIPTION
                "The priority for becoming the LAN-Designated
                 Intermediate System at this level."
            REFERENCE "{ISIS.aoi l2IntermediateSystemPriority (73)}"
            DEFVAL { 64 }
        ::= { isisCircLevelEntry 4 }

        isisCircLevelIDOctet OBJECT-TYPE
            SYNTAX Unsigned32(0..255)
            MAX-ACCESS read-only
            STATUS current
            DESCRIPTION
                "A one-byte identifier for the circuit selected by the
                 Intermediate System.

                 On point-to-point circuits, the value is used as the Local
                 Circuit ID in point-to-point IIH PDUs transmitted on this
                 circuit.  In this case, values of isisCircLevelIDOctet do
                 not need to be unique.

                 For broadcast circuits, the value is used to generate the
                 LAN ID that will be used if this Intermediate System is
                 elected as the Designated IS on this circuit.  The value
                 is required to differ on LANs where the Intermediate System
                 is the Designated Intermediate System."
        ::= { isisCircLevelEntry 5 }

        isisCircLevelID OBJECT-TYPE
            SYNTAX IsisCircuitID
            MAX-ACCESS read-only
            STATUS current
            DESCRIPTION
                "On a point-to-point circuit with a fully initialized
                 adjacency to a peer IS, the value of this object is
                 the circuit ID negotiated during adjacency initialization.

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                 On a point to point circuit without such an adjacency,
                 the value is the concatenation of the local system ID
                 and the one-byte isisCircLevelIDOctet for this circuit,
                 i.e., the value that would be proposed for the circuit ID.
                 On other circuit types, the value returned is the zero-
                 length OCTET STRING."
            REFERENCE "{ISIS.aoi ptPtCircuitID (51)}"
        ::= { isisCircLevelEntry 6 }

        isisCircLevelDesIS OBJECT-TYPE
            SYNTAX IsisCircuitID
            MAX-ACCESS read-only
            STATUS current
            DESCRIPTION
                "The ID of the LAN-Designated Intermediate System
                 on this circuit at this level.  If, for any reason,
                 this system is not partaking in the relevant
                 Designated Intermediate System election process,
                 then the value returned is the zero-length OCTET STRING."
            REFERENCE "{ISIS.aoi l2DesignatedIntermediateSystem (75)}"
        ::= { isisCircLevelEntry 7 }

        isisCircLevelHelloMultiplier OBJECT-TYPE
            SYNTAX Unsigned32 (2..100)
            MAX-ACCESS read-write
            STATUS current
            DESCRIPTION
                "This value is multiplied by the corresponding HelloTimer,
                 and the result in seconds (rounded up) is used as the
                 holding time in transmitted hellos, to be used by
                 receivers of hello packets from this IS."
            REFERENCE "{ISIS.aoi iSISHelloTimer (45)}"
            DEFVAL { 10 }
        ::= { isisCircLevelEntry 8 }

        isisCircLevelHelloTimer OBJECT-TYPE
            SYNTAX Unsigned32 (10..600000)
            UNITS "milliseconds"
            MAX-ACCESS read-write
            STATUS current
            DESCRIPTION
                "Maximum period, in milliseconds, between IIH PDUs
                 on multiaccess networks at this level for LANs.
                 The value at L1 is used as the period between
                 Hellos on L1L2 point-to-point circuits.  Setting
                 this value at level 2 on an L1L2 point-to-point
                 circuit will result in an error of InconsistentValue.

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                 This object follows the ResettingTimer behavior."
            REFERENCE "{ISIS.aoi iSISHelloTimer (45)}"
            DEFVAL { 3000 }
        ::= { isisCircLevelEntry 9 }

        isisCircLevelDRHelloTimer OBJECT-TYPE
            SYNTAX Unsigned32 (10..120000)
            UNITS "milliseconds"
            MAX-ACCESS read-write
            STATUS current
            DESCRIPTION
                "Period, in milliseconds, between Hello PDUs on
                 multiaccess networks when this IS is the Designated
                 Intermediate System.  This object follows the
                 ResettingTimer behavior."
            REFERENCE "{ISIS.aoi iSISHelloTimer (45)}"
            DEFVAL { 1000 }
        ::= { isisCircLevelEntry 10 }

        isisCircLevelLSPThrottle OBJECT-TYPE
            SYNTAX IsisUnsigned16TC (1..65535)
            UNITS "milliseconds"
            MAX-ACCESS read-write
            STATUS current
            DESCRIPTION
                "Minimal interval of time, in milliseconds, between
                 transmissions of LSPs on an interface at this level."
            REFERENCE
                "{ISIS.aoi minimumBroadcastLSPTransmissionInterval (5)}"
            DEFVAL { 30 }
        ::= { isisCircLevelEntry 11 }

        isisCircLevelMinLSPRetransInt OBJECT-TYPE
            SYNTAX Unsigned32 (1..300)
            UNITS "seconds"
            MAX-ACCESS read-write
            STATUS current
            DESCRIPTION
                "Minimum interval, in seconds, between re-transmission of
                 an LSP at this level.  This object follows the
                 ResettingTimer behavior.

                 Note that isisCircLevelLSPThrottle controls
                 how fast we send back-to-back LSPs.  This variable
                 controls how fast we re-send the same LSP."
            REFERENCE "{ISIS.aoi minimumLSPTransmissionInterval (5)}"
            DEFVAL { 5 }
        ::= { isisCircLevelEntry 12 }

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        isisCircLevelCSNPInterval OBJECT-TYPE
            SYNTAX Unsigned32 (1..600)
            UNITS "seconds"
            MAX-ACCESS read-write
            STATUS current
            DESCRIPTION
                "Interval of time, in seconds, between periodic
                 transmission of a complete set of CSNPs on
                 multiaccess networks if this router is the
                 designated router at this level.
                 This object follows the ResettingTimer behavior."
            REFERENCE "{ISIS.aoi completeSNPInterval (8)}"
            DEFVAL { 10 }
        ::= { isisCircLevelEntry 13 }

        isisCircLevelPartSNPInterval OBJECT-TYPE
            SYNTAX Unsigned32 (1..120)
            UNITS "seconds"
            MAX-ACCESS read-write
            STATUS current
            DESCRIPTION
                "Minimum interval, in seconds, between sending Partial
                 Sequence Number PDUs at this level.  This object
                 follows the ResettingTimer behavior."
            REFERENCE "{ISIS.aoi partialSNPInterval (14)}"
            DEFVAL { 2 }
        ::= { isisCircLevelEntry 14 }

    -- isisSystemCounterTable keeps track of system-wide events.

        isisSystemCounterTable OBJECT-TYPE
            SYNTAX SEQUENCE OF IsisSystemCounterEntry
            MAX-ACCESS not-accessible
            STATUS current
            DESCRIPTION
                "System-wide counters for this Intermediate System."
        ::= { isisCounters 1 }

        isisSystemCounterEntry OBJECT-TYPE
            SYNTAX IsisSystemCounterEntry
            MAX-ACCESS not-accessible
            STATUS current
            DESCRIPTION
                "System-wide IS-IS counters."
            INDEX { isisSysStatLevel }
        ::= { isisSystemCounterTable 1 }

        IsisSystemCounterEntry ::=

    Parker                      Standards Track                    [Page 39]

    RFC 4444                       IS-IS MIB                      April 2006

            SEQUENCE {
                isisSysStatLevel
                    IsisISLevel,
                isisSysStatCorrLSPs
                    Counter32,
                isisSysStatAuthTypeFails
                    Counter32,
                isisSysStatAuthFails
                    Counter32,
                isisSysStatLSPDbaseOloads
                    Counter32,
                isisSysStatManAddrDropFromAreas
                    Counter32,
                isisSysStatAttmptToExMaxSeqNums
                    Counter32,
                isisSysStatSeqNumSkips
                    Counter32,
                isisSysStatOwnLSPPurges
                    Counter32,
                isisSysStatIDFieldLenMismatches
                    Counter32,
                isisSysStatPartChanges
                    Counter32,
                isisSysStatSPFRuns
                    Counter32,
                isisSysStatLSPErrors
                    Counter32
            }

        isisSysStatLevel OBJECT-TYPE
            SYNTAX IsisISLevel
            MAX-ACCESS not-accessible
            STATUS current
            DESCRIPTION
                "The level that this entry describes."
        ::= { isisSystemCounterEntry 1 }

        isisSysStatCorrLSPs OBJECT-TYPE
            SYNTAX Counter32
            UNITS "Number of corrupted in-memory frames"
            MAX-ACCESS read-only
            STATUS current
            DESCRIPTION
                "Number of corrupted in-memory LSPs detected.

                 LSPs received from the wire with a bad checksum
                 are silently dropped and are not counted.

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                 LSPs received from the wire with parse errors
                 are counted by isisSysStatLSPErrors."
            REFERENCE "{ISIS.aoi corruptedLSPsDetected (19)}"
        ::= { isisSystemCounterEntry 2 }

        isisSysStatAuthTypeFails OBJECT-TYPE
            SYNTAX Counter32
            UNITS "Number of frames with authentication type mismatches"
            MAX-ACCESS read-only
            STATUS current
            DESCRIPTION
                "The number of authentication type mismatches recognized
                 by this Intermediate System."
        ::= { isisSystemCounterEntry 3 }

        isisSysStatAuthFails OBJECT-TYPE
            SYNTAX Counter32
            UNITS "Number of frames with authentication key failures"
            MAX-ACCESS read-only
            STATUS current
            DESCRIPTION
                "The number of authentication key failures recognized
                 by this Intermediate System."
        ::= { isisSystemCounterEntry 4 }

        isisSysStatLSPDbaseOloads OBJECT-TYPE
            SYNTAX Counter32
            MAX-ACCESS read-only
            STATUS current
            DESCRIPTION
                "Number of times the LSP database has become
                 overloaded."
            REFERENCE "{ISIS.aoi lSPL1DatabaseOverloads (20)}"
        ::= { isisSystemCounterEntry 5 }

        isisSysStatManAddrDropFromAreas OBJECT-TYPE
            SYNTAX Counter32
            MAX-ACCESS read-only
            STATUS current
            DESCRIPTION
                "Number of times a manual address has been dropped from
                 the area."
            REFERENCE "{ISIS.aoi manualAddressesDroppedFromArea (21)}"
        ::= { isisSystemCounterEntry 6 }

        isisSysStatAttmptToExMaxSeqNums OBJECT-TYPE
            SYNTAX Counter32
            MAX-ACCESS read-only

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            STATUS current
            DESCRIPTION
                "Number of times the IS has attempted to exceed the
                 maximum sequence number."
            REFERENCE
                "{ISIS.aoi attemptsToExceedmaximumSequenceNumber (22)}"
        ::= { isisSystemCounterEntry 7 }

        isisSysStatSeqNumSkips OBJECT-TYPE
            SYNTAX Counter32
            MAX-ACCESS read-only
            STATUS current
            DESCRIPTION
                "Number of times a sequence number skip has occurred."
            REFERENCE "{ISIS.aoi sequenceNumberSkips (23)}"
        ::= { isisSystemCounterEntry 8 }

        isisSysStatOwnLSPPurges OBJECT-TYPE
            SYNTAX Counter32
            MAX-ACCESS read-only
            STATUS current
            DESCRIPTION
                "Number of times a zero-aged copy of the system's own LSP
                 is received from some other node."
            REFERENCE "{ISIS.aoi ownLSPPurges (24)}"
        ::= { isisSystemCounterEntry 9 }

        isisSysStatIDFieldLenMismatches OBJECT-TYPE
            SYNTAX Counter32
            UNITS "Number of frames with ID length mismatches"
            MAX-ACCESS read-only
            STATUS current
            DESCRIPTION
                "Number of times a PDU is received with a different value
                 for ID field length from that of the receiving system."
            REFERENCE "{ISIS.aoi iDFieldLengthMismatches (25)}"
        ::= { isisSystemCounterEntry 10 }

        isisSysStatPartChanges OBJECT-TYPE
            SYNTAX Counter32
            MAX-ACCESS read-only
            STATUS current
            DESCRIPTION
                "Partition changes."
        ::= { isisSystemCounterEntry 11 }

        isisSysStatSPFRuns OBJECT-TYPE
            SYNTAX Counter32

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    RFC 4444                       IS-IS MIB                      April 2006

            MAX-ACCESS read-only
            STATUS current
            DESCRIPTION
                "Number of times we ran SPF at this level."
        ::= { isisSystemCounterEntry 12 }

        isisSysStatLSPErrors OBJECT-TYPE
            SYNTAX Counter32
            UNITS "Number of frames with errors that we have received"
            MAX-ACCESS read-only
            STATUS current
            DESCRIPTION
                "Number of LSPs with errors we have received."
        ::= { isisSystemCounterEntry 13 }

    -- isisCircuitCounterTable keeps track of events
    -- specific to a circuit and a level

        isisCircuitCounterTable OBJECT-TYPE
            SYNTAX SEQUENCE OF IsisCircuitCounterEntry
            MAX-ACCESS not-accessible
            STATUS current
            DESCRIPTION
                "Circuit specific counters for this
                 Intermediate System."
        ::= { isisCounters 2 }

        isisCircuitCounterEntry OBJECT-TYPE
            SYNTAX IsisCircuitCounterEntry
            MAX-ACCESS not-accessible
            STATUS current
            DESCRIPTION
                "An isisCircuitCounterEntry exists for each circuit
                 used by Integrated IS-IS on this system."
            INDEX { isisCircIndex,
                    isisCircuitType }
        ::= { isisCircuitCounterTable 1 }

        IsisCircuitCounterEntry ::= SEQUENCE {
              isisCircuitType
                  INTEGER,
              isisCircAdjChanges
                  Counter32,
              isisCircNumAdj
                  Unsigned32,
              isisCircInitFails
                  Counter32,
              isisCircRejAdjs

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    RFC 4444                       IS-IS MIB                      April 2006

                  Counter32,
              isisCircIDFieldLenMismatches
                  Counter32,
              isisCircMaxAreaAddrMismatches
                  Counter32,
              isisCircAuthTypeFails
                  Counter32,
              isisCircAuthFails
                  Counter32,
              isisCircLANDesISChanges
                  Counter32
           }

        isisCircuitType OBJECT-TYPE
            SYNTAX INTEGER
                {
                    lanlevel1(1),
                    lanlevel2(2),
                    p2pcircuit(3)
                }
            MAX-ACCESS not-accessible
            STATUS current
            DESCRIPTION
                "What type of circuit saw these counts?

                 The point-to-point Hello PDU includes
                 both L1 and L2, and ISs form a single
                 adjacency on point-to-point links.
                 Thus, we combine counts on
                 point-to-point links into one group."
        ::= { isisCircuitCounterEntry 1 }

        isisCircAdjChanges OBJECT-TYPE
            SYNTAX Counter32
            MAX-ACCESS read-only
            STATUS current
            DESCRIPTION
                "The number of times an adjacency state change has
                 occurred on this circuit."
            REFERENCE "{ISIS.aoi changesInAdjacencyState (40)}"
        ::= { isisCircuitCounterEntry 2 }

        isisCircNumAdj OBJECT-TYPE
            SYNTAX Unsigned32
            MAX-ACCESS read-only
            STATUS current
            DESCRIPTION
                "The number of adjacencies on this circuit."

    Parker                      Standards Track                    [Page 44]

    RFC 4444                       IS-IS MIB                      April 2006

            REFERENCE "{ISIS.aoi changesInAdjacencyState (40)}"
        ::= { isisCircuitCounterEntry 3 }

        isisCircInitFails OBJECT-TYPE
            SYNTAX Counter32
            MAX-ACCESS read-only
            STATUS current
            DESCRIPTION
                "The number of times initialization of this circuit has
                 failed.  This counts events such as PPP NCP failures.
                 Failures to form an adjacency are counted by
                 isisCircRejAdjs."
        ::= { isisCircuitCounterEntry 4 }

        isisCircRejAdjs OBJECT-TYPE
            SYNTAX Counter32
            MAX-ACCESS read-only
            STATUS current
            DESCRIPTION
                "The number of times an adjacency has been rejected on
                 this circuit."
            REFERENCE "{ISIS.aoi rejectedAdjacencies (42)}"
        ::= { isisCircuitCounterEntry 5 }

        isisCircIDFieldLenMismatches OBJECT-TYPE
            SYNTAX Counter32
            UNITS "Number of frames with ID field length mismatch"
            MAX-ACCESS read-only
            STATUS current
            DESCRIPTION
                "The number of times an IS-IS control PDU with an ID
                 field length different from that for this system has been
                 received."
            REFERENCE "{ISIS.aoi iDFieldLengthMismatches (25)}"
        ::= { isisCircuitCounterEntry 6 }

        isisCircMaxAreaAddrMismatches OBJECT-TYPE
            SYNTAX Counter32
            MAX-ACCESS read-only
            STATUS current
            DESCRIPTION
                "The number of times an IS-IS control PDU with a
                 max area address field different from that for this
                 system has been received."
            REFERENCE "{ISIS.aoi iDFieldLengthMismatches (25)}"
        ::= { isisCircuitCounterEntry 7 }

        isisCircAuthTypeFails OBJECT-TYPE

    Parker                      Standards Track                    [Page 45]

    RFC 4444                       IS-IS MIB                      April 2006

            SYNTAX Counter32
            MAX-ACCESS read-only
            STATUS current
            DESCRIPTION
                "The number of times an IS-IS control PDU with
                 an auth type field different from that for this
                 system has been received."
        ::= { isisCircuitCounterEntry 8 }

        isisCircAuthFails OBJECT-TYPE
            SYNTAX Counter32
            MAX-ACCESS read-only
            STATUS current
            DESCRIPTION
                "The number of times an IS-IS control PDU with
                 the correct auth type has failed to pass authentication
                 validation."
        ::= { isisCircuitCounterEntry 9 }

        isisCircLANDesISChanges OBJECT-TYPE
            SYNTAX Counter32
            MAX-ACCESS read-only
            STATUS current
            DESCRIPTION
                "The number of times the Designated IS has changed
                 on this circuit at this level.  If the circuit is
                 point to point, this count is zero."
        ::= { isisCircuitCounterEntry 10 }

    -- isisPacketCounterTable keeps track of the number of IS-IS
    -- control packets sent and received at each level

        isisPacketCounterTable OBJECT-TYPE
            SYNTAX SEQUENCE OF IsisPacketCounterEntry
            MAX-ACCESS not-accessible
            STATUS current
            DESCRIPTION
                "Information about IS-IS protocol traffic at one level,
                 on one circuit, in one direction."
        ::= { isisCounters 3 }

        isisPacketCounterEntry OBJECT-TYPE
            SYNTAX IsisPacketCounterEntry
            MAX-ACCESS not-accessible
            STATUS current
            DESCRIPTION
                "Information about IS-IS protocol traffic at one level,
                 on one circuit, in one direction."

    Parker                      Standards Track                    [Page 46]

    RFC 4444                       IS-IS MIB                      April 2006

            INDEX { isisCircIndex,
                    isisPacketCountLevel,
                    isisPacketCountDirection }
        ::= { isisPacketCounterTable 1 }

        IsisPacketCounterEntry ::=
            SEQUENCE {
                isisPacketCountLevel
                    IsisISLevel,
                isisPacketCountDirection
                    INTEGER,
                isisPacketCountIIHello
                    Counter32,
                isisPacketCountISHello
                    Counter32,
                isisPacketCountESHello
                    Counter32,
                isisPacketCountLSP
                    Counter32,
                isisPacketCountCSNP
                    Counter32,
                isisPacketCountPSNP
                    Counter32,
                isisPacketCountUnknown
                    Counter32
        }

        isisPacketCountLevel OBJECT-TYPE
            SYNTAX IsisISLevel
            MAX-ACCESS not-accessible
            STATUS current
            DESCRIPTION
                "The level at which these PDU counts have been collected."
        ::= { isisPacketCounterEntry 1 }

        isisPacketCountDirection OBJECT-TYPE
            SYNTAX INTEGER
                {
                    sending(1),
                    receiving(2)
                }
            MAX-ACCESS not-accessible
            STATUS current
            DESCRIPTION
                "Were we sending or receiving these PDUs?"
        ::= { isisPacketCounterEntry 2 }

        isisPacketCountIIHello OBJECT-TYPE

    Parker                      Standards Track                    [Page 47]

    RFC 4444                       IS-IS MIB                      April 2006

            SYNTAX Counter32
            UNITS "Number of IS-IS Hellos frames seen in this direction
                  at this level"
            MAX-ACCESS read-only
            STATUS current
            DESCRIPTION
                "The number of IS-IS Hello PDUs seen in this
                 direction at this level.

                 Point-to-Point IIH PDUs are counted at
                 the lowest enabled level: at L1 on L1 or L1L2 circuits,
                 and at L2 otherwise."
            REFERENCE "{ISIS.aoi iSISControlPDUsSent (43)}"
        ::= { isisPacketCounterEntry 3 }

        isisPacketCountISHello OBJECT-TYPE
            SYNTAX Counter32
            UNITS "Number of ES-IS frames seen in this direction at
                 this level."
            MAX-ACCESS read-only
            STATUS current
            DESCRIPTION
                "The number of ES-IS Hello PDUs seen in this
                 direction.  ISH PDUs are counted at the
                 lowest enabled level: at L1 on L1 or L1L2
                 circuits, and at L2 otherwise."
        ::= { isisPacketCounterEntry 4 }

        isisPacketCountESHello OBJECT-TYPE
            SYNTAX Counter32
            UNITS "Number of ES Hello frames seen in this direction at
                 this level"
            MAX-ACCESS read-only
            STATUS current
            DESCRIPTION
                "The number of ES Hello PDUs seen in this
                 direction.  ESH PDUs are counted at the
                 lowest enabled level: at L1 on L1 or L1L2
                 circuits, and at L2 otherwise."
        ::= { isisPacketCounterEntry 5 }

        isisPacketCountLSP OBJECT-TYPE
            SYNTAX Counter32
            UNITS "Number of IS-IS LSP frames seen in this direction at
                 this level"
            MAX-ACCESS read-only
            STATUS current
            DESCRIPTION

    Parker                      Standards Track                    [Page 48]

    RFC 4444                       IS-IS MIB                      April 2006

                "The number of IS-IS LSPs seen in this
                 direction at this level."
            REFERENCE "{ISIS.aoi iSISControlPDUsSent (43)}"
        ::= { isisPacketCounterEntry 6 }

        isisPacketCountCSNP OBJECT-TYPE
            SYNTAX Counter32
            UNITS "Number of IS-IS CSNP frames seen in this direction at
                 this level"
            MAX-ACCESS read-only
            STATUS current
            DESCRIPTION
                "The number of IS-IS CSNPs seen in this
                 direction at this level."
            REFERENCE "{ISIS.aoi iSISControlPDUsSent (43)}"
        ::= { isisPacketCounterEntry 7 }

        isisPacketCountPSNP OBJECT-TYPE
            SYNTAX Counter32
            UNITS "Number of IS-IS PSNP frames seen in this direction at
                 this level"
            MAX-ACCESS read-only
            STATUS current
            DESCRIPTION
                "The number of IS-IS PSNPs seen in this
                 direction at this level."
            REFERENCE "{ISIS.aoi iSISControlPDUsSent (43)}"
        ::= { isisPacketCounterEntry 8 }

        isisPacketCountUnknown OBJECT-TYPE
            SYNTAX Counter32
            UNITS "Number of unknown IS-IS frames seen at this level"
            MAX-ACCESS read-only
            STATUS current
            DESCRIPTION
                "The number of unknown IS-IS PDUs seen
                 at this level."
            REFERENCE "{ISIS.aoi iSISControlPDUsSent (43)}"
        ::= { isisPacketCounterEntry 9 }

    -- The IS Adjacency Table
    --
    -- Each adjacency to an IS corresponds to one entry in this
    -- table.

        isisISAdjTable OBJECT-TYPE
            SYNTAX SEQUENCE OF IsisISAdjEntry
            MAX-ACCESS not-accessible

    Parker                      Standards Track                    [Page 49]

    RFC 4444                       IS-IS MIB                      April 2006

            STATUS current
            DESCRIPTION
                "The table of adjacencies to Intermediate Systems."
        ::= { isisISAdj 1 }

        isisISAdjEntry OBJECT-TYPE
            SYNTAX IsisISAdjEntry
            MAX-ACCESS not-accessible
            STATUS current
            DESCRIPTION
                "Each entry corresponds to one adjacency to an
                 Intermediate System on this system.

                 Dynamically learned rows do not survive an agent reboot."
            INDEX { isisCircIndex,
                    isisISAdjIndex }
        ::= { isisISAdjTable 1 }

        IsisISAdjEntry ::=
            SEQUENCE {
                isisISAdjIndex
                    Unsigned32,
                isisISAdjState
                    INTEGER,
                isisISAdj3WayState
                    INTEGER,
                isisISAdjNeighSNPAAddress
                    IsisOSINSAddress,
                isisISAdjNeighSysType
                    INTEGER,
                isisISAdjNeighSysID
                    IsisSystemID,
                isisISAdjNbrExtendedCircID
                    Unsigned32,
                isisISAdjUsage
                    IsisLevel,
                isisISAdjHoldTimer
                    IsisUnsigned16TC,
                isisISAdjNeighPriority
                    IsisISPriority,
                isisISAdjLastUpTime
                    TimeStamp
          }

        isisISAdjIndex OBJECT-TYPE
            SYNTAX Unsigned32(1..4294967295)
            MAX-ACCESS not-accessible
            STATUS current

    Parker                      Standards Track                    [Page 50]

    RFC 4444                       IS-IS MIB                      April 2006

            DESCRIPTION
                "A unique value identifying the IS adjacency from all
                 other such adjacencies on this circuit.  This value is
                 automatically assigned by the system when the adjacency
                 is created."
        ::= { isisISAdjEntry 1 }

        isisISAdjState OBJECT-TYPE
            SYNTAX INTEGER
                {
                     down (1),
                     initializing (2),
                     up (3),
                     failed(4)
                }
            MAX-ACCESS read-only
            STATUS current
            DESCRIPTION
                "The state of the adjacency."
            REFERENCE "{ISIS.aoi adjacencyState (78)}"
        ::= { isisISAdjEntry 2 }

        isisISAdj3WayState OBJECT-TYPE
            SYNTAX INTEGER
                {
                     up (0),
                     initializing (1),
                     down (2),
                     failed (3)
                }
            MAX-ACCESS read-only
            STATUS current
            DESCRIPTION
                "The 3Way state of the adjacency.  These are picked
                 to match the historical on-the-wire representation
                 of the 3Way state and are not intended to match
                 isisISAdjState."
            REFERENCE "{ RFC 3373 }"
        ::= { isisISAdjEntry 3 }

        isisISAdjNeighSNPAAddress OBJECT-TYPE
            SYNTAX IsisOSINSAddress
            MAX-ACCESS read-only
            STATUS current
            DESCRIPTION
                "The SNPA address of the neighboring system."
            REFERENCE "{ISIS.aoi neighbourSNPAAddress (79)}"
        ::= { isisISAdjEntry 4 }

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        isisISAdjNeighSysType OBJECT-TYPE
            SYNTAX INTEGER
                {
                    l1IntermediateSystem(1),
                    l2IntermediateSystem(2),
                    l1L2IntermediateSystem(3),
                    unknown(4)
                }
            MAX-ACCESS read-only
            STATUS current
            DESCRIPTION
                "The type of the neighboring system."
            REFERENCE "{ISIS.aoi neighbourSystemType (80)}"
        ::= { isisISAdjEntry 5 }

        isisISAdjNeighSysID OBJECT-TYPE
            SYNTAX IsisSystemID
            MAX-ACCESS read-only
            STATUS current
            DESCRIPTION
                "The system ID of the neighboring Intermediate
                 System."
            REFERENCE "{ISIS.aoi neighbourSystemIds (83)}"
        ::= { isisISAdjEntry 6 }

        isisISAdjNbrExtendedCircID OBJECT-TYPE
            SYNTAX Unsigned32
            MAX-ACCESS read-only
            STATUS current
            DESCRIPTION
                "The 4-byte Extended Circuit ID learned from the
                 Neighbor during 3-way handshake, or 0."
        ::= { isisISAdjEntry 7 }

        isisISAdjUsage OBJECT-TYPE
            SYNTAX IsisLevel
            MAX-ACCESS read-only
            STATUS current
            DESCRIPTION
                "How is the adjacency used?  On a point-to-point link,
                 this might be level1and2, but on a LAN, the usage will
                 be level1 on the adjacency between peers at L1,
                 and level2 for the adjacency between peers at L2."
            REFERENCE "{ISIS.aoi adjacencyUsage (82)}"
        ::= { isisISAdjEntry 8 }

        isisISAdjHoldTimer OBJECT-TYPE
            SYNTAX IsisUnsigned16TC (1..65535)

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            UNITS "seconds"
            MAX-ACCESS read-only
            STATUS current
            DESCRIPTION
                "The holding time, in seconds, for this adjacency.
                 This value is based on received IIH PDUs and
                 the elapsed time since receipt."
            REFERENCE "{ISIS.aoi holdingTimer (85)}"
        ::= { isisISAdjEntry 9 }

        isisISAdjNeighPriority OBJECT-TYPE
            SYNTAX IsisISPriority
            MAX-ACCESS read-only
            STATUS current
            DESCRIPTION
                "Priority of the neighboring Intermediate System for
                 becoming the Designated Intermediate System."
            REFERENCE "{ISIS.aoi lANPriority (86)}"
        ::= { isisISAdjEntry 10 }

        isisISAdjLastUpTime OBJECT-TYPE
            SYNTAX TimeStamp
            MAX-ACCESS read-only
            STATUS current
            DESCRIPTION
                "When the adjacency most recently entered the state 'up',
                 measured in hundredths of a second since the last
                 re-initialization of the network management subsystem.
                 Holds 0 if the adjacency has never been in state 'up'."
        ::= { isisISAdjEntry 11 }

    -- The IS Adjacency Area Address Table

    -- The IS Adjacency Area Address Table contains the set of
    -- Area Addresses of neighboring
    -- Intermediate Systems as reported in IIH PDUs.

        isisISAdjAreaAddrTable OBJECT-TYPE
            SYNTAX SEQUENCE OF IsisISAdjAreaAddrEntry
            MAX-ACCESS not-accessible
            STATUS current
            DESCRIPTION
                "This table contains the set of Area Addresses of
                 neighboring Intermediate Systems as reported in received
                 IIH PDUs."
            REFERENCE "{ISIS.aoi areaAddressesOfNeighbour (84)}"
        ::= { isisISAdj 2 }

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        isisISAdjAreaAddrEntry OBJECT-TYPE
            SYNTAX IsisISAdjAreaAddrEntry
            MAX-ACCESS not-accessible
            STATUS current
            DESCRIPTION
                "Each entry contains one Area Address reported by a
                 neighboring Intermediate System in its IIH PDUs.

                 Dynamically learned rows do not survive an agent reboot."
            INDEX { isisCircIndex,
                    isisISAdjIndex,
                    isisISAdjAreaAddrIndex }
        ::= { isisISAdjAreaAddrTable 1 }

        IsisISAdjAreaAddrEntry ::=
            SEQUENCE {
                isisISAdjAreaAddrIndex
                    Unsigned32,
                isisISAdjAreaAddress
                    IsisOSINSAddress
                }

        isisISAdjAreaAddrIndex OBJECT-TYPE
            SYNTAX Unsigned32(1..4294967295)
            MAX-ACCESS not-accessible
            STATUS current
            DESCRIPTION
                "An index for the areas associated with one neighbor.
                 This provides a simple way to walk the table."
        ::= { isisISAdjAreaAddrEntry 1 }

        isisISAdjAreaAddress OBJECT-TYPE
            SYNTAX IsisOSINSAddress
            MAX-ACCESS read-only
            STATUS current
            DESCRIPTION
                "One Area Address as reported in IIH PDUs received from
                 the neighbor."
        ::= { isisISAdjAreaAddrEntry 2 }

    -- The IS Adjacency IP Address Table

    -- The IS Adjacency IP Address Table contains the
    -- set of IP Addresses of neighboring Intermediate Systems
    -- as reported in received IIH PDUs.

        isisISAdjIPAddrTable OBJECT-TYPE
            SYNTAX SEQUENCE OF IsisISAdjIPAddrEntry

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            MAX-ACCESS not-accessible
            STATUS current
            DESCRIPTION
                "This table contains the set of IP Addresses of
                 neighboring Intermediate Systems as reported in received
                 IIH PDUs."
        ::= { isisISAdj 3 }

        isisISAdjIPAddrEntry OBJECT-TYPE
            SYNTAX IsisISAdjIPAddrEntry
            MAX-ACCESS not-accessible
            STATUS current
            DESCRIPTION
                "Each entry contains one IP Address reported by a
                 neighboring Intermediate System in its IIH PDUs.

                 Dynamically learned rows do not survive an agent reboot."
            INDEX { isisCircIndex,
                    isisISAdjIndex,
                    isisISAdjIPAddrIndex
                    }
        ::= { isisISAdjIPAddrTable 1 }

        IsisISAdjIPAddrEntry ::=
            SEQUENCE {
                isisISAdjIPAddrIndex
                    Unsigned32,
                isisISAdjIPAddrType
                     InetAddressType,
                isisISAdjIPAddrAddress
                    InetAddress
            }

        isisISAdjIPAddrIndex OBJECT-TYPE
            SYNTAX Unsigned32(1..4294967295)
            MAX-ACCESS not-accessible
            STATUS current
            DESCRIPTION
                "An index to this table that identifies the IP addresses
                 to which this entry belongs."
        ::= { isisISAdjIPAddrEntry 1 }

        isisISAdjIPAddrType OBJECT-TYPE
            SYNTAX InetAddressType
            MAX-ACCESS read-only
            STATUS current
            DESCRIPTION
                "The type of one IP Address as reported in IIH PDUs

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                 received from the neighbor."
        ::= { isisISAdjIPAddrEntry 2 }

        isisISAdjIPAddrAddress OBJECT-TYPE
            SYNTAX InetAddress
            MAX-ACCESS read-only
            STATUS current
            DESCRIPTION
                "One IP Address as reported in IIH PDUs received from the
                 neighbor.

                 The type of this address is determined by the value of
                 the isisISAdjIPAddrType object."
        ::= { isisISAdjIPAddrEntry 3 }

    -- The IS Adjacency Protocol Supported Table
    --
    -- The IS Adjacency Protocol Supported Table contains the set of
    -- protocols supported by neighboring
    -- Intermediate Systems as reported in received IIH PDUs.

        isisISAdjProtSuppTable OBJECT-TYPE
            SYNTAX SEQUENCE OF IsisISAdjProtSuppEntry
            MAX-ACCESS not-accessible
            STATUS current
            DESCRIPTION
                "This table contains the set of protocols supported by
                 neighboring Intermediate Systems as reported in received
                 IIH PDUs."
        ::= { isisISAdj 4 }

        isisISAdjProtSuppEntry OBJECT-TYPE
            SYNTAX IsisISAdjProtSuppEntry
            MAX-ACCESS not-accessible
            STATUS current
            DESCRIPTION
                "Each entry contains one protocol supported by a
                 neighboring Intermediate System as reported in its IIH
                 PDUs.

                 Dynamically learned rows do not survive an agent reboot."
            INDEX {  isisCircIndex,
                     isisISAdjIndex,
                     isisISAdjProtSuppProtocol }
        ::= { isisISAdjProtSuppTable 1 }

        IsisISAdjProtSuppEntry ::=
            SEQUENCE {

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                isisISAdjProtSuppProtocol
                    IsisSupportedProtocol
            }

        isisISAdjProtSuppProtocol OBJECT-TYPE
            SYNTAX IsisSupportedProtocol
            MAX-ACCESS read-only
            STATUS current
            DESCRIPTION
                "One supported protocol as reported in IIH PDUs received
                 from the neighbor."
        ::= { isisISAdjProtSuppEntry 1 }

    -- The Reachable Address Group
    --
    -- The Reachable Address Table
    -- Each entry records information about a reachable address
    -- (NSAP or address prefix) manually configured on the system
    -- or learned through another protocol.

        isisRATable OBJECT-TYPE
            SYNTAX SEQUENCE OF IsisRAEntry
            MAX-ACCESS not-accessible
            STATUS current
            DESCRIPTION
                "The table of Reachable Addresses to NSAPs or Address
                 Prefixes."
        ::= { isisReachAddr 1 }

        isisRAEntry OBJECT-TYPE
            SYNTAX IsisRAEntry
            MAX-ACCESS not-accessible
            STATUS current
            DESCRIPTION
                "Each entry defines a configured Reachable Address
                 to an NSAP or Address Prefix.

                 Dynamically created rows MUST survive an agent reboot."
            INDEX { isisCircIndex,
                    isisRAIndex }
        ::= { isisRATable 1 }

        IsisRAEntry ::=
            SEQUENCE {
                isisRAIndex
                    Unsigned32,
                isisRAExistState
                    RowStatus,

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                isisRAAdminState
                    IsisAdminState,
                isisRAAddrPrefix
                    IsisOSINSAddress,
                isisRAMapType
                    INTEGER,
                isisRAMetric
                    IsisDefaultMetric,
                isisRAMetricType
                    IsisMetricType,
                isisRASNPAAddress
                    IsisOSINSAddress,
                isisRASNPAMask
                    IsisOSINSAddress,
                isisRASNPAPrefix
                    IsisOSINSAddress,
                isisRAType
                    INTEGER
            }

        isisRAIndex OBJECT-TYPE
            SYNTAX Unsigned32(1..4294967295)
            MAX-ACCESS not-accessible
            STATUS current
            DESCRIPTION
                "The identifier for this isisRAEntry.  This value must be
                 unique amongst all Reachable Addresses on the same parent
                 Circuit."
        ::= { isisRAEntry 1 }

        isisRAExistState OBJECT-TYPE
            SYNTAX RowStatus
            MAX-ACCESS read-create
            STATUS current
            DESCRIPTION
                "The existence state of this Reachable Address.  This
                 object follows the ManualOrAutomatic behaviors.  Support
                 for 'createAndWait' and 'notInService' is not required.

                 A row entry cannot be modified when the value of this
                 object is 'active'."
        ::= { isisRAEntry 2 }

        isisRAAdminState OBJECT-TYPE
            SYNTAX IsisAdminState
            MAX-ACCESS read-create
            STATUS current
            DESCRIPTION

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                "The administrative state of the Reachable Address.  This
                 object follows the ManualOrAutomatic behaviors."
            DEFVAL { off }
        ::= { isisRAEntry 3 }

        isisRAAddrPrefix OBJECT-TYPE
            SYNTAX IsisOSINSAddress
            MAX-ACCESS read-create
            STATUS current
            DESCRIPTION
                "The destination of this Reachable Address.  This is an
                 Address Prefix.  This object follows the
                 ReplaceOnlyWhileDisabled and ManualOrAutomatic
                 behaviors."
            REFERENCE "{ISIS.aoi addressPrefix (98)}"
        ::= { isisRAEntry 4 }

        isisRAMapType OBJECT-TYPE
            SYNTAX INTEGER
                {
                    none (1),
                    explicit (2),
                    extractIDI (3),
                    extractDSP (4)
                }
            MAX-ACCESS read-create
            STATUS current
            DESCRIPTION
                "The type of mapping to be employed to ascertain the SNPA
                 Address that should be used in forwarding PDUs for this
                 Reachable Address prefix.  This object follows the
                 ManualOrAutomatic behavior.  The following values of
                 mapping type are defined:

                     none: The mapping is null because the neighbor SNPA is
                           implicit by nature of the subnetwork (e.g., a
                           point-to-point linkage).

                     explicit: The subnetwork addresses in the object
                           isisRASNPAAddress are to be used.

                     extractIDI: The SNPA is embedded in the IDI of
                           the destination NSAP Address.  The mapping
                           algorithm extracts the SNPA to be used
                           according to the format and encoding rules of
                           ISO8473/Add2.  This SNPA extraction algorithm can
                           be used in conjunction with Reachable Address
                           prefixes from the X.121, F.69, E.163, and E.164

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                           addressing subdomains.

                     extractDSP: All, or a suffix, of the SNPA is embedded
                           in the DSP of the destination address.  This SNPA
                           extraction algorithm extracts the embedded
                           subnetwork addressing information by performing a
                           logical AND of the isisRASNPAMask object value
                           with the destination address.  The part of the
                           SNPA extracted from the destination NSAP is
                           appended to the isisRASNPAPrefix object value to
                           form the next hop subnetwork addressing
                           information."

            REFERENCE "{ISO10589-ISIS.aoi mappingType (107)}"
        ::= { isisRAEntry 5 }

        isisRAMetric OBJECT-TYPE
            SYNTAX IsisDefaultMetric
            MAX-ACCESS read-create
            STATUS current
            DESCRIPTION
                "The metric value for reaching the specified
                 prefix over this circuit.  This object follows the
                 ManualOrAutomatic behavior."
            REFERENCE "{ISIS.aoi DefaultMetric (99)}"
            DEFVAL { 20 }
        ::= { isisRAEntry 6 }

        isisRAMetricType OBJECT-TYPE
            SYNTAX IsisMetricType
            MAX-ACCESS read-create
            STATUS current
            DESCRIPTION
                "Indicates whether the metric is internal or
                 external.  This object follows the ManualOrAutomatic
                 behavior."
            REFERENCE "{ISIS.aoi DefaultMetricType (103)}"
            DEFVAL { internal }
        ::= { isisRAEntry 7 }

        isisRASNPAAddress OBJECT-TYPE
            SYNTAX IsisOSINSAddress
            MAX-ACCESS read-create
            STATUS current
            DESCRIPTION
                "The SNPA Address to which a PDU may be forwarded in
                 order to reach a destination that matches the address
                 prefix of the Reachable Address.  This object follows the

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                 ManualOrAutomatic behavior."
            REFERENCE "{ISIS.aoi sNPAAddresses (109)}"
    -- Note only one address may be specified per Reachable Address
    -- in the MIB
            DEFVAL { ''H }
        ::= { isisRAEntry 8 }

        isisRASNPAMask OBJECT-TYPE
            SYNTAX IsisOSINSAddress
            MAX-ACCESS read-create
            STATUS current
            DESCRIPTION
                "A bit mask with 1 bit indicating the positions in the
                 effective destination address from which embedded SNPA
                 information is to be extracted.  For the extraction, the
                 first octet of the isisRASNPAMask object value is aligned
                 with the first octet (AFI) of the NSAP Address.  If the
                 isisRASNPAMask object value and NSAP Address are of
                 different lengths, the shorter of the two is logically
                 padded with zeros before performing the extraction.  This
                 object follows the ManualOrAutomatic behavior."
            REFERENCE "{ISIS.aoi sNPAMask (122)}"
            DEFVAL { '00'H }
        ::= { isisRAEntry 9 }

        isisRASNPAPrefix OBJECT-TYPE
            SYNTAX IsisOSINSAddress
            MAX-ACCESS read-create
            STATUS current
            DESCRIPTION
                "A fixed SNPA prefix for use when the isisRAMapType is
                 extractDSP.  The SNPA Address to use is formed by
                 concatenating the fixed SNPA prefix with a variable SNPA
                 part that is extracted from the effective destination
                 address.  For Reachable Address prefixes in which the
                 entire SNPA is embedded in the DSP, the SNPA Prefix shall
                 be null.  This object follows the ManualOrAutomatic
                 behavior."
            REFERENCE "{ISIS.aoi sNPAPrefix (123)}"
            DEFVAL { '00'H }
        ::= { isisRAEntry 10 }

        isisRAType OBJECT-TYPE
            SYNTAX INTEGER
                {
                    manual (1),
                    automatic (2)
                }

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            MAX-ACCESS read-create
            STATUS current
            DESCRIPTION
                "The type of Reachable address.  Those of type
                 manual are created by the network manager.  Those
                 of type automatic are created through propagation
                 of routing information from another routing
                 protocol (e.g., IDRP). "
            DEFVAL {manual}
        ::= {isisRAEntry 11 }

    -- The IP Reachable Address Table

    -- Each entry records information about one IP reachable
    -- address manually configured on this system or learned from
    -- another protocol.

        isisIPRATable OBJECT-TYPE
            SYNTAX SEQUENCE OF IsisIPRAEntry
            MAX-ACCESS not-accessible
            STATUS current
            DESCRIPTION
                "The table of IP Reachable Addresses to networks,
                 subnetworks, or hosts either manually configured or
                 learned from another protocol."
        ::= { isisIPReachAddr 1 }

        isisIPRAEntry OBJECT-TYPE
            SYNTAX IsisIPRAEntry
            MAX-ACCESS not-accessible
            STATUS current
            DESCRIPTION
                "Each entry defines an IP Reachable Address to a network,
                 subnetwork, or host.

                 Each IP Reachable Address may have multiple entries in the
                 table, one for each equal cost path to the reachable
                 address.

                 Dynamically created rows MUST survive an agent reboot.

                 Implementers need to be aware that if the total number
                 of elements (octets or sub-identifiers) in
                 isisIPRADestr, isisIPRADestPrefixLen, and
                 isisIPRANextHopIndex is too great, then OIDs of column
                 instances in this table will have more than 128
                 subidentifiers and cannot be accessed using SNMPv1,

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                 SNMPv2c, or SNMPv3."
            INDEX {  isisSysLevelIndex,
                     isisIPRADestType,
                     isisIPRADest,
                     isisIPRADestPrefixLen,
                     isisIPRANextHopIndex }
        ::= { isisIPRATable 1 }

        IsisIPRAEntry ::=
            SEQUENCE {
                isisIPRADestType
                    InetAddressType,
                isisIPRADest
                    InetAddress,
                isisIPRADestPrefixLen
                    InetAddressPrefixLength,
                isisIPRANextHopIndex
                    Unsigned32,
                isisIPRANextHopType
                    InetAddressType,
                isisIPRANextHop
                    InetAddress,
                isisIPRAType
                    INTEGER,
                isisIPRAExistState
                    RowStatus,
                isisIPRAAdminState
                    IsisAdminState,
                isisIPRAMetric
                    IsisDefaultMetric,
                isisIPRAMetricType
                    IsisMetricType,
                isisIPRAFullMetric
                    IsisFullMetric,
                isisIPRASNPAAddress
                    IsisOSINSAddress,
                isisIPRASourceType
                    INTEGER
            }

        isisIPRADestType OBJECT-TYPE
            SYNTAX InetAddressType
            MAX-ACCESS not-accessible
            STATUS current
            DESCRIPTION
                "The type of this IP Reachable Address."
        ::= { isisIPRAEntry 1 }

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        isisIPRADest OBJECT-TYPE
            SYNTAX InetAddress
            MAX-ACCESS not-accessible
            STATUS current
            DESCRIPTION
                "The destination of this IP Reachable Address.  This is
                 a network address, subnetwork address, or host
                 address.

                 The type of this address is determined by the value of
                 the isisIPRADestType object."

        ::= { isisIPRAEntry 2 }

        isisIPRADestPrefixLen OBJECT-TYPE
            SYNTAX InetAddressPrefixLength
            MAX-ACCESS not-accessible
            STATUS current
            DESCRIPTION
                "The length of the IP Netmask for Reachability Address.

                 The values for the index objects isisIPRADest and
                 isisIPRADestPrefixLen must be consistent.  When the value
                 of isisIPRADest (excluding the zone index, if one
                 is present) is x, then the bitwise logical-AND
                 of x with the value of the mask formed from the
                 corresponding index object isisIPRADestPrefixLen MUST be
                 equal to x.  If not, then the index pair is not
                 consistent, and an inconsistentName error must be
                 returned on SET or CREATE requests."
        ::= { isisIPRAEntry 3 }

        isisIPRANextHopIndex OBJECT-TYPE
            SYNTAX Unsigned32(1..4294967295)
            MAX-ACCESS not-accessible
            STATUS current
            DESCRIPTION
                "Index of next hop.  Used when there are multiple Equal
                 Cost Multipath alternatives for the same destination."
        ::= { isisIPRAEntry 4 }

        isisIPRANextHopType OBJECT-TYPE
            SYNTAX InetAddressType
            MAX-ACCESS read-create
            STATUS current
            DESCRIPTION
                "The type of the IP next hop address."
        ::= { isisIPRAEntry 5 }

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        isisIPRANextHop OBJECT-TYPE
            SYNTAX InetAddress
            MAX-ACCESS read-create
            STATUS current
            DESCRIPTION
                "The IP next hop to this destination.

                 The type of this address is determined by the value of
                 the isisIPRANextHopType object."
        ::= { isisIPRAEntry 6 }

        isisIPRAType OBJECT-TYPE
            SYNTAX INTEGER
                {
                    manual (1),
                    automatic (2)
                }
            MAX-ACCESS read-create
            STATUS current
            DESCRIPTION
                "The type of this IP Reachable Address.  Those of type
                 manual are created by the network manager.  Those of type
                 automatic are created through propagation of routing
                 information from another routing protocol.  This object
                 follows the ManualOrAutomatic behavior."
        ::= { isisIPRAEntry 7 }

        isisIPRAExistState OBJECT-TYPE
            SYNTAX RowStatus
            MAX-ACCESS read-create
            STATUS current
            DESCRIPTION
                "The state of this IP Reachable Address.  This object
                 follows the ExistenceState and ManualOrAutomatic
                 behaviors.  Support for 'createAndWait' and
                 'notInService' is not required.

                 A row entry cannot be modified when the value of this
                 object is 'active'."
        ::= { isisIPRAEntry 8 }

        isisIPRAAdminState OBJECT-TYPE
            SYNTAX IsisAdminState
            MAX-ACCESS read-create
            STATUS current
            DESCRIPTION
                "The administrative state of the IP Reachable Address.  This
                 object follows the IsisAdminState and ManualOrAutomatic

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                 behaviors."
            DEFVAL { off }
        ::= { isisIPRAEntry 9 }

        isisIPRAMetric OBJECT-TYPE
            SYNTAX IsisDefaultMetric
            MAX-ACCESS read-create
            STATUS current
            DESCRIPTION
                "The metric value for reaching the specified
                 destination over this circuit.  This object follows the
                 ManualOrAutomatic behavior."
            DEFVAL { 10 }
        ::= { isisIPRAEntry 10 }

        isisIPRAMetricType OBJECT-TYPE
            SYNTAX IsisMetricType
            MAX-ACCESS read-create
            STATUS current
            DESCRIPTION
                "Indicates whether the metric is internal or
                 external.  This object follows the ManualOrAutomatic
                 behavior."
            DEFVAL { internal }
        ::= { isisIPRAEntry 11 }

        isisIPRAFullMetric OBJECT-TYPE
            SYNTAX IsisFullMetric
            MAX-ACCESS read-create
            STATUS current
            DESCRIPTION
                "The wide metric value for reaching the specified
                 destination over this circuit.  This object follows the
                 ManualOrAutomatic behavior."
            DEFVAL { 10 }
        ::= { isisIPRAEntry 12 }

        isisIPRASNPAAddress OBJECT-TYPE
            SYNTAX IsisOSINSAddress
            MAX-ACCESS read-create
            STATUS current
            DESCRIPTION
                "The SNPA Address to which a PDU may be forwarded in
                 order to reach a destination that matches this IP
                 Reachable Address.  This object follows the
                 ManualOrAutomatic behavior."
            DEFVAL { ''H }
        ::= { isisIPRAEntry 13 }

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        isisIPRASourceType OBJECT-TYPE
            SYNTAX INTEGER
                {
                    static (1),
                    direct (2),
                    ospfv2 (3),
                    ospfv3 (4),
                    isis   (5),
                    rip    (6),
                    igrp   (7),
                    eigrp  (8),
                    bgp    (9),
                    other (10)
                }
            MAX-ACCESS read-only
            STATUS current
            DESCRIPTION
                "The origin of this route."
        ::= { isisIPRAEntry 14 }

    -- The LSP Database Table
    --
    -- The first table provides Summary Information about LSPs
    -- The next table provides a complete record

        isisLSPSummaryTable OBJECT-TYPE
            SYNTAX SEQUENCE OF IsisLSPSummaryEntry
            MAX-ACCESS not-accessible
            STATUS current
            DESCRIPTION
                "The table of LSP Headers."
        ::= { isisLSPDataBase 1 }

        isisLSPSummaryEntry OBJECT-TYPE
            SYNTAX IsisLSPSummaryEntry
            MAX-ACCESS not-accessible
            STATUS current
            DESCRIPTION
                "Each entry provides a summary describing an
                 LSP currently stored in the system.

                 Dynamically learned rows will not survive an
                 agent reboot."
            INDEX {  isisLSPLevel,
                     isisLSPID }
        ::= { isisLSPSummaryTable 1 }

        IsisLSPSummaryEntry ::=

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            SEQUENCE {
                isisLSPLevel
                    IsisISLevel,
                isisLSPID
                    IsisLinkStatePDUID,
                isisLSPSeq
                    Unsigned32,
                isisLSPZeroLife
                    TruthValue,
                isisLSPChecksum
                    IsisUnsigned16TC,
                isisLSPLifetimeRemain
                    IsisUnsigned16TC,
                isisLSPPDULength
                    IsisUnsigned16TC,
                isisLSPAttributes
                    IsisUnsigned8TC
            }

        isisLSPLevel OBJECT-TYPE
            SYNTAX IsisISLevel
            MAX-ACCESS not-accessible
            STATUS current
            DESCRIPTION
                "At which level does this LSP appear?"
        ::= { isisLSPSummaryEntry 1 }

        isisLSPID OBJECT-TYPE
            SYNTAX IsisLinkStatePDUID
            MAX-ACCESS not-accessible
            STATUS current
            DESCRIPTION
                "The 8-byte LSP ID for this Link State PDU."
        ::= { isisLSPSummaryEntry 2 }

        isisLSPSeq OBJECT-TYPE
            SYNTAX Unsigned32
            MAX-ACCESS read-only
            STATUS current
            DESCRIPTION
                "The sequence number for this LSP."
        ::= { isisLSPSummaryEntry 3 }

        isisLSPZeroLife OBJECT-TYPE
            SYNTAX TruthValue
            MAX-ACCESS read-only
            STATUS current
            DESCRIPTION

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                "Is this LSP being purged by this system?"
        ::= { isisLSPSummaryEntry 4 }

        isisLSPChecksum OBJECT-TYPE
            SYNTAX IsisUnsigned16TC
            MAX-ACCESS read-only
            STATUS current
            DESCRIPTION
                "The 16-bit Fletcher Checksum for this LSP."
        ::= { isisLSPSummaryEntry 5 }

        isisLSPLifetimeRemain OBJECT-TYPE
            SYNTAX IsisUnsigned16TC
            UNITS "seconds"
            MAX-ACCESS read-only
            STATUS current
            DESCRIPTION
                "The remaining lifetime, in seconds, for this LSP."
        ::= { isisLSPSummaryEntry 6 }

        isisLSPPDULength OBJECT-TYPE
            SYNTAX IsisUnsigned16TC
            MAX-ACCESS read-only
            STATUS current
            DESCRIPTION
                "The length of this LSP."
        ::= { isisLSPSummaryEntry 7 }

        isisLSPAttributes OBJECT-TYPE
            SYNTAX IsisUnsigned8TC
            MAX-ACCESS read-only
            STATUS current
            DESCRIPTION
                "Flags carried by the LSP."
        ::= { isisLSPSummaryEntry 8 }

    -- LSP Table
    --
    -- The full LSP as a sequence of {Type, Len, Value} tuples
    -- Since the underlying LSP may have changed while downloading
    -- TLVs, we provide the Sequence number and Checksum for each
    -- LSP TLV, so the network manager may verify that they are
    -- still working on the same version of the LSP.

        isisLSPTLVTable OBJECT-TYPE
            SYNTAX SEQUENCE OF IsisLSPTLVEntry
            MAX-ACCESS not-accessible
            STATUS current

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            DESCRIPTION
                "The table of LSPs in the database."
        ::= { isisLSPDataBase 2 }

        isisLSPTLVEntry OBJECT-TYPE
            SYNTAX IsisLSPTLVEntry
            MAX-ACCESS not-accessible
            STATUS current
            DESCRIPTION
                "Each entry describes a TLV within
                 an LSP currently stored in the system.

                 Dynamically learned rows will not survive an
                 agent reboot."
            INDEX {  isisLSPLevel,
                     isisLSPID,
                     isisLSPTLVIndex }
        ::= { isisLSPTLVTable 1 }

        IsisLSPTLVEntry ::=
            SEQUENCE {
                isisLSPTLVIndex
                    Unsigned32,
                isisLSPTLVSeq
                    Unsigned32,
                isisLSPTLVChecksum
                    IsisUnsigned16TC,
                isisLSPTLVType
                    IsisUnsigned8TC,
                isisLSPTLVLen
                    IsisUnsigned8TC,
                isisLSPTLVValue
                    OCTET STRING
            }

        isisLSPTLVIndex OBJECT-TYPE
            SYNTAX Unsigned32(1..4294967295)
            MAX-ACCESS not-accessible
            STATUS current
            DESCRIPTION
                "The index of this TLV in the LSP.  The first TLV has
                 index 1, and the Nth TLV has an index of N."
        ::= { isisLSPTLVEntry 1 }

        isisLSPTLVSeq OBJECT-TYPE
            SYNTAX Unsigned32
            MAX-ACCESS read-only
            STATUS current

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            DESCRIPTION
                "The sequence number for this LSP."
        ::= { isisLSPTLVEntry 2 }

        isisLSPTLVChecksum OBJECT-TYPE
            SYNTAX IsisUnsigned16TC
            MAX-ACCESS read-only
            STATUS current
            DESCRIPTION
                "The 16-bit Fletcher Checksum for this LSP."
        ::= { isisLSPTLVEntry 3 }

        isisLSPTLVType OBJECT-TYPE
            SYNTAX IsisUnsigned8TC
            MAX-ACCESS read-only
            STATUS current
            DESCRIPTION
                "The type of this TLV."
        ::= { isisLSPTLVEntry 4 }

        isisLSPTLVLen OBJECT-TYPE
            SYNTAX IsisUnsigned8TC
            MAX-ACCESS read-only
            STATUS current
            DESCRIPTION
                "The length of this TLV."
        ::= { isisLSPTLVEntry 5 }

        isisLSPTLVValue OBJECT-TYPE
            SYNTAX OCTET STRING (SIZE(0..255))
            MAX-ACCESS read-only
            STATUS current
            DESCRIPTION
                "The value of this TLV."
        ::= { isisLSPTLVEntry 6 }

    -- The IS-IS Notification Table

    -- The IS-IS Notification Table records fields that are
    -- required for notifications

        isisNotificationEntry OBJECT IDENTIFIER
            ::= { isisNotification 1 }

        isisNotificationSysLevelIndex OBJECT-TYPE
            SYNTAX IsisLevel
            MAX-ACCESS accessible-for-notify

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            STATUS current
            DESCRIPTION
                "The system level for this notification."
        ::= { isisNotificationEntry 1 }

        isisNotificationCircIfIndex OBJECT-TYPE
            SYNTAX Unsigned32 (1..2147483647)
            MAX-ACCESS accessible-for-notify
            STATUS current
            DESCRIPTION
                "The identifier of this circuit relevant to
                 this notification."
        ::= { isisNotificationEntry 2 }

        isisPduLspId OBJECT-TYPE
            SYNTAX IsisLinkStatePDUID
            MAX-ACCESS accessible-for-notify
            STATUS current
            DESCRIPTION
                "An Octet String that uniquely identifies
                 a Link State PDU."
        ::= { isisNotificationEntry 3 }

        isisPduFragment OBJECT-TYPE
            SYNTAX IsisPDUHeader
            MAX-ACCESS accessible-for-notify
            STATUS current
            DESCRIPTION
                "Holds up to 64 initial bytes of a PDU that
                 triggered the notification."
        ::= { isisNotificationEntry 4 }

        isisPduFieldLen OBJECT-TYPE
            SYNTAX IsisUnsigned8TC
            MAX-ACCESS accessible-for-notify
            STATUS current
            DESCRIPTION
                "Holds the System ID length reported in PDU we received."
        ::= { isisNotificationEntry 5 }

        isisPduMaxAreaAddress OBJECT-TYPE
            SYNTAX IsisUnsigned8TC
            MAX-ACCESS accessible-for-notify
            STATUS current
            DESCRIPTION
                "Holds the Max Area Addresses reported in a PDU
                 we received."
        ::= { isisNotificationEntry 6 }

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        isisPduProtocolVersion OBJECT-TYPE
            SYNTAX IsisUnsigned8TC
            MAX-ACCESS accessible-for-notify
            STATUS current
            DESCRIPTION
                "Holds the Protocol version reported in PDU we received."
        ::= { isisNotificationEntry 7 }

        isisPduLspSize OBJECT-TYPE
            SYNTAX Unsigned32 (0..2147483647)
            MAX-ACCESS accessible-for-notify
            STATUS current
            DESCRIPTION
                "Holds the size of LSP we received that is too
                 big to forward."
        ::= { isisNotificationEntry 8 }

        isisPduOriginatingBufferSize OBJECT-TYPE
            SYNTAX IsisUnsigned16TC (0..16000)
            MAX-ACCESS accessible-for-notify
            STATUS current
            DESCRIPTION
                "Holds the size of isisSysLevelOrigLSPBuffSize advertised
                 by the peer in the originatingLSPBufferSize TLV.
                 If the peer does not advertise this TLV, this
                 value is set to 0."
        ::= { isisNotificationEntry 9 }

        isisPduBufferSize OBJECT-TYPE
            SYNTAX IsisUnsigned16TC (0..16000)
            MAX-ACCESS accessible-for-notify
            STATUS current
            DESCRIPTION
                "Holds the size of LSP received from peer."
        ::= { isisNotificationEntry 10 }

        isisPduProtocolsSupported OBJECT-TYPE
            SYNTAX OCTET STRING (SIZE(0..255))
            MAX-ACCESS accessible-for-notify
            STATUS current
            DESCRIPTION
                "The list of protocols supported by an
                 adjacent system.  This may be empty."
        ::= { isisNotificationEntry 11 }

        isisAdjState OBJECT-TYPE
            SYNTAX INTEGER
                {

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                     down (1),
                     initializing (2),
                     up (3),
                     failed(4)
                }
            MAX-ACCESS accessible-for-notify
            STATUS current
            DESCRIPTION
                "The current state of an adjacency."
        ::= { isisNotificationEntry 12 }

        isisErrorOffset OBJECT-TYPE
            SYNTAX Unsigned32
            MAX-ACCESS accessible-for-notify
            STATUS current
            DESCRIPTION
                "An offset to a problem in a PDU.  If the problem
                 is a malformed TLV, this points to the beginning
                 of the TLV.  If the problem is in the header, this
                 points to the byte that is suspicious."
        ::= { isisNotificationEntry 13 }

        isisErrorTLVType OBJECT-TYPE
            SYNTAX Unsigned32 (0..255)
            MAX-ACCESS accessible-for-notify
            STATUS current
            DESCRIPTION
                 "The type for a malformed TLV."
        ::= { isisNotificationEntry 14 }

        isisNotificationAreaAddress OBJECT-TYPE
            SYNTAX IsisOSINSAddress
            MAX-ACCESS accessible-for-notify
            STATUS current
            DESCRIPTION
                "An Area Address."
        ::= { isisNotificationEntry 15 }

    -- Notification definitions
    --
    -- Note that notifications can be disabled by setting
    --     isisSysNotificationEnable false

        isisDatabaseOverload NOTIFICATION-TYPE
            OBJECTS {
                isisNotificationSysLevelIndex,
                isisSysLevelState
            }

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            STATUS current
            DESCRIPTION
                "This notification is generated when the system
                 enters or leaves the Overload state.  The number
                 of times this has been generated and cleared is kept
                 track of by isisSysStatLSPDbaseOloads."
        ::= { isisNotifications 1 }

        isisManualAddressDrops NOTIFICATION-TYPE
            OBJECTS {
                isisNotificationAreaAddress
            }
            STATUS current
            DESCRIPTION
                "This notification is generated when one of the
                 manual areaAddresses assigned to this system is
                 ignored when computing routes.  The object
                 isisNotificationAreaAddress describes the area that
                 has been dropped.

                 The number of times this event has been generated
                 is counted by isisSysStatManAddrDropFromAreas.

                 The agent must throttle the generation of
                 consecutive isisManualAddressDrops notifications
                 so that there is at least a 5-second gap between
                 notifications of this type.  When notifications
                 are throttled, they are dropped, not queued for
                 sending at a future time."
        ::= { isisNotifications 2 }

        isisCorruptedLSPDetected NOTIFICATION-TYPE
            OBJECTS {
                isisNotificationSysLevelIndex,
                isisPduLspId
            }
            STATUS current
            DESCRIPTION
                "This notification is generated when we find that
                 an LSP that was stored in memory has become
                 corrupted.  The number of times this has been
                 generated is counted by isisSysCorrLSPs.

                 We forward an LSP ID.  We may have independent
                 knowledge of the ID, but in some implementations
                 there is a chance that the ID itself will be
                 corrupted."

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        ::= { isisNotifications 3 }

        isisAttemptToExceedMaxSequence NOTIFICATION-TYPE
            OBJECTS {
                isisNotificationSysLevelIndex,
                isisPduLspId
            }
            STATUS current
            DESCRIPTION
                "When the sequence number on an LSP we generate
                 wraps the 32-bit sequence counter, we purge and
                 wait to re-announce this information.  This
                 notification describes that event.  Since these
                 should not be generated rapidly, we generate
                 an event each time this happens.

                 While the first 6 bytes of the LSPID are ours,
                 the other two contain useful information."

        ::= { isisNotifications 4 }

        isisIDLenMismatch  NOTIFICATION-TYPE
            OBJECTS {
                isisNotificationSysLevelIndex,
                isisPduFieldLen,
                isisNotificationCircIfIndex,
                isisPduFragment
            }
            STATUS current
            DESCRIPTION
                "A notification sent when we receive a PDU
                 with a different value for the System ID Length.
                 This notification includes an index to identify
                 the circuit where we saw the PDU and the header of
                 the PDU, which may help a network manager identify
                 the source of the confusion.

                 The agent must throttle the generation of
                 consecutive isisIDLenMismatch notifications
                 so that there is at least a 5-second gap between
                 notifications of this type.  When notifications
                 are throttled, they are dropped, not queued for
                 sending at a future time."

        ::= { isisNotifications 5 }

        isisMaxAreaAddressesMismatch NOTIFICATION-TYPE
            OBJECTS {

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                isisNotificationSysLevelIndex,
                isisPduMaxAreaAddress,
                isisNotificationCircIfIndex,
                isisPduFragment
            }

            STATUS current
            DESCRIPTION
                "A notification sent when we receive a PDU
                 with a different value for the Maximum Area
                 Addresses.  This notification includes the
                 header of the packet, which may help a
                 network manager identify the source of the
                 confusion.

                 The agent must throttle the generation of
                 consecutive isisMaxAreaAddressesMismatch
                 notifications so that there is at least a 5-second
                 gap between notifications of this type.  When
                 notifications are throttled, they are dropped, not
                 queued for sending at a future time."

        ::= { isisNotifications 6 }

        isisOwnLSPPurge NOTIFICATION-TYPE
            OBJECTS {
                isisNotificationSysLevelIndex,
                isisNotificationCircIfIndex,
                isisPduLspId
            }
            STATUS current
            DESCRIPTION
                "A notification sent when we receive a PDU
                 with our systemID and zero age.  This
                 notification includes the circuit Index
                 and router ID from the LSP, if available,
                 which may help a network manager
                 identify the source of the confusion."

        ::= { isisNotifications 7 }

        isisSequenceNumberSkip NOTIFICATION-TYPE
            OBJECTS {
                isisNotificationSysLevelIndex,
                isisNotificationCircIfIndex,
                isisPduLspId
            }
            STATUS current

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            DESCRIPTION
                "When we receive an LSP with our System ID
                 and different contents, we may need to reissue
                 the LSP with a higher sequence number.

                 We send this notification if we need to increase
                 the sequence number by more than one.  If two
                 Intermediate Systems are configured with the same
                 System ID, this notification will fire."

        ::= { isisNotifications 8 }

        isisAuthenticationTypeFailure NOTIFICATION-TYPE
            OBJECTS {
                isisNotificationSysLevelIndex,
                isisNotificationCircIfIndex,
                isisPduFragment
            }
            STATUS current
            DESCRIPTION
                "A notification sent when we receive a PDU
                 with the wrong authentication type field.
                 This notification includes the header of the
                 packet, which may help a network manager
                 identify the source of the confusion.

                 The agent must throttle the generation of
                 consecutive isisAuthenticationTypeFailure
                 notifications so that there is at least a 5-second
                 gap between notifications of this type.  When
                 notifications are throttled, they are dropped, not
                 queued for sending at a future time."

        ::= { isisNotifications 9 }

        isisAuthenticationFailure NOTIFICATION-TYPE
            OBJECTS {
                isisNotificationSysLevelIndex,
                isisNotificationCircIfIndex,
                isisPduFragment
            }
            STATUS current
            DESCRIPTION
                "A notification sent when we receive a PDU
                 with an incorrect authentication information
                 field.  This notification includes the header
                 of the packet, which may help a network manager
                 identify the source of the confusion.

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                 The agent must throttle the generation of
                 consecutive isisAuthenticationFailure
                 notifications so that there is at least a 5-second
                 gap between notifications of this type.  When
                 notifications are throttled, they are dropped, not
                 queued for sending at a future time."

        ::= { isisNotifications 10 }

        isisVersionSkew NOTIFICATION-TYPE
            OBJECTS {
                isisNotificationSysLevelIndex,
                isisNotificationCircIfIndex,
                isisPduProtocolVersion,
                isisPduFragment
            }
            STATUS current
            DESCRIPTION
                "A notification sent when we receive a Hello
                 PDU from an IS running a different version
                 of the protocol.  This notification includes
                 the header of the packet, which may help a
                 network manager identify the source of the
                 confusion.

                 The agent must throttle the generation of
                 consecutive isisVersionSkew notifications
                 so that there is at least a 5-second gap
                 between notifications of this type.  When
                 notifications are throttled, they are dropped, not
                 queued for sending at a future time."

        ::= { isisNotifications 11 }

        isisAreaMismatch NOTIFICATION-TYPE
            OBJECTS {
                isisNotificationCircIfIndex,
                isisPduFragment
            }
            STATUS current
            DESCRIPTION
                "A notification sent when we receive a Hello
                 PDU from an IS that does not share any
                 area address.  This notification includes
                 the header of the packet, which may help a
                 network manager identify the source of the
                 confusion.

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                 The agent must throttle the generation of
                 consecutive isisAreaMismatch notifications
                 so that there is at least a 5-second gap
                 between notifications of this type.  When
                 notifications are throttled, they are dropped, not
                 queued for sending at a future time."

        ::= { isisNotifications 12 }

        isisRejectedAdjacency NOTIFICATION-TYPE
            OBJECTS {
                isisNotificationSysLevelIndex,
                isisNotificationCircIfIndex,
                isisPduFragment
            }
            STATUS current
            DESCRIPTION
                "A notification sent when we receive a Hello
                 PDU from an IS but do not establish an
                 adjacency for some reason.

                 The agent must throttle the generation of
                 consecutive isisRejectedAdjacency notifications
                 so that there is at least a 5-second gap
                 between notifications of this type.  When
                 notifications are throttled, they are dropped, not
                 queued for sending at a future time."

        ::= { isisNotifications 13 }

        isisLSPTooLargeToPropagate NOTIFICATION-TYPE
            OBJECTS {
                isisNotificationSysLevelIndex,
                isisNotificationCircIfIndex,
                isisPduLspSize,
                isisPduLspId
            }
            STATUS current
            DESCRIPTION
                "A notification sent when we attempt to propagate
                 an LSP that is larger than the dataLinkBlockSize
                 for the circuit.

                 The agent must throttle the generation of
                 consecutive isisLSPTooLargeToPropagate notifications
                 so that there is at least a 5-second gap
                 between notifications of this type.  When
                 notifications are throttled, they are dropped, not

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                 queued for sending at a future time."

        ::= { isisNotifications 14 }

        isisOrigLSPBuffSizeMismatch NOTIFICATION-TYPE
            OBJECTS {
                isisNotificationSysLevelIndex,
                isisNotificationCircIfIndex,
                isisPduLspId,
                isisPduOriginatingBufferSize,
                isisPduBufferSize
            }
            STATUS current
            DESCRIPTION
                "A notification sent when a Level 1 LSP or Level
                 2 LSP is received that is larger than the local
                 value for isisSysLevelOrigLSPBuffSize, or when an
                 LSP is received that contains the supported Buffer Size
                 option and the value in the PDU option field does
                 not match the local value for isisSysLevelOrigLSPBuffSize.
                 We pass up the size from the option field and the
                 size of the LSP when one of them exceeds our configuration.

                 The agent must throttle the generation of
                 consecutive isisOrigLSPBuffSizeMismatch notifications
                 so that there is at least a 5-second gap
                 between notifications of this type.  When
                 notifications are throttled, they are dropped, not
                 queued for sending at a future time."

        ::= { isisNotifications 15 }

        isisProtocolsSupportedMismatch NOTIFICATION-TYPE
            OBJECTS {
                isisNotificationSysLevelIndex,
                isisNotificationCircIfIndex,
                isisPduProtocolsSupported,
                isisPduLspId,
                isisPduFragment
            }
            STATUS current
            DESCRIPTION
                "A notification sent when a non-pseudonode
                 segment 0 LSP is received that has no matching
                 protocols supported.  This may be because the system
                 does not generate the field, or because there are no
                 common elements.  The list of protocols supported
                 should be included in the notification: it may be

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                 empty if the TLV is not supported, or if the
                 TLV is empty.

                 The agent must throttle the generation of
                 consecutive isisProtocolsSupportedMismatch
                 notifications so that there is at least a 5-second
                 gap between notifications of this type.  When
                 notifications are throttled, they are dropped, not
                 queued for sending at a future time."

        ::= { isisNotifications 16 }

        isisAdjacencyChange NOTIFICATION-TYPE
            OBJECTS {
                isisNotificationSysLevelIndex,
                isisNotificationCircIfIndex,
                isisPduLspId,
                isisAdjState
            }
            STATUS current
            DESCRIPTION
                "A notification sent when an adjacency changes
                 state, entering or leaving state up.
                 The first 6 bytes of the isisPduLspId are the
                 SystemID of the adjacent IS.
                 The isisAdjState is the new state of the adjacency."

        ::= { isisNotifications 17 }

        isisLSPErrorDetected NOTIFICATION-TYPE
            OBJECTS {
                isisNotificationSysLevelIndex,
                isisPduLspId,
                isisNotificationCircIfIndex,
                isisPduFragment,
                isisErrorOffset,
                isisErrorTLVType
            }
            STATUS current
            DESCRIPTION
                "This notification is generated when we receive
                 an LSP with a parse error.  The isisCircIfIndex
                 holds an index of the circuit on which the PDU
                 arrived.  The isisPduFragment holds the start of the
                 LSP, and the isisErrorOffset points to the problem.

                 If the problem is a malformed TLV, isisErrorOffset
                 points to the start of the TLV, and isisErrorTLVType

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                 holds the value of the type.

                 If the problem is with the LSP header, isisErrorOffset
                 points to the suspicious byte.

                 The number of such LSPs is accumulated in
                 isisSysStatLSPErrors."

        ::= { isisNotifications 18 }

    -- Agent Conformance Definitions
    -- We define the objects a conformant agent must define

    isisCompliances OBJECT IDENTIFIER ::= { isisConformance 1 }
    isisGroups      OBJECT IDENTIFIER ::= { isisConformance 2 }

    -- compliance statements

        isisCompliance MODULE-COMPLIANCE
            STATUS current
            DESCRIPTION
                "The compliance statement for agents that support
                 the IS-IS MIB.

                 There are a number of INDEX objects that cannot be
                 represented in the form of OBJECT clauses in SMIv2,
                 but for which there are compliance requirements.
                 Those requirements and similar requirements for
                 related objects are expressed below, in
                 pseudo-OBJECT clause form, in this description:

                 -- OBJECT isisSummAddressType
                 -- SYNTAX InetAddressType { ipv4(1), ipv6(2) }
                 --
                 -- DESCRIPTION
                 --    The MIB requires support for IPv4 Summary
                 --    Addresses and anticipates the support of
                 --    IPv6 addresses.
                 --
                 --
                 -- OBJECT isisRedistributeAddrType
                 -- SYNTAX InetAddressType { ipv4(1), ipv6(2) }
                 --
                 -- DESCRIPTION
                 --    The MIB requires support for IPv4
                 --    Redistribution Addresses and anticipates
                 --    the support of IPv6 addresses."
                 --

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                 --
                 -- OBJECT isisISAdjIPAddrType
                 -- SYNTAX InetAddressType { ipv4(1), ipv6(2) }
                 --
                 -- DESCRIPTION
                 --    The MIB requires support for IPv4
                 --    Adjacency Addresses and anticipates the
                 --    support of IPv6 addresses.
            MODULE -- this module
                MANDATORY-GROUPS {
                        isisSystemGroup,
                        isisCircuitGroup,
                        isisISAdjGroup,
                        isisNotificationObjectGroup,
                        isisNotificationGroup
                }
        ::= { isisCompliances 1 }

        -- List of all groups, mandatory and optional
        isisAdvancedCompliance MODULE-COMPLIANCE
            STATUS current
            DESCRIPTION
                "The compliance statement for agents that fully
                 support the IS-IS MIB.

                 There are a number of INDEX objects that cannot be
                 represented in the form of OBJECT clauses in SMIv2,
                 but for which there are compliance requirements.
                 Those requirements and similar requirements for
                 related objects are expressed below, in
                 pseudo-OBJECT clause form, in this description:

                 -- OBJECT isisSummAddressType
                 -- SYNTAX InetAddressType { ipv4(1), ipv6(2) }
                 --
                 -- DESCRIPTION
                 --    The MIB requires support for IPv4 Summary
                 --    Addresses and anticipates the support of
                 --    IPv6 addresses.
                 --
                 --
                 -- OBJECT isisRedistributeAddrType
                 -- SYNTAX InetAddressType { ipv4(1), ipv6(2) }
                 --
                 -- DESCRIPTION
                 --    The MIB requires support for IPv4
                 --    Redistribution Addresses and anticipates
                 --    the support of IPv6 addresses."

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                 --
                 --
                 -- OBJECT isisISAdjIPAddrType
                 -- SYNTAX InetAddressType { ipv4(1), ipv6(2) }
                 --
                 -- DESCRIPTION
                 --    The MIB requires support for IPv4
                 --    Adjacency Addresses and anticipates the
                 --    support of IPv6 addresses.
                 --
                 --
                 -- OBJECT isisIPRADestType
                 -- SYNTAX InetAddressType { ipv4(1), ipv6(2) }
                 --
                 -- DESCRIPTION
                 --    The MIB requires support for IPv4 RA
                 --    Addresses and anticipates the support of
                 --    IPv6 addresses.
                 --
                 --
                 -- OBJECT isisIPRANextHopType
                 -- SYNTAX InetAddressType { ipv4(1), ipv6(2) }
                 --
                 -- DESCRIPTION
                 --    The MIB requires support for IPv4 NextHop
                 --    Addresses and anticipates the support of
                 --    IPv6 addresses.
            MODULE -- this module
                MANDATORY-GROUPS {
                        isisSystemGroup,
                        isisCircuitGroup,
                        isisISAdjGroup,
                        isisNotificationObjectGroup,
                        isisNotificationGroup,
                        isisISPDUCounterGroup,
                        isisRATableGroup,
                        isisISIPRADestGroup,
                        isisLSPGroup
                }
        ::= { isisCompliances 2 }

        isisReadOnlyCompliance MODULE-COMPLIANCE
           STATUS     current
           DESCRIPTION
                   "When this MIB is implemented without support for
                    read-create (i.e., in read-only mode), the
                    implementation can claim read-only compliance.  Such
                    a device can then be monitored but cannot be

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                    configured with this MIB."
           MODULE -- this module
                MANDATORY-GROUPS {
                        isisSystemGroup,
                        isisCircuitGroup,
                        isisISAdjGroup
                }

           OBJECT isisSysLevelType
           MIN-ACCESS read-only
           DESCRIPTION
                "Write access is not required."

           OBJECT isisSysID
           MIN-ACCESS read-only
           DESCRIPTION
                "Write access is not required."

           OBJECT isisSysMaxPathSplits
           MIN-ACCESS read-only
           DESCRIPTION
                "Write access is not required."

           OBJECT isisSysMaxLSPGenInt
           MIN-ACCESS read-only
           DESCRIPTION
                "Write access is not required."

           OBJECT isisSysPollESHelloRate
           MIN-ACCESS read-only
           DESCRIPTION
                "Write access is not required."

           OBJECT isisSysWaitTime
           MIN-ACCESS read-only
           DESCRIPTION
                "Write access is not required."

           OBJECT isisSysAdminState
           MIN-ACCESS read-only
           DESCRIPTION
                "Write access is not required."

           OBJECT isisSysL2toL1Leaking
           MIN-ACCESS read-only
           DESCRIPTION
                "Write access is not required."

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           OBJECT isisSysMaxAge
           MIN-ACCESS read-only
           DESCRIPTION
                "Write access is not required."

           OBJECT isisManAreaAddrExistState
           MIN-ACCESS read-only
           DESCRIPTION
                "Write access is not required."

           OBJECT isisSysLevelOrigLSPBuffSize
           MIN-ACCESS read-only
           DESCRIPTION
                "Write access is not required."

           OBJECT isisSysLevelMinLSPGenInt
           MIN-ACCESS read-only
           DESCRIPTION
                "Write access is not required."

           OBJECT isisSysLevelSetOverload
           MIN-ACCESS read-only
           DESCRIPTION
                "Write access is not required."

           OBJECT isisSysLevelSetOverloadUntil
           MIN-ACCESS read-only
           DESCRIPTION
                "Write access is not required."

           OBJECT isisSysLevelMetricStyle
           MIN-ACCESS read-only
           DESCRIPTION
                "Write access is not required."

           OBJECT isisSysLevelSPFConsiders
           MIN-ACCESS read-only
           DESCRIPTION
                "Write access is not required."

           OBJECT isisSysLevelTEEnabled
           MIN-ACCESS read-only
           DESCRIPTION
                "Write access is not required."

           OBJECT isisSysReceiveLSPBufferSize
           MIN-ACCESS read-only
           DESCRIPTION

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                "Write access is not required."

           OBJECT isisSummAddrExistState
           MIN-ACCESS read-only
           DESCRIPTION
                "Write access is not required."

           OBJECT isisSummAddrMetric
           MIN-ACCESS read-only
           DESCRIPTION
                "Write access is not required."

           OBJECT isisSummAddrFullMetric
           MIN-ACCESS read-only
           DESCRIPTION
                "Write access is not required."

           OBJECT isisRedistributeAddrExistState
           MIN-ACCESS read-only
           DESCRIPTION
                "Write access is not required."

           OBJECT isisCircAdminState
           MIN-ACCESS read-only
           DESCRIPTION
                "Write access is not required."

           OBJECT isisCircExistState
           MIN-ACCESS read-only
           DESCRIPTION
                "Write access is not required."

           OBJECT isisCircType
           MIN-ACCESS read-only
           DESCRIPTION
                "Write access is not required."

           OBJECT isisCircExtDomain
           MIN-ACCESS read-only
           DESCRIPTION
                "Write access is not required."

           OBJECT isisCircLevelType
           MIN-ACCESS read-only
           DESCRIPTION
                "Write access is not required."

           OBJECT isisCircPassiveCircuit

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           MIN-ACCESS read-only
           DESCRIPTION
                "Write access is not required."

           OBJECT isisCircMeshGroupEnabled
           MIN-ACCESS read-only
           DESCRIPTION
                "Write access is not required."

           OBJECT isisCircMeshGroup
           MIN-ACCESS read-only
           DESCRIPTION
                "Write access is not required."

           OBJECT isisCircSmallHellos
           MIN-ACCESS read-only
           DESCRIPTION
                "Write access is not required."

           OBJECT isisCircExtendedCircID
           MIN-ACCESS read-only
           DESCRIPTION
                "Write access is not required."

           OBJECT isisCircIfIndex
           MIN-ACCESS read-only
           DESCRIPTION
                "Write access is not required."

           OBJECT isisCirc3WayEnabled
           MIN-ACCESS read-only
           DESCRIPTION
                "Write access is not required."

           OBJECT isisCircLevelMetric
           MIN-ACCESS read-only
           DESCRIPTION
                "Write access is not required."

           OBJECT isisCircLevelWideMetric
           MIN-ACCESS read-only
           DESCRIPTION
                "Write access is not required."

           OBJECT isisCircLevelISPriority
           MIN-ACCESS read-only
           DESCRIPTION
                "Write access is not required."

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           OBJECT isisCircLevelHelloMultiplier
           MIN-ACCESS read-only
           DESCRIPTION
                "Write access is not required."

           OBJECT isisCircLevelHelloTimer
           MIN-ACCESS read-only
           DESCRIPTION
                "Write access is not required."

           OBJECT isisCircLevelDRHelloTimer
           MIN-ACCESS read-only
           DESCRIPTION
                "Write access is not required."

           OBJECT isisCircLevelLSPThrottle
           MIN-ACCESS read-only
           DESCRIPTION
                "Write access is not required."

           OBJECT isisCircLevelMinLSPRetransInt
           MIN-ACCESS read-only
           DESCRIPTION
                "Write access is not required."

           OBJECT isisCircLevelCSNPInterval
           MIN-ACCESS read-only
           DESCRIPTION
                "Write access is not required."

           OBJECT isisCircLevelPartSNPInterval
           MIN-ACCESS read-only
           DESCRIPTION
                "Write access is not required."

        ::= { isisCompliances 3 }

    -- MIB Grouping

        isisSystemGroup OBJECT-GROUP
            OBJECTS {
                isisSysVersion,
                isisSysLevelType,
                isisSysID,
                isisSysMaxPathSplits,
                isisSysMaxLSPGenInt,
                isisSysPollESHelloRate,
                isisSysWaitTime,

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                isisSysAdminState,
                isisSysL2toL1Leaking,
                isisSysMaxAge,
                isisSysProtSupported,
                isisSysNotificationEnable,
                isisManAreaAddrExistState,
                isisSysLevelOrigLSPBuffSize,
                isisSysLevelMinLSPGenInt,
                isisSysLevelState,
                isisSysLevelSetOverload,
                isisSysLevelSetOverloadUntil,
                isisSysLevelMetricStyle,
                isisSysLevelSPFConsiders,
                isisSysLevelTEEnabled,
                isisSysReceiveLSPBufferSize,
                isisSummAddrExistState,
                isisSummAddrMetric,
                isisAreaAddr,
                isisSummAddrFullMetric,
                isisRedistributeAddrExistState,
                isisRouterHostName,
                isisRouterID,
                isisSysStatCorrLSPs,
                isisSysStatLSPDbaseOloads,
                isisSysStatManAddrDropFromAreas,
                isisSysStatAttmptToExMaxSeqNums,
                isisSysStatSeqNumSkips,
                isisSysStatOwnLSPPurges,
                isisSysStatIDFieldLenMismatches,
                isisSysStatPartChanges,
                isisSysStatSPFRuns,
                isisSysStatAuthTypeFails,
                isisSysStatAuthFails,
                isisSysStatLSPErrors
            }
            STATUS current
            DESCRIPTION
                "The collections of objects used to manage an
                 IS-IS router."
        ::= { isisGroups 1 }

        isisCircuitGroup OBJECT-GROUP
            OBJECTS {
                isisNextCircIndex,
                isisCircAdminState,
                isisCircExistState,
                isisCircType,
                isisCircExtDomain,

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                isisCircLevelType,
                isisCircAdjChanges,
                isisCircNumAdj,
                isisCircInitFails,
                isisCircRejAdjs,
                isisCircIDFieldLenMismatches,
                isisCircMaxAreaAddrMismatches,
                isisCircAuthTypeFails,
                isisCircAuthFails,
                isisCircLANDesISChanges,
                isisCircPassiveCircuit,
                isisCircMeshGroupEnabled,
                isisCircMeshGroup,
                isisCircSmallHellos,
                isisCircLastUpTime,
                isisCirc3WayEnabled,
                isisCircExtendedCircID,
                isisCircIfIndex,
                isisCircLevelMetric,
                isisCircLevelWideMetric,
                isisCircLevelISPriority,
                isisCircLevelIDOctet,
                isisCircLevelID,
                isisCircLevelDesIS,
                isisCircLevelHelloMultiplier,
                isisCircLevelHelloTimer,
                isisCircLevelDRHelloTimer,
                isisCircLevelLSPThrottle,
                isisCircLevelMinLSPRetransInt,
                isisCircLevelCSNPInterval,
                isisCircLevelPartSNPInterval
            }
            STATUS current
            DESCRIPTION
                "The collections of objects used to describe an
                 IS-IS Circuit."
        ::= { isisGroups 2 }

        isisISAdjGroup OBJECT-GROUP
            OBJECTS {
                isisISAdjState,
                isisISAdj3WayState,
                isisISAdjNeighSNPAAddress,
                isisISAdjNeighSysType,
                isisISAdjNeighSysID,
                isisISAdjNbrExtendedCircID,
                isisISAdjUsage,
                isisISAdjHoldTimer,

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                isisISAdjNeighPriority,
                isisISAdjLastUpTime,
                isisISAdjAreaAddress,
                isisISAdjIPAddrType,
                isisISAdjIPAddrAddress,
                isisISAdjProtSuppProtocol
            }
            STATUS current
            DESCRIPTION
                "The collections of objects used to manage an
                 IS-IS Adjacency."
        ::= { isisGroups 3 }

        isisNotificationObjectGroup OBJECT-GROUP
            OBJECTS {
                isisNotificationSysLevelIndex,
                isisNotificationCircIfIndex,
                isisPduLspId,
                isisPduFragment,
                isisPduFieldLen,
                isisPduMaxAreaAddress,
                isisPduProtocolVersion,
                isisPduLspSize,
                isisPduOriginatingBufferSize,
                isisPduBufferSize,
                isisPduProtocolsSupported,
                isisAdjState,
                isisErrorOffset,
                isisErrorTLVType,
                isisNotificationAreaAddress
            }
            STATUS current
            DESCRIPTION
                "The objects used to record notification parameters."
        ::= { isisGroups 4 }

        isisNotificationGroup        NOTIFICATION-GROUP
            NOTIFICATIONS {
                isisDatabaseOverload,
                isisManualAddressDrops,
                isisCorruptedLSPDetected,
                isisAttemptToExceedMaxSequence,
                isisIDLenMismatch,
                isisMaxAreaAddressesMismatch,
                isisOwnLSPPurge,
                isisSequenceNumberSkip,
                isisAuthenticationTypeFailure,

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                isisAuthenticationFailure,
                isisVersionSkew,
                isisAreaMismatch,
                isisRejectedAdjacency,
                isisLSPTooLargeToPropagate,
                isisOrigLSPBuffSizeMismatch,
                isisProtocolsSupportedMismatch,
                isisAdjacencyChange,
                isisLSPErrorDetected
            }
            STATUS current
            DESCRIPTION
                "The collections of notifications sent by an IS."
        ::= { isisGroups 5 }

        isisISPDUCounterGroup OBJECT-GROUP
            OBJECTS {
                isisPacketCountIIHello,
                isisPacketCountISHello,
                isisPacketCountESHello,
                isisPacketCountLSP,
                isisPacketCountCSNP,
                isisPacketCountPSNP,
                isisPacketCountUnknown
            }
            STATUS current
            DESCRIPTION
                "The collections of objects used to count protocol PDUs."
        ::= { isisGroups 6 }

        isisRATableGroup OBJECT-GROUP
            OBJECTS {
                isisRAExistState,
                isisRAAdminState,
                isisRAAddrPrefix,
                isisRAMapType,
                isisRAMetric,
                isisRAMetricType,
                isisRASNPAAddress,
                isisRASNPAMask,
                isisRASNPAPrefix,
                isisRAType
            }
            STATUS current
            DESCRIPTION
                "The collections of objects used to manage the

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                 reachable NSAP prefixes."
        ::= { isisGroups 7 }

        isisISIPRADestGroup OBJECT-GROUP
            OBJECTS {
                isisIPRANextHopType,
                isisIPRANextHop,
                isisIPRAType,
                isisIPRAExistState,
                isisIPRAAdminState,
                isisIPRAMetric,
                isisIPRAFullMetric,
                isisIPRAMetricType,
                isisIPRASNPAAddress,
                isisIPRASourceType
            }
            STATUS current
            DESCRIPTION
                "The collections of objects used to manage configured
                 IP addresses."
        ::= { isisGroups 8 }

        isisLSPGroup OBJECT-GROUP
            OBJECTS {
                isisLSPSeq,
                isisLSPZeroLife,
                isisLSPChecksum,
                isisLSPLifetimeRemain,
                isisLSPPDULength,
                isisLSPAttributes,
                isisLSPTLVSeq,
                isisLSPTLVChecksum,
                isisLSPTLVType,
                isisLSPTLVLen,
                isisLSPTLVValue
            }
            STATUS current
            DESCRIPTION
                "The collections of objects used to observe the LSP
                 Database."
        ::= { isisGroups 9 }

    END

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    5.  IANA Considerations

       The MIB module in this document uses the following IANA-assigned
       OBJECT IDENTIFIER values recorded in the SMI Numbers registry:

          Descriptor        OBJECT IDENTIFIER value
          ----------        -----------------------

          isisMIB           { mib-2 138 }

    6.  Acknowledgements

       This MIB is based on a March 1994 document by Chris Gunner, who
       should be held blameless for the errors introduced since then.  This
       version has been modified to include MIB-II syntax, to exclude
       portions of the protocol that are not relevant to IP, such as the
       ES-IS protocol, and to add management support for current practice.

       We would like to thank the following individuals for constructive and
       valuable comments: Mike Bartlett, Neal Castagnoli, Ken Chapman, Joan
       Cucchiara, Satish Dattatri, Nagi Jonnala, Adrian Farrel, Shamik
       Ganguly, Les Ginsberg, Don Goodspeed, Jeff Gross, Jim Halpin, Jon
       Harrison, Dimitri Haskin, C. M. Heard, Peter Higginson, Christian
       Hopps, Laura Liu, Gavin McPherson, Kay Noguchi, Serge Maskalik, Z.
       Opalka, Jeff Pickering, Sundar Ramachandran, Swaminatha Ramalingam,
       Aravind Ravikumar, Juergen Schoenwaelder, Koen Vermeulen, Hans De
       Vleeschouwer, Bert Wijnen, and Bingzhang Zhao.

    7.  Security Considerations

       Management information defined in this MIB may be considered
       sensitive in some network environments.

    7.1.  Discussion

       This MIB may be used to manage an IP router, which is used to direct
       network traffic.  The control of network traffic allows an attacker
       to deny service to a region of the network or to forward traffic to
       adversaries.  By raising or lowering metrics, traffic may be directed
       to insecure portions of the network.  By disabling the protocol on an
       interface, the network may be partitioned.  Changes to the network
       topology will force all routers to recompute their routes.  Periodic
       route changes have brought down networks in the past by subjecting
       routers to stressful recomputations.

       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

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       environments.  The support for SET operations in a non-secure
       environment without proper protection can have a negative effect on
       network operations.  Authentication of received SNMP requests and
       controlled access to management information should be employed in
       such environments.

       We identify a set of threats and then list attributes that can be
       used in each form of attack.  We discuss the effects that can be
       obtained by a single change to the variable in each class.

    7.2.  Threats

          - Drop an Adjacency
          - Drop all Peers
          - Drop Subnetwork
          - Split the Network
          - Intermittent Outages
          - Redirect Traffic
          - Delay Convergence
          - Avoid Detection
          - Prevent Updates
          - Hijack LAN
          - Create Problems for CLNS Networks

    7.2.1.  Drop an Adjacency

       By changing attributes that are used to peer, we can disrupt an
       adjacency and bring a link down.

          isisCirc3WayEnabled
          isisCircAdminState
          isisCircExistState
          isisCircLevelDRHelloTimer
          isisCircLevelHelloTimer
          isisCircLevelType
          isisCircSmallHellos

    7.2.2.  Drop All Adjacencies

       These attributes can be used to break some or all of a router's
       adjacencies.  In the case of System ID, the adjacency may be
       restored.  However, it will subject the network to additional stress.

          isisSysLevelType
          isisManAreaAddrExistState
          isisSysAdminState
          isisSysID

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    7.2.3.  Drop Subnetwork

       This attribute can be used to stop advertisement of a subnetwork
       reachable through a single interface.

          isisCircPassiveCircuit

    7.2.4.  Split the Network

       If the network design depends upon Wide Metrics or TE, we can use
       these attributes to prevent traffic from passing through a router.

          isisSysLevelMetricStyle
          isisSysLevelOrigLSPBuffSize
          isisSysLevelSPFConsiders
          isisSysLevelTEEnabled
          isisSysReceiveLSPBufferSize

    7.2.5.  Intermittent Outages

       We can use these attributes to subject the network to a series of
       topology changes, or otherwise force extensive recomputations of
       routes.

          isisSysLevelMinLSPGenInt
          isisSysLevelSetOverload
          isisSysLevelSetOverloadUntil
          isisSysMaxAge
          isisSysMaxLSPGenInt
          isisSysL2toL1Leaking
          isisSysID

    7.2.6.  Redirect Traffic

       By changing attributes such as metrics, we can push traffic to
       different parts of the network.  This may allow an intruder to
       observe data traffic from otherwise remote parts of the network.

       We may also use these attributes to deny service to parts of the
       network.

          isisSysMaxPathSplits
          isisCircLevelMetric
          isisCircLevelWideMetric
          isisIPRAAdminState
          isisIPRAExistState
          isisIPRAFullMetric
          isisIPRAMetric

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          isisIPRAMetricType
          isisIPRANextHop
          isisIPRANextHopType
          isisIPRASNPAAddress
          isisIPRAType
          isisRedistributeAddrExistState
          isisSummAddrExistState
          isisSummAddrFullMetric
          isisSummAddrMetric
          isisSysL2toL1Leaking

    7.2.7.  Delay Convergence

       These attributes can be used to slow convergence by increasing the
       minimal interval required to update a packet.

          isisCircLevelCSNPInterval
          isisCircLevelLSPThrottle
          isisCircLevelMinLSPRetransInt
          isisCircLevelPartSNPInterval
          isisSysWaitTime
          isisCircPassiveCircuit

    7.2.8.  Avoid Detection

       By turning off traps, we can prevent a Network Management station
       from observing problems in the network caused by other aspects of an
       attack.

          isisSysNotificationEnable

    7.2.9.  Prevent Updates

       Mesh Groups can be used to prevent the transmission of Link State
       PDUs on certain interfaces, delaying or preventing the propagation of
       updates.

          isisCircMeshGroup
          isisCircMeshGroupEnabled

    7.2.10. Hijack LAN

       If we have compromised a router, we can use this attribute to become
       the designated router and lie about the topology of a LAN.

          isisCircLevelISPriority

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    7.2.11.  Create Problems for CLNS Networks

       This attribute can be used to modify the handling of CLNS traffic.

          isisRAAddrPrefix
          isisRAAdminState
          isisRAExistState
          isisRAMapType
          isisRAMetric
          isisRAMetricType
          isisRASNPAAddress
          isisRASNPAMask
          isisRASNPAPrefix
          isisRAType
          isisSysPollESHelloRate

    7.2.12.  Mostly Harmless

       The following writable attributes do not pose a known security risk.

          isisCircExtDomain
          isisCircExtendedCircID
          isisCircIfIndex
          isisCircLevelHelloMultiplier
          isisCircType

    7.2.13.  Recommendations

       Much of the MIB is used to set or read attributes which are readily
       visible to any intruder who has access to traffic.  None of the
       security attributes are setable or visible through the MIB.  Read
       access to the MIB does not pose additional risks or vulnerabilities.

       If write access is to be provided, it is RECOMMENDED that
       implementers consider the security features as provided by the SNMPv3
       framework (see [RFC3410], section 8), including full support for the
       SNMPv3 cryptographic mechanisms (for authentication and privacy).

       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.

       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

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       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.

    8.  Normative References

       [ISO10589] ISO 10589, "Intermediate system to Intermediate system
                  routeing information exchange protocol for use in
                  conjunction with the Protocol for providing the
                  Connectionless-mode Network Service (ISO 8473)," ISO/IEC
                  10589:2002.

       [ISO10733] ISO 10733, "Information Processing Systems - Open Systems
                  Interconnection - Specification of the elements of
                  Management Information related to OSI Network layer
                  Standards", September 1998.

       [RFC2119]  Bradner, S., "Key words for use in RFCs to Indicate
                  Requirement Levels", BCP 14, RFC 2119, March 1997.

       [RFC1195]  Callon, R., "Use of OSI IS-IS for routing in TCP/IP and
                  dual environments", RFC 1195, December 1990.

       [RFC2863]  McCloghrie, K. and F. Kastenholz, "The Interfaces Group
                  MIB", RFC 2863, June 2000.

       [RFC3289]  Baker, F., Chan, K., and A. Smith, "Management Information
                  Base for the Differentiated Services Architecture", RFC
                  3289, May 2002.

       [RFC3411]  Harrington, D., Presuhn, R., and B. Wijnen, "An
                  Architecture for Describing Simple Network Management
                  Protocol (SNMP) Management Frameworks", STD 62, RFC 3411,
                  December 2002.

       [RFC2578]  McCloghrie, K., Perkins, D., and J. Schoenwaelder,
                  "Structure of Management Information Version 2 (SMIv2)",
                  STD 58, RFC 2578, April 1999.

       [RFC2579]  McCloghrie, K., Perkins, D., and J. Schoenwaelder,
                  "Textual Conventions for SMIv2", STD 58, RFC 2579, April
                  1999.

       [RFC2580]  McCloghrie, K., Perkins, D., and J. Schoenwaelder,
                  "Conformance Statements for SMIv2", STD 58, RFC 2580,
                  April 1999.

    Parker                      Standards Track                   [Page 101]

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       [RFC4001]  Daniele, M., Haberman, B., Routhier, S., and J.
                  Schoenwaelder, "Textual Conventions for Internet Network
                  Addresses", RFC 4001, February 2005.

    9.  Informative References

       [RFC2973]  Balay, R., Katz, D., and J. Parker, "IS-IS Mesh Groups",
                  RFC 2973, October 2000.

       [RFC3373]  Katz, D. and R. Saluja, "Three-Way Handshake for
                  Intermediate System to Intermediate System (IS-IS) Point-
                  to-Point Adjacencies", RFC 3373, September 2002.

       [RFC3410]  Case, J., Mundy, R., Partain, D., and B. Stewart,
                  "Introduction and Applicability Statements for Internet-
                  Standard Management Framework", RFC 3410, December 2002.

    Authors' Address

       Jeff Parker
       Department of Computer Science
       Middlebury College,
       Middlebury, Vermont 05753

       EMail: jeffp@middlebury.edu

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    Full Copyright Statement

       Copyright (C) The Internet Society (2006).

       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.

       This document and the information contained herein are provided on an
       "AS IS" basis and THE CONTRIBUTOR, THE ORGANIZATION HE/SHE REPRESENTS
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    Parker                      Standards Track                   [Page 103]