    Network Working Group                                 B. Stewart, Editor
    Request for Comments: 1317                                  Xyplex, Inc.
                                                                  April 1992

                      Definitions of Managed Objects for
                          RS-232-like Hardware Devices

    Status of this Memo

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

    1.  Abstract

       This memo defines a portion of the Management Information Base (MIB)
       for use with network management protocols in TCP/IP based internets.
       In particular, it defines objects for the management of RS-232-like
       devices.

    2.  The Network Management Framework

       The Internet-standard Network Management Framework consists of three
       components.  They are:

       RFC 1155 which defines the SMI, the mechanisms used for describing
       and naming objects for the purpose of management. RFC 1212 defines a
       more concise description mechanism, which is wholly consistent with
       the SMI.

       RFC 1156 which defines MIB-I, the core set of managed objects for the
       Internet suite of protocols.  RFC 1213, defines MIB-II, an evolution
       of MIB-I based on implementation experience and new operational
       requirements.

       RFC 1157 which defines the SNMP, the protocol used for network access
       to managed objects.

       The Framework permits new objects to be defined for the purpose of
       experimentation and evaluation.

    3.  Objects

       Managed objects are accessed via a virtual information store, termed
       the Management Information Base or MIB. Objects in the MIB are

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    RFC 1317                    RS-232-LIKE MIB                   April 1992

       defined using the subset of Abstract Syntax Notation One (ASN.1) [7]
       defined in the SMI.  In particular, each object has a name, a syntax,
       and an encoding.  The name is an object identifier, an
       administratively assigned name, which specifies an object type.

       The object type together with an object instance serves to uniquely
       identify a specific instantiation of the object. For human
       convenience, we often use a textual string, termed the OBJECT
       DESCRIPTOR, to also refer to the object type.

       The syntax of an object type defines the abstract data structure
       corresponding to that object type.  The ASN.1 language is used for
       this purpose.  However, the SMI [3] purposely restricts the ASN.1
       constructs which may be used. These restrictions are explicitly made
       for simplicity.

       The encoding of an object type is simply how that object type is
       represented using the object type's syntax. Implicitly tied to the
       notion of an object type's syntax and encoding is how the object type
       is represented when being transmitted on the network.

       The SMI specifies the use of the basic encoding rules of ASN.1 [8],
       subject to the additional requirements imposed by the SNMP.

    3.1.  Format of Definitions

       Section 5 contains the specification of all object types contained in
       this MIB module.  The object types are defined using the conventions
       defined in the SMI, as amended by the extensions specified in [9,10].

    4.  Overview

       The RS-232-like Hardware Device MIB applies to interface ports that
       might logically support the Interface MIB, a Transmission MIB, or the
       Character MIB.  The most common example is an RS-232 port with modem
       signals.

       The RS-232-like MIB is one of a set of MIBs designed for
       complementary use.  At this writing, the set comprises:

            Character MIB
            PPP MIB
            RS-232-like MIB
            Parallel-printer-like MIB

       The RS-232-like MIB and the Parallel-printer-like MIB represent the
       physical layer, providing service to higher layers such as the
       Character MIB or PPP MIB.  Further MIBs may appear above these.

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    RFC 1317                    RS-232-LIKE MIB                   April 1992

       The following diagram shows two possible "MIB stacks", each using the
       RS-232-like MIB.

                                       .-----------------.
            .-----------------.        |  Standard MIB   |
            |   Telnet MIB    |        | Interface Group |
            |-----------------|        |-----------------|
            |  Character MIB  |        |     PPP MIB     |
            |-----------------|        |-----------------|
            | RS-232-like MIB |        | RS-232-like MIB |
            `-----------------'        `-----------------'

       The intent of the model is for the physical-level MIBs to represent
       the lowest level, regardless of the higher level that may be using
       it.  In turn, separate higher level MIBs represent specific
       applications, such as a terminal (the Character MIB) or a network
       connection (the PPP MIB).

       The RS-232-like Hardware Device MIB is mandatory for all systems that
       have such a hardware port supporting services managed through some
       other MIB, for example, the Character MIB or PPP MIB.

       The MIB includes multiple similar types of hardware, and as a result
       contains objects not applicable to all of those types.  Such objects
       are in a separate branch of the MIB, which is required when
       applicable and otherwise absent.

       The RS-232-like Hardware Port MIB includes RS-232, RS-422, RS-423,
       V.35, and other asynchronous or synchronous, serial physical links
       with a similar set of control signals.

       The MIB contains objects that relate to physical layer connections.
       Such connections may provide interesting hardware signals (other than
       for basic data transfer), such as RNG and DCD.  Hardware ports also
       have such attributes as speed and bits per character.

       Usefulness of error counters in this MIB depends on the presence of
       non-error character counts in higher level MIBs.

       The MIB comprises one base object and four tables, detailed in the
       following sections.  The tables contain objects for all ports,
       asynchronous ports, and input and output control signals.

    Character MIB Working Group                                     [Page 3]

    RFC 1317                    RS-232-LIKE MIB                   April 1992

    5.  Definitions

                   RFC1317-MIB DEFINITIONS ::= BEGIN

                        IMPORTS
                           Counter
                                   FROM RFC1155-SMI
                           transmission
                                   FROM RFC1213-MIB
                           OBJECT-TYPE
                                   FROM RFC-1212;

           -- this is the MIB module for RS-232-like hardware devices

           rs232    OBJECT IDENTIFIER ::= { transmission 33 }

           -- the generic RS-232-like group

           -- Implementation of this group is mandatory for all
           -- systems that have RS-232-like hardware ports
           -- supporting higher level services such as character
           -- streams or network interfaces

           rs232Number OBJECT-TYPE
               SYNTAX INTEGER
               ACCESS read-only
               STATUS mandatory
               DESCRIPTION
                   "The number of ports (regardless of their current
                   state) in the RS-232-like general port table."
               ::= { rs232 1 }

           -- the RS-232-like general Port table

           rs232PortTable OBJECT-TYPE
               SYNTAX SEQUENCE OF Rs232PortEntry
               ACCESS not-accessible
               STATUS mandatory
               DESCRIPTION
                   "A list of port entries.  The number of entries is
                   given by the value of rs232Number."
               ::= { rs232 2 }

           rs232PortEntry OBJECT-TYPE
               SYNTAX Rs232PortEntry
               ACCESS not-accessible

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               STATUS mandatory
               DESCRIPTION
                   "Status and parameter values for a port."
               INDEX { rs232PortIndex }
               ::= { rs232PortTable 1 }

           Rs232PortEntry ::=
               SEQUENCE {
                   rs232PortIndex
                       INTEGER,
                   rs232PortType
                       INTEGER,
                   rs232PortInSigNumber
                       INTEGER,
                   rs232PortOutSigNumber
                       INTEGER,
                   rs232PortInSpeed
                       INTEGER,
                   rs232PortOutSpeed
                       INTEGER    }

           rs232PortIndex OBJECT-TYPE
               SYNTAX INTEGER
               ACCESS read-only
               STATUS mandatory
               DESCRIPTION
                   "A unique value for each port.  Its value ranges
                   between 1 and the value of rs232Number.  By
                   convention and if possible, hardware port numbers
                   map directly to external connectors.  The value for
                   each port must remain constant at least from one
                   re-initialization of the network management agent to
                   the next."
               ::= { rs232PortEntry 1 }

           rs232PortType OBJECT-TYPE
               SYNTAX INTEGER { other(1), rs232(2), rs422(3),
                                rs423(4), v35(5) }
               ACCESS read-only
               STATUS mandatory
               DESCRIPTION
                   "The port's hardware type."
               ::= { rs232PortEntry 2 }

           rs232PortInSigNumber OBJECT-TYPE
               SYNTAX INTEGER
               ACCESS read-only
               STATUS mandatory

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               DESCRIPTION
                   "The number of input signals for the port in the
                   input signal table (rs232PortInSigTable).  The table
                   contains entries only for those signals the software
                   can detect."
               ::= { rs232PortEntry 3 }

           rs232PortOutSigNumber OBJECT-TYPE
               SYNTAX INTEGER
               ACCESS read-only
               STATUS mandatory
               DESCRIPTION
                   "The number of output signals for the port in the
                   output signal table (rs232PortOutSigTable).  The
                   table contains entries only for those signals the
                   software can assert."
               ::= { rs232PortEntry 4 }

           rs232PortInSpeed OBJECT-TYPE
               SYNTAX INTEGER
               ACCESS read-write
               STATUS mandatory
               DESCRIPTION
                   "The port's input speed in bits per second."
               ::= { rs232PortEntry 5 }

           rs232PortOutSpeed OBJECT-TYPE
               SYNTAX INTEGER
               ACCESS read-write
               STATUS mandatory
               DESCRIPTION
                   "The port's output speed in bits per second."
               ::= { rs232PortEntry 6 }

           -- the RS-232-like Asynchronous Port group

           -- Implementation of this group is mandatory if the system
           -- has any asynchronous ports.  Otherwise it is not
           -- present.

           rs232AsyncPortTable OBJECT-TYPE
               SYNTAX SEQUENCE OF Rs232AsyncPortEntry
               ACCESS not-accessible
               STATUS mandatory
               DESCRIPTION
                   "A list of asynchronous port entries.  The maximum
                   entry number is given by the value of rs232Number.

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                   Entries need not exist for synchronous ports."
               ::= { rs232 3 }

           rs232AsyncPortEntry OBJECT-TYPE
               SYNTAX Rs232AsyncPortEntry
               ACCESS not-accessible
               STATUS mandatory
               DESCRIPTION
                   "Status and parameter values for an asynchronous
                   port."
               INDEX { rs232AsyncPortIndex }
               ::= { rs232AsyncPortTable 1 }

           Rs232AsyncPortEntry ::=
               SEQUENCE {
                   rs232AsyncPortIndex
                       INTEGER,
                   rs232AsyncPortBits
                       INTEGER,
                   rs232AsyncPortStopBits
                       INTEGER,
                   rs232AsyncPortParity
                       INTEGER,
                   rs232AsyncPortAutobaud
                       INTEGER,
                   rs232AsyncPortParityErrs
                       Counter,
                   rs232AsyncPortFramingErrs
                       Counter,
                   rs232AsyncPortOverrunErrs
                       Counter

               }

           rs232AsyncPortIndex OBJECT-TYPE
               SYNTAX INTEGER
               ACCESS read-only
               STATUS mandatory
               DESCRIPTION
                   "A unique value for each port.  Its value is the
                   same as rs232PortIndex for the port."
               ::= { rs232AsyncPortEntry 1 }

           rs232AsyncPortBits OBJECT-TYPE
               SYNTAX INTEGER (5..8)
               ACCESS read-write
               STATUS mandatory
               DESCRIPTION

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                   "The port's number of bits in a character."
               ::= { rs232AsyncPortEntry 2 }

           rs232AsyncPortStopBits OBJECT-TYPE
               SYNTAX INTEGER { one(1), two(2),
                                one-and-half(3), dynamic(4) }
               ACCESS read-write
               STATUS mandatory
               DESCRIPTION
                   "The port's number of stop bits."
               ::= { rs232AsyncPortEntry 3 }

           rs232AsyncPortParity OBJECT-TYPE
               SYNTAX INTEGER { none(1), odd(2), even(3),
                                mark(4), space(5) }
               ACCESS read-write
               STATUS mandatory
               DESCRIPTION
                   "The port's sense of a character parity bit."
               ::= { rs232AsyncPortEntry 4 }

           rs232AsyncPortAutobaud OBJECT-TYPE
               SYNTAX INTEGER { enabled(1), disabled(2) }
               ACCESS read-write
               STATUS mandatory
               DESCRIPTION
                   "A control for the port's ability to automatically
                   sense input speed.

                   When rs232PortAutoBaud is 'enabled', a port may
                   autobaud to values different from the set values for
                   speed, parity, and character size.  As a result a
                   network management system may temporarily observe
                   values different from what was previously set."
               ::= { rs232AsyncPortEntry 5 }

           rs232AsyncPortParityErrs OBJECT-TYPE
               SYNTAX Counter
               ACCESS read-only
               STATUS mandatory
               DESCRIPTION
                   "Total number of characters with a parity error,
                   input from the port since system re-initialization
                   and while the port state was 'up' or 'test'."
               ::= { rs232AsyncPortEntry 6 }

           rs232AsyncPortFramingErrs OBJECT-TYPE
               SYNTAX Counter

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               ACCESS read-only
               STATUS mandatory
               DESCRIPTION
                   "Total number of characters with a framing error,
                   input from the port since system re-initialization
                   and while the port state was 'up' or 'test'."
               ::= { rs232AsyncPortEntry 7 }

           rs232AsyncPortOverrunErrs OBJECT-TYPE
               SYNTAX Counter
               ACCESS read-only
               STATUS mandatory
               DESCRIPTION
                   "Total number of characters with an overrun error,
                   input from the port since system re-initialization
                   and while the port state was 'up' or 'test'."
               ::= { rs232AsyncPortEntry 8 }

           -- the RS-232-like Synchronous Port group

           -- Implementation of this group is mandatory if the system
           -- has any synchronous ports.  Otherwise it is not
           -- present.

           rs232SyncPortTable OBJECT-TYPE
               SYNTAX SEQUENCE OF Rs232SyncPortEntry
               ACCESS not-accessible
               STATUS mandatory
               DESCRIPTION
                   "A list of synchronous port entries.  The maximum
                   entry number is given by the value of rs232Number.
                   Entries need not exist for asynchronous ports."
               ::= { rs232 4 }

           rs232SyncPortEntry OBJECT-TYPE
               SYNTAX Rs232SyncPortEntry
               ACCESS not-accessible
               STATUS mandatory
               DESCRIPTION
                   "Status and parameter values for a synchronous
                   port."
               INDEX { rs232SyncPortIndex }
               ::= { rs232SyncPortTable 1 }

           Rs232SyncPortEntry ::=
               SEQUENCE {
                   rs232SyncPortIndex

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                       INTEGER,
                   rs232SyncPortClockSource
                       INTEGER,
                   rs232SyncPortFrameCheckErrs
                       Counter,
                   rs232SyncPortTransmitUnderrunErrs
                       Counter,
                   rs232SyncPortReceiveOverrunErrs
                       Counter,
                   rs232SyncPortInterruptedFrames
                       Counter,
                   rs232SyncPortAbortedFrames
                       Counter
               }

           rs232SyncPortIndex OBJECT-TYPE
               SYNTAX INTEGER
               ACCESS read-only
               STATUS mandatory
               DESCRIPTION
                   "A unique value for each port.  Its value is the
                   same as rs232PortIndex for the port."
               ::= { rs232SyncPortEntry 1 }

           rs232SyncPortClockSource OBJECT-TYPE
               SYNTAX INTEGER  { internal(1), external(2), split(3) }
               ACCESS read-write
               STATUS mandatory
               DESCRIPTION
                   "Source of the port's bit rate clock. 'split' means
                   the tranmit clock is internal and the receive clock
                   is external."
               ::= { rs232SyncPortEntry 2 }

           rs232SyncPortFrameCheckErrs OBJECT-TYPE
               SYNTAX Counter
               ACCESS read-only
               STATUS mandatory
               DESCRIPTION
                   "Total number of frames with an invalid frame check
                   sequence, input from the port since system
                   re-initialization and while the port state was 'up'
                   or 'test'."
               ::= { rs232SyncPortEntry 3 }

           rs232SyncPortTransmitUnderrunErrs OBJECT-TYPE
               SYNTAX Counter
               ACCESS read-only

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               STATUS mandatory
               DESCRIPTION
                   "Total number of frames that failed to be
                   transmitted on the port since system
                   re-initialization and while the port state was 'up'
                   or 'test' because data was not available to the
                   transmitter in time."
               ::= { rs232SyncPortEntry 4 }

           rs232SyncPortReceiveOverrunErrs OBJECT-TYPE
               SYNTAX Counter
               ACCESS read-only
               STATUS mandatory
               DESCRIPTION
                   "Total number of frames that failed to be received
                   on the port since system re-initialization and while
                   the port state was 'up' or 'test' because the
                   receiver did not accept the data in time."
               ::= { rs232SyncPortEntry 5 }

           rs232SyncPortInterruptedFrames OBJECT-TYPE
               SYNTAX Counter
               ACCESS read-only
               STATUS mandatory
               DESCRIPTION
                   "Total number of frames that failed to be received
                   or transmitted on the port due to loss of modem
                   signals since system re-initialization and while the
                   port state was 'up' or 'test'."
               ::= { rs232SyncPortEntry 6 }

           rs232SyncPortAbortedFrames OBJECT-TYPE
               SYNTAX Counter
               ACCESS read-only
               STATUS mandatory
               DESCRIPTION
                   "Number of frames aborted on the port due to
                   receiving an abort sequence since system
                   re-initialization and while the port state was 'up'
                   or 'test'."
               ::= { rs232SyncPortEntry 7 }

           -- the Input Signal table

           rs232InSigTable OBJECT-TYPE
               SYNTAX SEQUENCE OF Rs232InSigEntry
               ACCESS not-accessible

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               STATUS mandatory
               DESCRIPTION
                   "A list of port input control signal entries."
               ::= { rs232 5 }

           rs232InSigEntry OBJECT-TYPE
               SYNTAX Rs232InSigEntry
               ACCESS not-accessible
               STATUS mandatory
               DESCRIPTION
                   "Input control signal status for a hardware port."
               INDEX { rs232InSigPortIndex, rs232InSigName }
               ::= { rs232InSigTable 1 }

           Rs232InSigEntry ::=
               SEQUENCE {
                   rs232InSigPortIndex
                       INTEGER,
                   rs232InSigName
                       INTEGER,
                   rs232InSigState
                       INTEGER,
                   rs232InSigChanges
                       Counter
               }

           rs232InSigPortIndex OBJECT-TYPE
               SYNTAX INTEGER
               ACCESS read-only
               STATUS mandatory
               DESCRIPTION
                   "The value of rs232PortIndex for the port to which
                   this entry belongs."
               ::= { rs232InSigEntry 1 }

           rs232InSigName OBJECT-TYPE
               SYNTAX INTEGER { rts(1), cts(2), dsr(3), dtr(4), ri(5),
                                dcd(6), sq(7), srs(8), srts(9),
                                scts(10), sdcd(11) }
               ACCESS read-only
               STATUS mandatory
               DESCRIPTION
                   "Identification of a hardware signal, as follows:

                       rts    Request to Send
                       cts    Clear to Send
                       dsr    Data Set Ready
                       dtr    Data Terminal Ready

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                       ri     Ring Indicator
                       dcd    Received Line Signal Detector
                       sq     Signal Quality Detector
                       srs    Data Signaling Rate Selector
                       srts   Secondary Request to Send
                       scts   Secondary Clear to Send
                       sdcd   Secondary Received Line Signal Detector
                   "
               REFERENCE
                   "EIA Standard RS-232-C, August 1969."
               ::= { rs232InSigEntry 2 }

           rs232InSigState OBJECT-TYPE
               SYNTAX INTEGER { none(1), on(2), off(3) }
               ACCESS read-only
               STATUS mandatory
               DESCRIPTION
                   "The current signal state."
               ::= { rs232InSigEntry 3 }

           rs232InSigChanges OBJECT-TYPE
               SYNTAX Counter
               ACCESS read-only
               STATUS mandatory
               DESCRIPTION
                   "The number of times the signal has changed from
                   'on' to 'off' or from 'off' to 'on'."
               ::= { rs232InSigEntry 4 }

           -- the Output Signal table

           rs232OutSigTable OBJECT-TYPE
               SYNTAX SEQUENCE OF Rs232OutSigEntry
               ACCESS not-accessible
               STATUS mandatory
               DESCRIPTION
                   "A list of port output control signal entries."
               ::= { rs232 6 }

           rs232OutSigEntry OBJECT-TYPE
               SYNTAX Rs232OutSigEntry
               ACCESS not-accessible
               STATUS mandatory
               DESCRIPTION
                   "Output control signal status for a hardware port."
               INDEX { rs232OutSigPortIndex, rs232OutSigName }
               ::= { rs232OutSigTable 1 }

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           Rs232OutSigEntry ::=
               SEQUENCE {
                   rs232OutSigPortIndex
                       INTEGER,
                   rs232OutSigName
                       INTEGER,
                   rs232OutSigState
                       INTEGER,
                   rs232OutSigChanges
                       Counter
               }

           rs232OutSigPortIndex OBJECT-TYPE
               SYNTAX INTEGER
               ACCESS read-only
               STATUS mandatory
               DESCRIPTION
                   "The value of rs232PortIndex for the port to which
                   this entry belongs."
               ::= { rs232OutSigEntry 1 }

           rs232OutSigName OBJECT-TYPE
               SYNTAX INTEGER { rts(1), cts(2), dsr(3), dtr(4), ri(5),
                                dcd(6), sq(7), srs(8), srts(9),
                                scts(10), sdcd(11) }
               ACCESS read-only
               STATUS mandatory
               DESCRIPTION
                   "Identification of a hardware signal, as follows:

                       rts    Request to Send
                       cts    Clear to Send
                       dsr    Data Set Ready
                       dtr    Data Terminal Ready
                       ri     Ring Indicator
                       dcd    Received Line Signal Detector
                       sq     Signal Quality Detector
                       srs    Data Signaling Rate Selector
                       srts   Secondary Request to Send
                       scts   Secondary Clear to Send
                       sdcd   Secondary Received Line Signal Detector
                   "
               REFERENCE
                   "EIA Standard RS-232-C, August 1969."
               ::= { rs232OutSigEntry 2 }

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           rs232OutSigState OBJECT-TYPE
               SYNTAX INTEGER { none(1), on(2), off(3) }
               ACCESS read-only
               STATUS mandatory
               DESCRIPTION
                   "The current signal state."
               ::= { rs232OutSigEntry 3 }

           rs232OutSigChanges OBJECT-TYPE
               SYNTAX Counter
               ACCESS read-only
               STATUS mandatory
               DESCRIPTION
                   "The number of times the signal has changed from
                   'on' to 'off' or from 'off' to 'on'."
               ::= { rs232OutSigEntry 4 }

           END

    6.  Acknowledgements

       Based on several private MIBs, this document was produced by the
       Character MIB Working Group:

          Anne Ambler, Spider
          Charles Bazaar, Emulex
          Christopher Bucci, Datability
          Anthony Chung, Hughes LAN Systems
          George Conant, Xyplex
          John Cook, Chipcom
          James Davin, MIT-LCS
          Shawn Gallagher, DEC
          Tom Grant, Xylogics
          Frank Huang, Emulex
          David Jordan, Emulex
          Satish Joshi, SynOptics
          Frank Kastenholz, Clearpoint
          Ken Key, University of Tennessee
          Jim Kinder, Fibercom
          Rajeev Kochhar, 3Com
          John LoVerso, Xylogics
          Keith McCloghrie, Hughes LAN Systems
          Donalpd Merritt, BRL
          David Perkins, 3Com
          Jim Reinstedler, Ungerman-Bass
          Marshall Rose, PSI
          Ron Strich, SSDS
          Dean Throop, DG

    Character MIB Working Group                                    [Page 15]

    RFC 1317                    RS-232-LIKE MIB                   April 1992

          Bill Townsend, Xylogics
          Jesse Walker, DEC
          David Waitzman, BBN
          Bill Westfield, cisco

    7.  References

       [1] Cerf, V., "IAB Recommendations for the Development of Internet
           Network Management Standards", RFC 1052, NRI, April 1988.

       [2] Cerf, V., "Report of the Second Ad Hoc Network Management Review
           Group", RFC 1109, NRI, August 1989.

       [3] Rose M., and K. McCloghrie, "Structure and Identification of
           Management Information for TCP/IP-based internets", RFC 1155,
           Performance Systems International, Hughes LAN Systems, May 1990.

       [4] McCloghrie K., and M. Rose, "Management Information Base for
           Network Management of TCP/IP-based internets", RFC 1156, Hughes
           LAN Systems, Performance Systems International, May 1990.

       [5] Case, J., Fedor, M., Schoffstall, M., and J. Davin, Simple
           Network Management Protocol", RFC 1157, SNMP Research,
           Performance Systems International, Performance Systems
           International, MIT Laboratory for Computer Science, May 1990.

       [6] McCloghrie K., and M. Rose, Editors, "Management Information Base
           for Network Management of TCP/IP-based internets", RFC 1213,
           Performance Systems International, March 1991.

       [7] Information processing systems - Open Systems Interconnection -
           Specification of Abstract Syntax Notation One (ASN.1),
           International Organization for Standardization, International
           Standard 8824, December 1987.

       [8] Information processing systems - Open Systems Interconnection -
           Specification of Basic Encoding Rules for Abstract Notation One
           (ASN.1), International Organization for Standardization,
           International Standard 8825, December 1987.

       [9] Rose, M., and K. McCloghrie, Editors, "Concise MIB Definitions",
           RFC 1212, Performance Systems International, Hughes LAN Systems,
           March 1991.

      [10] Rose, M., Editor, "A Convention for Defining Traps for use with
           the SNMP", RFC 1215, Performance Systems International, March
           1991.

    Character MIB Working Group                                    [Page 16]

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    8.  Security Considerations

       Security issues are not discussed in this memo.

    9.  Author's Address

       Bob Stewart
       Xyplex, Inc.
       330 Codman Hill Road
       Boxborough, MA 01719

       Phone: (508) 264-9900
       EMail: rlstewart@eng.xyplex.com

    Character MIB Working Group                                    [Page 17]