





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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   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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   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.









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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



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      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.




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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






































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