Network Working Group                                        S. Willis
INTERNET DRAFT                                              J. Burruss
                                         Wellfleet Communications Inc.
                                                                J. Chu
                                                              IBM Corp
                                                         December 1992


                     Definitions of Managed Objects
              for the Border Gateway Protocol (Version 4)


Status of this Memo

   This memo is an extension to the SNMP MIB.  It specifies an IAB
   standards track protocol for the Internet community, and requests
   discussion and suggestions for improvements.  The origin of this memo
   is from RFC 1269 "Definitions of Managed Objects for the Board
   Gateway Protocol (Version 3)" written by the first two authors of
   this memo.  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 managing the Border Gateway
   Protocol [11,12].


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.






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      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
   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 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].









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4.  Overview

   These objects are used to control and manage a BGP [11,12]
   implementation.

   The Border Gateway Protocol (BGP) is an inter-Autonomous System
   routing protocol.  The primary function of a BGP speaking system is
   to exchange network reachability information with other BGP systems.
   This network reachability information includes information on the
   full path of Autonomous Systems that traffic must transit to reach
   these networks.

   BGP runs over a reliable transport protocol.  This eliminates the
   need to implement explicit update fragmentation, retransmission,
   acknowledgement, and sequencing.  Any authentication scheme used by
   the transport protocol may be used in addition to BGP's own
   authentication mechanisms.

   The planned use of BGP in the Internet environment, including such
   issues as topology, the interaction between BGP and IGPs, and the
   enforcement of routing policy rules is presented in a companion
   document [12].

   Apart from a few system variables, this MIB is broken into two
   tables: the BGP Peer Table and the BGP Received Path Attribute Table.
   The Peer Table reflects information about BGP peer connections, such
   as their state and current activity.  The Received Path Attribute
   Table contains all attributes received from all peers before local
   routing policy has been applied.  The actual attributes used in
   determining a route are a subset of the received attribute table.


5.  Definitions

               RFCxxxx-MIB DEFINITIONS ::= BEGIN

               IMPORTS
                    NetworkAddress, IpAddress, Counter
                         FROM RFC1155-SMI
                    mib-2
                         FROM RFC1213-MIB
                  OBJECT-TYPE
                         FROM RFC-1212
                    TRAP-TYPE
                         FROM RFC-1215;





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               -- This MIB module uses the extended OBJECT-TYPE macro as
               -- defined in [9], and the TRAP-TYPE macro as defined
               -- in [10].

               bgp     OBJECT IDENTIFIER ::= { mib-2 15 }


               bgpVersion OBJECT-TYPE
                    SYNTAX OCTET STRING
                    ACCESS read-only
                    STATUS mandatory
                    DESCRIPTION
                         "Vector of supported BGP protocol version
                         numbers. Each peer negotiates the version from
                         this vector.  Versions are identified via the
                         string of bits contained within this object.
                         The first octet contains bits 0 to 7, the
                         second octet contains bits 8 to 15, and so on,
                         with the most significant bit referring to the
                         lowest bit number in the octet (e.g., the MSB
                         of the first octet refers to bit 0).  If a bit,
                         i, is present and set, then the version (i+1)
                         of the BGP is supported."
                    ::= { bgp 1 }

               bgpLocalAs OBJECT-TYPE
                    SYNTAX INTEGER (0..65535)
                    ACCESS read-only
                    STATUS mandatory
                    DESCRIPTION
                         "The local autonomous system number."
                    ::= { bgp 2 }

               bgpPeerTable OBJECT-TYPE
                    SYNTAX SEQUENCE OF BgpPeerEntry
                    ACCESS not-accessible
                    STATUS mandatory
                    DESCRIPTION
                         "The bgp peer table."
                    ::= { bgp 3 }

               bgpIdentifier OBJECT-TYPE
                    SYNTAX IpAddress
                    ACCESS read-only





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                    STATUS mandatory
                    DESCRIPTION
                         "The BGP Identifier of local system."
                    ::= { bgp 4 }

               bgpPeerEntry OBJECT-TYPE
                    SYNTAX BgpPeerEntry
                    ACCESS not-accessible
                    STATUS mandatory
                    DESCRIPTION
                         "Information about a BGP peer connection."
                    INDEX
                         { bgpPeerRemoteAddr }
                        ::= { bgpPeerTable 1 }

               BgpPeerEntry ::= SEQUENCE {
                    bgpPeerIdentifier
                         IpAddress,
                    bgpPeerState
                         INTEGER,
                    bgpPeerAdminStatus
                         INTEGER,
                    bgpPeerNegotiatedVersion
                         INTEGER,
                    bgpPeerLocalAddr
                         IpAddress,
                    bgpPeerLocalPort
                         INTEGER,
                    bgpPeerRemoteAddr
                         IpAddress,
                    bgpPeerRemotePort
                         INTEGER,
                    bgpPeerRemoteAs
                         INTEGER,
                    bgpPeerInUpdates
                         Counter,
                    bgpPeerOutUpdates
                         Counter,
                    bgpPeerInTotalMessages
                         Counter,
                    bgpPeerOutTotalMessages
                         Counter,
                    bgpPeerLastError
                         OCTET STRING,
                    bgpPeerFsmEstablishedTransitions





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                         Counter
                    }

               bgpPeerIdentifier OBJECT-TYPE
                    SYNTAX IpAddress
                    ACCESS read-only
                    STATUS mandatory
                    DESCRIPTION
                         "The BGP Identifier of this entry's BGP peer."
                    ::= { bgpPeerEntry 1 }

               bgpPeerState OBJECT-TYPE
                    SYNTAX INTEGER {
                         idle(1),
                         connect(2),
                         active(3),
                         opensent(4),
                         openconfirm(5),
                         established(6)
                    }
                    ACCESS read-only
                    STATUS mandatory
                    DESCRIPTION
                         "The bgp peer connection state. "
                    ::= { bgpPeerEntry 2 }

               bgpPeerAdminStatus OBJECT-TYPE
                    SYNTAX INTEGER {
                         stop(1),
                         start(2)
                    }
                    ACCESS read-write
                    STATUS mandatory
                    DESCRIPTION
                         "The desired state of the BGP connection. A
                         transition from 'stop' to 'start' will cause
                         the BGP Start Event to be generated. A
                         transition from 'start' to 'stop' will cause
                         the BGP Stop Event to be generated. This
                         parameter can be used to restart BGP peer
                         connections.  Care should be used in providing
                         write access to this object without adequate
                         authentication."
                    ::= { bgpPeerEntry 3 }






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               bgpPeerNegotiatedVersion OBJECT-TYPE
                    SYNTAX INTEGER
                    ACCESS read-only
                    STATUS mandatory
                    DESCRIPTION
                         "The negotiated version of BGP running between
                         the two peers. "
                    ::= { bgpPeerEntry 4 }

               bgpPeerLocalAddr OBJECT-TYPE
                    SYNTAX IpAddress
                    ACCESS read-only
                    STATUS mandatory
                    DESCRIPTION
                         "The local IP address of this entry's BGP
                         connection."
                    ::= { bgpPeerEntry 5 }

               bgpPeerLocalPort OBJECT-TYPE
                    SYNTAX INTEGER (0..65535)
                    ACCESS read-only
                    STATUS mandatory
                    DESCRIPTION
                         "The local port for the TCP connection between
                         the BGP peers."
                    ::= { bgpPeerEntry 6 }

               bgpPeerRemoteAddr OBJECT-TYPE
                    SYNTAX IpAddress
                    ACCESS read-only
                    STATUS mandatory
                    DESCRIPTION
                         "The remote IP address of this entry's BGP
                         peer."
                    ::= { bgpPeerEntry 7 }

               bgpPeerRemotePort OBJECT-TYPE
                    SYNTAX INTEGER (0..65535)
                    ACCESS read-only
                    STATUS mandatory
                    DESCRIPTION
                         "The remote port for the TCP connection between
                         the BGP peers.  Note that the objects
                         bgpLocalAddr, bgpLocalPort, bgpRemoteAddr and
                         bgpRemotePort provide the appropriate reference





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                         to the standard MIB TCP connection table."
                    ::= { bgpPeerEntry 8 }

               bgpPeerRemoteAs OBJECT-TYPE
                    SYNTAX INTEGER (0..65535)
                    ACCESS read-only
                    STATUS mandatory
                    DESCRIPTION
                         "The remote autonomous system number."
                    ::= { bgpPeerEntry 9 }

               bgpPeerInUpdates OBJECT-TYPE
                    SYNTAX Counter
                    ACCESS read-only
                    STATUS mandatory
                    DESCRIPTION
                         "The number of BGP UPDATE messages received on
                         this connection. This object should be
                         initialized to zero when the connection is
                         established."
                    ::= { bgpPeerEntry 10 }

               bgpPeerOutUpdates OBJECT-TYPE
                    SYNTAX Counter
                    ACCESS read-only
                    STATUS mandatory
                    DESCRIPTION
                         "The number of BGP UPDATE messages received on
                         this connection. This object should be
                         initialized to zero when the connection is
                         established."
                    ::= { bgpPeerEntry 11}

               bgpPeerInTotalMessages OBJECT-TYPE
                    SYNTAX Counter
                    ACCESS read-only
                    STATUS mandatory
                    DESCRIPTION
                         "The total number of messages received from the
                         remote peer on this connection. This object
                         should be initialized to zero when the
                         connection is established."
                    ::= { bgpPeerEntry 12 }

               bgpPeerOutTotalMessages OBJECT-TYPE





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                    SYNTAX Counter
                    ACCESS read-only
                    STATUS mandatory
                    DESCRIPTION
                         "The total number of messages transmitted to
                         the remote peer on this connection. This object
                         should be initialized to zero when the
                         connection is established."
                    ::= { bgpPeerEntry 13 }

               bgpPeerLastError OBJECT-TYPE
                    SYNTAX OCTET STRING (SIZE (2))
                    ACCESS read-only
                    STATUS mandatory
                    DESCRIPTION
                         "The last error code and subcode seen by this
                         peer on this connection. If no error has
                         occurred, this field is zero. Otherwise, the
                         first byte of this two byte OCTET STRING
                         contains the error code; the second contains
                         the subcode."
                    ::= { bgpPeerEntry 14 }

               bgpPeerFsmEstablishedTransitions OBJECT-TYPE
                    SYNTAX Counter
                    ACCESS read-only
                    STATUS mandatory
                    DESCRIPTION
                         "The total number of times the BGP FSM
                          transitioned intto the established state."
                    ::= { bgpPeerEntry 15 }



               bgpRcvdPathAttrTable OBJECT-TYPE
                    SYNTAX SEQUENCE OF BgpPathAttrEntry
                    ACCESS not-accessible
                    STATUS mandatory
                    DESCRIPTION
                         "The BGP Received Path Attribute Table contains
                         information about paths to destination networks
                         received by all peers running BGP version 3 or
                         less."
                    ::= { bgp 5 }






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               bgpPathAttrEntry OBJECT-TYPE
                    SYNTAX BgpPathAttrEntry
                    ACCESS not-accessible
                    STATUS mandatory
                    DESCRIPTION
                         "Information about a path to a network."
                    INDEX
                         { bgpPathAttrDestNetwork,
                           bgpPathAttrPeer }
                    ::= { bgpRcvdPathAttrTable 1 }

               BgpPathAttrEntry ::= SEQUENCE {
                    bgpPathAttrPeer
                         IpAddress,
                    bgpPathAttrDestNetwork
                         IpAddress,
                    bgpPathAttrOrigin
                         INTEGER,
                    bgpPathAttrASPath
                         OCTET STRING,
                    bgpPathAttrNextHop
                         IpAddress,
                    bgpPathAttrInterASMetric
                         INTEGER
                    }

               bgpPathAttrPeer OBJECT-TYPE
                    SYNTAX IpAddress
                    ACCESS read-only
                    STATUS mandatory
                    DESCRIPTION
                         "The IP address of the peer where the path
                         information
                          was learned."
                    ::= { bgpPathAttrEntry 1 }

               bgpPathAttrDestNetwork OBJECT-TYPE
                    SYNTAX IpAddress
                    ACCESS read-only
                    STATUS mandatory
                    DESCRIPTION
                         "The address of the destination network."
                    ::= { bgpPathAttrEntry 2 }

               bgpPathAttrOrigin OBJECT-TYPE





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                    SYNTAX INTEGER {
                         igp(1),-- networks are interior
                         egp(2),-- networks learned via EGP
                         incomplete(3) -- undetermined
                    }
                    ACCESS read-only
                    STATUS mandatory
                    DESCRIPTION
                         "The ultimate origin of the path information."
                    ::= { bgpPathAttrEntry 3 }

               bgpPathAttrASPath OBJECT-TYPE
                    SYNTAX OCTET STRING
                    ACCESS read-only
                    STATUS mandatory
                    DESCRIPTION
                         "The set of ASs that must be traversed to reach
                         the network. ( This object is probably best
                         represented as SEQUENCE OF INTEGER. For SMI
                         compatibility, though, it is represented as
                         OCTET STRING. Each AS is represented as a pair
                         of octets according to the following algorithm:

                              first-byte-of-pair = ASNumber / 256;
                              second-byte-of-pair = ASNumber & 255;"
                    ::= { bgpPathAttrEntry 4 }

               bgpPathAttrNextHop OBJECT-TYPE
                    SYNTAX IpAddress
                    ACCESS read-only
                    STATUS mandatory
                    DESCRIPTION
                         "The address of the border router that should
                         be used for the destination network."
                    ::= { bgpPathAttrEntry 5 }

               bgpPathAttrInterASMetric OBJECT-TYPE
                    SYNTAX IpAddress
                    ACCESS read-only
                    STATUS mandatory
                    DESCRIPTION
                         "The optional inter-AS metric. If this
                         attribute has not been provided for this route,
                         the value for this object is 0."
                    ::= { bgpPathAttrEntry 6 }





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               bgp4RcvdPathAttrTable OBJECT-TYPE
                    SYNTAX SEQUENCE OF Bgp4PathAttrEntry
                    ACCESS not-accessible
                    STATUS mandatory
                    DESCRIPTION
                         "The BGP-4 Received Path Attribute Table contains
                         information about paths to destination networks
                         received by all BGP4 peers."
                    ::= { bgp 6 }

               bgp4PathAttrEntry OBJECT-TYPE
                    SYNTAX Bgp4PathAttrEntry
                    ACCESS not-accessible
                    STATUS mandatory
                    DESCRIPTION
                         "Information about a path to a network."
                    INDEX
                         { bgp4PathAttrPeer,
                           bgp4PathAttrIpAddrPrefixLen,
                           bgp4PathAttrIpAddrPrefix }
                    ::= { bgp4RcvdPathAttrTable 1 }

               Bgp4PathAttrEntry ::= SEQUENCE {
                    bgp4PathAttrPeer
                         IpAddress,
                    bgp4PathAttrIpAddrPrefixLen
                         INTEGER,
                    bgp4PathAttrIpAddrPrefix
                         OCTET STRING,
                    bgp4PathAttrOrigin
                         INTEGER,
                    bgp4PathAttrASPathSegment
                         OCTET STRING,
                    bgp4PathAttrNextHop
                         IpAddress,
                    bgp4PathAttrMultiExitDisc
                         INTEGER,
                    bgp4PathAttrLocalPref
                         INTEGER,
                    bgp4PathAttrAtomicAggregate
                         INTEGER,
                    bgp4PathAttrAggregator





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                         INTEGER
                    }

               bgp4PathAttrPeer OBJECT-TYPE
                    SYNTAX IpAddress
                    ACCESS read-only
                    STATUS mandatory
                    DESCRIPTION
                         "The IP address of the peer where the path
                         information was learned."
                    ::= { bgp4PathAttrEntry 1 }

               bgp4PathAttrIpAddrPrefixLen OBJECT-TYPE
                    SYNTAX INTEGER (0..255)
                    ACCESS read-only
                    STATUS mandatory
                    DESCRIPTION
                         "Length in bits of the IP address prefix in the
                          Network Layer Reachability Information field."
                    ::= { bgp4PathAttrEntry 2 }

               bgp4PathAttrIpAddrPrefix OBJECT-TYPE
                    SYNTAX OCTET STRING
                    ACCESS read-only
                    STATUS mandatory
                    DESCRIPTION
                         "An IP address prefix in the Network Layer
                          Reachability Information field.  This string
                          contains as many octets as necessary to hold
                          a prefix of the length specified by
                          bgp4PathAttrIpAddrPrefixLen.  Any bits
                          beyond the length specified by
                          bgp4PathAttrIpAddrPrefixLen are zeroed."
                    ::= { bgp4PathAttrEntry 3 }

               bgp4PathAttrOrigin OBJECT-TYPE
                    SYNTAX INTEGER {
                         igp(1),-- networks are interior
                         egp(2),-- networks learned via EGP
                         incomplete(3) -- undetermined
                    }
                    ACCESS read-only
                    STATUS mandatory
                    DESCRIPTION
                         "The ultimate origin of the path





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                          information."
                    ::= { bgp4PathAttrEntry 4 }

               bgp4PathAttrASPathSegment OBJECT-TYPE
                    SYNTAX OCTET STRING
                    ACCESS read-only
                    STATUS mandatory
                    DESCRIPTION
                         "The sequence of AS path segments. Each AS
                          path segment is represented by a triple
                         <type, length, value>.

                         The type is a 1-octet field which has two
                         possible values:
                              1      AS_SET: unordered set of ASs a
                                          route in the UPDATE message
                                          has traversed
                              2      AS_SEQUENCE: ordered set of ASs
                                          a route in the UPDATE message
                                          has traversed.

                          The length is a 1-octet field containing the
                          number of ASs in the value field.

                          The value field contains one or more AS
                          numbers, each AS is represented in the octet
                          string as a pair of octets according to the
                          following algorithm:

                               first-byte-of-pair = ASNumber / 256;
                               second-byte-of-pair = ASNumber & 255;"
                    ::= { bgp4PathAttrEntry 5 }

               bgp4PathAttrNextHop OBJECT-TYPE
                    SYNTAX IpAddress
                    ACCESS read-only
                    STATUS mandatory
                    DESCRIPTION
                         "The address of the border router that should
                         be used for the destination network."
                    ::= { bgp4PathAttrEntry 6 }

                bgp4PathAttrMultiExitDisc OBJECT-TYPE
                    SYNTAX INTEGER (0..255)
                    ACCESS read-only





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                    STATUS mandatory
                    DESCRIPTION
                         "This metric is used to discriminate between
                          multiple exit points to an adjacent autonomous
                          system."
                    ::= { bgp4PathAttrEntry 7 }

               bgp4PathAttrLocalPref OBJECT-TYPE
                    SYNTAX INTEGER (0..255)
                    ACCESS read-only
                    STATUS mandatory
                    DESCRIPTION
                         "The originating BGP4 speaker's degree of
                          preference for an advertised route."
                    ::= { bgp4PathAttrEntry 8 }

               bgp4PathAttrAtomicAggregate OBJECT-TYPE
                    SYNTAX INTEGER {
                         less-specific-route-not-selected(1),
                         less-specific-route-selected(2)
                    }
                    ACCESS read-only
                    STATUS mandatory
                    DESCRIPTION
                         "Whether or not the local system has selected
                          a less specific route without selecting a
                          more specific route."
                    ::= { bgp4PathAttrEntry 9 }

               bgp4PathAttrAggregator OBJECT-TYPE
                    SYNTAX INTEGER (0..65535)
                    ACCESS read-only
                    STATUS mandatory
                    DESCRIPTION
                        "The AS number of the last BGP4 speaker that
                         performed route aggregation. "
                    ::= { bgp4PathAttrEntry 10 }



               bgpEstablished TRAP-TYPE
                    ENTERPRISE { bgp }
                    VARIABLES  { bgpPeerRemoteAddr,
                              bgpPeerLastError,
                              bgpPeerState }





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                    DESCRIPTION
                         "The BGP Established event is generated when
                         the BGP FSM enters the ESTABLISHED state. "
                    ::= 1

               bgpBackwardTransition TRAP-TYPE
                    ENTERPRISE { bgp }
                    VARIABLES  { bgpPeerRemoteAddr,
                              bgpPeerLastError,
                              bgpPeerState }
                    DESCRIPTION
                         "The BGPBackwardTransition Event is generated
                         when the BGP FSM moves from a higher numbered
                         state to a lower numbered state."
                    ::= 2
               END


6.  Acknowledgements

   We would like to acknowledge the assistance of all the members of the
   Interconnectivity Working Group, and particularly the following
   individuals:

                Yakov Rekhter, IBM
                Rob Coltun, University of Maryland
                Guy Almes, ANS
                Jeff Honig, Cornell Theory Center
                Marshall T. Rose, PSI, Inc.
                Dennis Ferguson, ANS
                Mike Mathis, PSC
                John Krawczyk, Wellfleet Communications Inc.
                Curtis Villamizar, ANS


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





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       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.

   [11] Rekhter, Y., and Li, T., "A Border Gateway Protocol 4 (BGP-4)",
        Internet Draft, T.J. Watson Research Center, IBM Corp.,
        cisco Systems, June 1992.

   [12] Rekhter, Y., and P. Gross, Editors, "Application of the Border
        Gateway Protocol in the Internet", RFC 1268, T.J. Watson
        Research Center, IBM Corp., ANS, October 1991.









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8.  Security Considerations

   Security issues are not discussed in this memo.



Authors' Addresses

   Steven Willis
   Wellfleet Communications Inc.
   15 Crosby Drive
   Bedford, MA 01730

   Phone: (617) 275-2400
   Email: swillis@wellfleet.com


   John Burruss
   Wellfleet Communications Inc.
   15 Crosby Drive
   Bedford, MA 01730

   Phone: (617) 275-2400
   Email: jburruss@wellfleet.com


   John Chu
   IBM Corp.
   P.O.Box 218
   Yorktown Heights, NY 10598

   Phone: (914) 945-3156
   Email: jychu@watson.ibm.com

















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