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Versions: 00 01 02 03 04 05 06 07 08 09 10 11 12 13 14 15 16 17 RFC 6396

Network Working Group                                           L. Blunk
Internet-Draft                                                  M. Karir
Intended status: Standards Track                           Merit Network
Expires: September 6, 2007                                   C. Labovitz
                                                          Arbor Networks
                                                           March 5, 2007


                 MRT routing information export format
                       draft-ietf-grow-mrt-04.txt

Status of this Memo

   By submitting this Internet-Draft, each author represents that any
   applicable patent or other IPR claims of which he or she is aware
   have been or will be disclosed, and any of which he or she becomes
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   This Internet-Draft will expire on September 6, 2007.

Copyright Notice

   Copyright (C) The IETF Trust (2007).












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Abstract

   This document describes the MRT format for routing information
   export.  This format was developed in concert with the Multi-threaded
   Routing Toolkit (MRT) from whence the format takes it name.  The
   format can be used to export routing protocol messages, state
   changes, and routing information base contents.


Table of Contents

   1.  Requirements notation  . . . . . . . . . . . . . . . . . . . .  4
   2.  Introduction . . . . . . . . . . . . . . . . . . . . . . . . .  5
   3.  Basic MRT Format . . . . . . . . . . . . . . . . . . . . . . .  6
   4.  MRT Control Types  . . . . . . . . . . . . . . . . . . . . . .  8
     4.1.  NULL Type  . . . . . . . . . . . . . . . . . . . . . . . .  8
     4.2.  START Type . . . . . . . . . . . . . . . . . . . . . . . .  8
     4.3.  DIE Type . . . . . . . . . . . . . . . . . . . . . . . . .  8
     4.4.  I_AM_DEAD Type . . . . . . . . . . . . . . . . . . . . . .  8
     4.5.  PEER_DOWN Type . . . . . . . . . . . . . . . . . . . . . .  8
   5.  MRT Routing Information Types  . . . . . . . . . . . . . . . .  9
     5.1.  BGP Type . . . . . . . . . . . . . . . . . . . . . . . . .  9
       5.1.1.  BGP_NULL Subtype . . . . . . . . . . . . . . . . . . .  9
       5.1.2.  BGP_UPDATE Subtype . . . . . . . . . . . . . . . . . . 10
       5.1.3.  BGP_PREF_UPDATE Subtype  . . . . . . . . . . . . . . . 10
       5.1.4.  BGP_STATE_CHANGE Subtype . . . . . . . . . . . . . . . 10
       5.1.5.  BGP_SYNC Subtype . . . . . . . . . . . . . . . . . . . 11
       5.1.6.  BGP_OPEN Subtype . . . . . . . . . . . . . . . . . . . 11
       5.1.7.  BGP_NOTIFY Subtype . . . . . . . . . . . . . . . . . . 11
       5.1.8.  BGP_KEEPALIVE Subtype  . . . . . . . . . . . . . . . . 11
     5.2.  RIP Type . . . . . . . . . . . . . . . . . . . . . . . . . 11
     5.3.  IDRP Type  . . . . . . . . . . . . . . . . . . . . . . . . 12
     5.4.  RIPNG Type . . . . . . . . . . . . . . . . . . . . . . . . 12
     5.5.  BGP4PLUS and BGP4PLUS_01 Types . . . . . . . . . . . . . . 12
     5.6.  OSPF Type  . . . . . . . . . . . . . . . . . . . . . . . . 13
     5.7.  TABLE_DUMP Type  . . . . . . . . . . . . . . . . . . . . . 13
     5.8.  TABLE_DUMP_V2 Type . . . . . . . . . . . . . . . . . . . . 15
     5.9.  BGP4MP Type  . . . . . . . . . . . . . . . . . . . . . . . 17
       5.9.1.  BGP4MP_STATE_CHANGE Subtype  . . . . . . . . . . . . . 18
       5.9.2.  BGP4MP_MESSAGE Subtype . . . . . . . . . . . . . . . . 18
       5.9.3.  BGP4MP_ENTRY Subtype . . . . . . . . . . . . . . . . . 19
       5.9.4.  BGP4MP_SNAPSHOT Subtype  . . . . . . . . . . . . . . . 20
       5.9.5.  BGP4MP_MESSAGE_AS4 Subtype . . . . . . . . . . . . . . 20
     5.10. BGP4MP_ET  . . . . . . . . . . . . . . . . . . . . . . . . 21
     5.11. ISIS Type  . . . . . . . . . . . . . . . . . . . . . . . . 21
     5.12. ISIS_ET Type . . . . . . . . . . . . . . . . . . . . . . . 22
     5.13. OSPFv3 Type  . . . . . . . . . . . . . . . . . . . . . . . 22
     5.14. OSPFv3_ET Type . . . . . . . . . . . . . . . . . . . . . . 22



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   6.  IANA Considerations  . . . . . . . . . . . . . . . . . . . . . 23
     6.1.  Type Codes . . . . . . . . . . . . . . . . . . . . . . . . 23
     6.2.  Subtype Codes  . . . . . . . . . . . . . . . . . . . . . . 23
   7.  Security Considerations  . . . . . . . . . . . . . . . . . . . 24
   8.  References . . . . . . . . . . . . . . . . . . . . . . . . . . 25
     8.1.  Normative References . . . . . . . . . . . . . . . . . . . 25
     8.2.  Informative References . . . . . . . . . . . . . . . . . . 25
   Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 26
   Intellectual Property and Copyright Statements . . . . . . . . . . 27










































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1.  Requirements notation

   The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
   "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
   document are to be interpreted as described in [RFC2119].














































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2.  Introduction

   Researchers and engineers often wish to analyze network behavior by
   studying routing protocol transactions and routing information base
   snapshots.  To this end, the MRT format was developed to encapsulate,
   export, and archive this information in a standardized data
   representation.  The BGP routing protocol, in particular, has been
   the subject of extensive study and analysis which has been
   significantly aided by the availability of the MRT format.  The MRT
   format was initially defined in the MRT Programmer's Guide [MRT PROG
   GUIDE].

   This memo serves to document the MRT format as currently implemented
   in publicly available software.  The format has been extended since
   it's original introduction in the MRT toolset and these extensions
   are also included in this memo.  Further extensions may be introduced
   at a later date through additional definitions of the MRT Type field
   and Subtype fields.

































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3.  Basic MRT Format

   All MRT format messages have a common header which includes a
   timestamp, Type, Subtype, and length field.  The header is followed
   by a message field.  The basic MRT format is illustrated below.

        0                   1                   2                   3
        0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                           Timestamp                           |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |             Type              |            Subtype            |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                             Length                            |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                      Message... (variable)
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

   Header Field Descriptions:


      Timestamp:

         Time in seconds since 1 January 1970 00:00:00 UTC


      Type:

         A 2-octet field that indicates the Type of information
         contained in the message field.  Types 1 through 5 are used for
         MRT control information while Types 6 and higher are used for
         routing information.


      Subtype:

         A 2-octet message Subtype field


      Length:

         A 4-octet message length field.  The length does not include
         the header.


      Message:





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         A variable length message.  The contents of this field are
         context dependent on the Type and Subtype fields.

















































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4.  MRT Control Types

   The MRT format defines five Control Type messages.  These messages
   are using to relay the current state of MRT message source.  The
   message field MAY contain an OPTIONAL ASCII text string for
   diagnostic purposes.  These control messages are unidirectional in
   nature and there is no form of an acknowledgment or response from the
   receiver to the sender.  The Subtype field is unused for these Types
   and SHOULD be set to 0.

   The MRT Control Types are defined below:

       0    NULL
       1    START
       2    DIE
       3    I_AM_DEAD
       4    PEER_DOWN

4.1.  NULL Type

   The NULL Type message causes no operation, A sender may wish to send
   these for synchronization or keep-alive purposes.

4.2.  START Type

   The START Type indicates a sender is about to begin sending MRT
   messages

4.3.  DIE Type

   A DIE Type signals that the receiver should shut down.

4.4.  I_AM_DEAD Type

   A I_AM_DEAD indicates that the sender is shutting down.

4.5.  PEER_DOWN Type

   A PEER_DOWN is sent when the sender's peer is down.  In practice, a
   sender will likely have multiple peers.  It is RECOMMENDED that the
   sender use the Message field to convey the IP address of the peer
   represented in US-ASCII.









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5.  MRT Routing Information Types

   The following Types are currently defined for the MRT format.  Types
   5-12 were defined in the initial MRT Toolkit package.  The BGP4MP
   Type, number 16, was initially defined in the Zebra routing software
   package.  The ISIS Type was initially defined in the Sprint Labs
   Python Routing Toolkit (PyRT).

       5    BGP          *DEPRECATED*
       6    RIP
       7    IDRP         *DEPRECATED*
       8    RIPNG
       9    BGP4PLUS     *DEPRECATED*
       10   BGP4PLUS_01  *DEPRECATED*
       11   OSPF
       12   TABLE_DUMP
       13   TABLE_DUMP_V2
       16   BGP4MP
       17   BGP4MP_ET
       32   ISIS
       33   ISIS_ET
       48   OSPFv3
       49   OSPFv3_ET

5.1.  BGP Type

   The BGP Type indicates the Message field contains BGP routing
   information.  The BGP routing protocol is defined in RFC 4271
   [RFC4271].  The information in the message is dependent on the
   Subtype value.  The BGP Type and all associated Subtypes are
   considered to be DEPRECATED by the BGP4MP Type.

   The following BGP Subtypes are defined for the MRT BGP Type.

       0    BGP_NULL
       1    BGP_UPDATE
       2    BGP_PREF_UPDATE
       3    BGP_STATE_CHANGE
       4    BGP_SYNC
       5    BGP_OPEN
       6    BGP_NOTIFY
       7    BGP_KEEPALIVE

5.1.1.  BGP_NULL Subtype

   The BGP_NULL Subtype is a reserved Subtype.





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5.1.2.  BGP_UPDATE Subtype

   The BGP_UPDATE Subtype is used to encode BGP UPDATE messages.  The
   format of the MRT Message field for this Subtype is as follows:

        0                   1                   2                   3
        0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |        Source AS number       |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                        Source IP address                      |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |    Destination AS number      |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                      Destination IP address                   |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                    BGP UPDATE Contents (variable)
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

   The BGP UPDATE contents include the entire BGP UPDATE message which
   follows the BGP Message Header.  The BGP Message Header itself is not
   included.

5.1.3.  BGP_PREF_UPDATE Subtype

   The BGP_PREF_UPDATE Subtype is not defined.

5.1.4.  BGP_STATE_CHANGE Subtype

   The BGP_STATE_CHANGE Subtype is used to record changes in the BGP
   finite state machine.  These FSM states and their numeric encodings
   are defined in RFC 4271 [RFC4271], Appendix 1.  Both the old state
   value and the new state value are encoded as 2-octet numbers.  The
   format of the MRT Message field is as follows:

        0                   1                   2                   3
        0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |        Source AS number       |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                       Source IP address                       |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |            Old State          |          New State            |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+







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5.1.5.  BGP_SYNC Subtype

   The BGP_SYNC Subtype is used to indicate a File Name where BGP Table
   Dump messages should be recorded.  The View # corresponds to the View
   # provided in the TABLE_DUMP Type messages.  The following format
   applies to this Subtype:

        0                   1                   2                   3
        0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |        View #                 |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |            File Name... (variable)
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

   The File Name is terminated with a NULL (0) character.

5.1.6.  BGP_OPEN Subtype

   The BGP_OPEN Subtype is used to encode BGP OPEN messages.  The format
   of the MRT Message field for this Subtype is the same as the
   BGP_UPDATE, however, the last field contains the contents of the BGP
   OPEN message.

5.1.7.  BGP_NOTIFY Subtype

   The BGP_NOTIFY Subtype is used to encode BGP NOTIFICATION messages.
   The format of the MRT Message field for this Subtype is the same as
   the BGP_UPDATE, however, the last field contains the contents of the
   BGP NOTIFICATION message.

5.1.8.  BGP_KEEPALIVE Subtype

   The BGP_KEEPALIVE Subtype is used to encode BGP KEEPALIVE messages.
   The format of the MRT Message field for this Subtype is the same as
   the BGP_UPDATE, however, the last field contains no information.

5.2.  RIP Type

   The RIP Type is used to export RIP protocol packets as defined in RFC
   1058 [RFC1058].  The Subtype field is currently reserved for this
   Type and SHOULD be set to 0.

   The format of the MRT Message field for the RIP Type is as follows:







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        0                   1                   2                   3
        0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                        Source IP address                      |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                      Destination IP address                   |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                    RIP Message Contents (variable)
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

5.3.  IDRP Type

   The IDRP Type is used to export Inter-Domain-Routing Protocol (IDRP)
   protocol information as defined in the ISO/IEC 10747 standard.  The
   Subtype field is unused.  This Type is deprecated due to lack of
   deployment of IDRP.

5.4.  RIPNG Type

   The RIPNG Type is used to export RIPNG protocol packets as defined in
   RFC 2080 [RFC2080].  The Subtype field is currently reserved for this
   Type and SHOULD be set to 0.

   The format of the MRT Message field for the RIPNG Type is as follows:

        0                   1                   2                   3
        0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                        Source IP address                      |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                      Destination IP address                   |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                  RIPNG Message Contents (variable)
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

5.5.  BGP4PLUS and BGP4PLUS_01 Types

   The BGP4PLUS and BGP4PLUS_01 Types were defined to support IPv6 BGP
   routing information.  The BGP4PLUS Type was specified based on the
   initial Internet Draft for Multiprotocol Extensions to BGP-4.  The
   BGP4PLUS_01 Type was specified to correspond to the -01 revision of
   this Internet Draft.  The two Types share the same definitions in
   terms of their MRT format specifications.

   The Subtype field definitions are shared with the BGP Type, however,
   the address fields in the BGP_UPDATE, BGP_OPEN, BGP_NOTIFY,
   BGP_KEEPALIVE, and BGP_STATE_CHANGE Subtype messages are extended to
   16 octets for IPv6 addresses.  As with the BGP Type, the BGP4PLUS and



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   BGP4PLUS_01 Types are deprecated as they superseded by the BGP4MP
   Type.

5.6.  OSPF Type

   This Type supports the OSPF Protocol as defined in RFC 2328
   [RFC2328].  The Subtype field may contain two possible values:

       0    OSPF_STATE_CHANGE
       1    OSPF_LSA_UPDATE

   The format of the MRT Message field for the OSPF Type is as follows:

        0                   1                   2                   3
        0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                        Source IP address                      |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                      Destination IP address                   |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                  OSPF Message Contents (variable)
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

5.7.  TABLE_DUMP Type

   The TABLE_DUMP Type is used to encode the contents of a BGP Routing
   Information Base (RIB).  Each RIB entry is encoded in a distinct
   sequential MRT record.  The Subtype field is used to encode whether
   the RIB entry contains IPv4 or IPv6 addresses.  There are currently
   two possible values for the Subtype as shown below.

       1    AFI_IPv4
       2    AFI_IPv6

   The format of the TABLE_DUMP Type is illustrated below.
















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        0                   1                   2                   3
        0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |           View #              |       Sequence number         |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                        Prefix (variable)                      |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       | Prefix Length |    Status     |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                         Originated Time                       |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                    Peer IP address (variable)                 |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |           Peer AS             |       Attribute Length        |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                   BGP Attribute... (variable)
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

   The View field is normally 0 and is intended for cases where an
   implementation may have multiple RIB views (such as a route server).
   The Sequence field is a simple incremental counter for each RIB
   entry.  A typical RIB dump will exceed the 16-bit bounds of this
   counter and implementation should simply wrap back to zero and
   continue incrementing the counter in such cases.

   The Prefix field contains the IP address of a particular routing RIB
   entry.  The size of this field is dependent on the value of the
   Subtype for this message.  For AFI_IPv4, this field is 4 octets, for
   AFI_IPv6, it is 16 octets in length.  The Prefix Length field
   indicates the length in bits of the prefix mask for the preceding
   Prefix field.

   The Status octet is not used in the TABLE_DUMP Type and SHOULD be set
   to 1.

   The Originated Time contains the 4-octet time at which this prefix
   was heard.  The value represents the time in seconds since 1 January
   1970 00:00:00 UTC.

   The Peer IP field is the IP address of the peer which provided the
   update for this RIB entry.  As with the Prefix field, the size of
   this field is dependent on the Subtype.  AFI_IPv4 indicates a 4 octet
   field and an IPv4 address, while a Subtype of AFI_IPv6 requires a 16
   octet field and an IPv6 address.  The Peer AS field contains the AS
   number of the peer.

   Attribute length is the length of Attribute field and is 2-octets.
   The Attribute field contains the attribute information for the RIB



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   entry.

5.8.  TABLE_DUMP_V2 Type

   The TABLE_DUMP_V2 type updates the TABLE_DUMP type to include 32-bit
   ASN support and full support for BGP Multiprotocol extensions.  It
   also improves upon the space efficiency of the TABLE_DUMP type by
   employing an index table for peers and permitting a single MRT record
   per NLRI entry.  The following subtypes are used with the
   TABLE_DUMP_V2 type.

       1    INDEX_TABLE
       2    RIB_IPV4_UNICAST
       3    RIB_IPV4_MULTICAST
       4    RIB_IPV6_UNICAST
       5    RIB_IPV6_MULTICAST
       6    RIB_GENERIC

   An initial INDEX_TABLE MRT record provides the BGP ID of the
   collector, an optional view name, and a list of indexed peers.
   Following the INDEX_TABLE MRT record, a series of MRT records are
   used to encode RIB table entries.  The header of the INDEX_TABLE
   Subtype is shown below.  The View Name is optional and if not
   present, the View Name Length MUST be set to 0.

        0                   1                   2                   3
        0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                      Collector BGP ID                         |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |       View Name Length        |     View Name (variable)      |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |          Peer Count           |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

   The Peer Type field is a bit field which encodes the type of the AS
   and IP address as follows:

      Bit 0 - unset for IPv4 Peer IP address, set of IPv6
      Bit 1 - unset when Peer AS field is 16 bits, set when it's 32 bits











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        0                   1                   2                   3
        0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |   Peer Type   |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                         Peer BGP ID                           |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                   Peer IP address (variable)                  |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                        Peer AS (variable)                     |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

   The Peer Type, Peer BGP ID, Peer IP, and Peer AS fields are repeated
   as indicated by the Peer Count field.  The position of the Peer in
   the INDEX_TABLE is used as an index in the subsequent TABLE_DUMP_V2
   MRT records.  The index number begins with 0.

   The records which follow the INDEX_TABLE record constitute the RIB
   entries and include a header which specify a sequence number, NLRI,
   and a count of the number of RIB entries which follow.

   The RIB_IPV4_UNICAST, RIB_IPV4_MULTICAST, RIB_IPV6_UNICAST, and
   RIB_IPV6_MULTICAST headers are shown below.  The Prefix Length and
   Prefix fields are encoded in the same manner as the BGP NLRI encoding
   for IPV4 and IPV6 prefixes.  Namely, the Prefix field contains
   address prefixes followed by enough trailing bits to make the end of
   the field fall on an octet boundary.  Note that the value of trailing
   bits is irrelevant.

        0                   1                   2                   3
        0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                         Sequence number                       |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       | Prefix Length |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                        Prefix (variable)                      |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |         Entry Count           |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

   The RIB_GENERIC header is shown below.  It includes Address Family
   Identifier (AFI), Subsequent AFI and a single NLRI entry.  The NLRI
   information is specific to the AFI and SAFI values.  An
   implementation which does not recognize particular AFI and SAFI
   values SHOULD discard the remainder of the MRT record.





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        0                   1                   2                   3
        0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                         Sequence number                       |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |    Address Family Identifier  |Subsequent AFI |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |     Network Layer Reachability Information (variable)         |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |         Entry Count           |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

   The RIB entry headers are followed by a series of RIB entries which
   are repeated Entry Count times.  These entries share a common format
   as shown below.  They include a Peer Index from the INDEX_TABLE MRT
   record, an originated time for the RIB entry, and the BGP path
   attribute length and attributes encoded as provided in a BGP Update
   message.

        0                   1                   2                   3
        0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |         Peer Index            |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                         Originated Time                       |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |      Attribute Length         |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                    BGP Attributes... (variable)
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

   There is one exception to the encoding of BGP attributes for the BGP
   MP_REACH_NLRI attribute (BGP Type Code 14) [RFC 4760].  Since the
   AFI, SAFI, and NLRI information is already encoded in the
   MULTIPROTOCOL header, only the Next Hop Address Length and Next Hop
   Address fields are included.  The Reserved field is omitted.  The
   attribute length is also adjusted to reflect only the length of the
   Next Hop Address Length and Next Hop Address fields.

5.9.  BGP4MP Type

   This Type was initially defined in the Zebra software package for the
   BGP protocol with multiprotocol extension support as defined by RFC
   4760 [RFC4760].  It supersedes the BGP, BGP4PLUS, BGP4PLUS_01 Types.
   The BGP4MP Type has four Subtypes which are defined as follows:






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       0    BGP4MP_STATE_CHANGE
       1    BGP4MP_MESSAGE
       2    BGP4MP_ENTRY                  *DEPRECATED*
       3    BGP4MP_SNAPSHOT
       4    BGP4MP_STATE_CHANGE_AS4
       5    BGP4MP_MESSAGE_AS4

5.9.1.  BGP4MP_STATE_CHANGE Subtype

   This record is used to encode state changes in the BGP finite state
   machine.  As with the BGP_STATE_CHANGE Subtype, the BGP FSM states
   are encoded in the Old State and New State fields to indicate the
   previous and current state.  The format is illustrated below:

        0                   1                   2                   3
        0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |        Source AS number       |     Destination AS number     |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |        Interface Index        |        Address Family         |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                     Source IP address (variable)              |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                   Destination IP address (variable)           |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |            Old State          |          New State            |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

   While BGP4MP_STATE_CHANGE message is similar to the BGP_STATE_CHANGE
   message, it also includes interface index and Address Family fields.
   As with the BGP_STATE_CHANGE message, the FSM states and their
   numeric encodings are defined in RFC 4271 [RFC4271], Appendix 1.  The
   interface index provides the interface number of the peering session.
   The index value is OPTIONAL and MAY be zero if unknown or
   unsupported.  The Address Family indicates what types of addresses
   are in the the address fields.  At present, the following AFI Types
   are supported:

       1    AFI_IPv4
       2    AFI_IPv6

5.9.2.  BGP4MP_MESSAGE Subtype

   This Subtype is used to encode BGP Messages.  It is similar to the
   BGP_UPDATE Subtype, except that is can be used to encode any Type of
   message (not just BGP UPDATES).  In order to determine the BGP
   message Type, the entire BGP message, including the BGP header, is
   included in the BGP Message field.  The BGP4MP_MESSAGE fields are



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   shown below:

        0                   1                   2                   3
        0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |        Source AS number       |     Destination AS number     |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |        Interface Index        |        Address Family         |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                     Source IP address (variable)              |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                   Destination IP address (variable)           |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                    BGP Message... (variable)
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

   The interface index provides the interface number of the peering
   session.  The index value is OPTIONAL and MAY be zero if unknown or
   unsupported.  The Address Family indicates what types of addresses
   are in the the subsequent address fields.  At present, the following
   AFI Types are supported:

       1    AFI_IPv4
       2    AFI_IPv6

   Note that the Address Family value only applies to the IP addresses
   contained in the MRT header.  The BGP4MP_MESSAGE Subtype is otherwise
   transparent to the contents of the actual message which may contain
   any valid AFI/SAFI values.  Only one BGP message may be encoded in
   the BGP4MP_MESSAGE Subtype.

5.9.3.  BGP4MP_ENTRY Subtype

   This Subtype is similar to the TABLE_DUMP Type and is used to record
   RIB table entries.  It extends the TABLE_DUMP Type to include true
   multiprotocol support.  However, this type does not support 32-bit AS
   numbers and has not been widely implemented.  This type is deprecated
   in favor of the TABLE_DUMP_V2 which includes 32-bit AS number support
   and a more compact format.












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        0                   1                   2                   3
        0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |        Source AS number       |     Destination AS number     |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |        Interface Index        |        Address Family         |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                     Source IP address (variable)              |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                   Destination IP address (variable)           |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |           View #              |             Status            |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                        Time last change                       |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |        Address Family         |    SAFI       | Next-Hop-Len  |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                     Next Hop Address (variable)               |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       | Prefix Length  |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                     Address Prefix (variable)                 |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |       Attribute Length        |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                    BGP Attribute... (variable)
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

5.9.4.  BGP4MP_SNAPSHOT Subtype

   This Subtype is used to indicate a filename containing BGP4MP_ENTRY
   records.  It is similar to the BGP_SYNC message Subtype and shares
   the same fields.

        0                   1                   2                   3
        0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |        View #                 |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |            File Name... (variable)
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

5.9.5.  BGP4MP_MESSAGE_AS4 Subtype

   This Subtype updates the BGP4MP_MESSAGE Subtype to support 32BIT
   Autonomous System numbers.  The BGP4MP_MESSAGE_AS4 fields are shown
   below:




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        0                   1                   2                   3
        0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                        Source AS number                       |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                     Destination AS number                     |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |        Interface Index        |        Address Family         |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                     Source IP address (variable)              |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                   Destination IP address (variable)           |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                    BGP Message... (variable)
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

5.10.  BGP4MP_ET

   This Type was initially defined in the Sprint Labs Python Routing
   Toolkit (PyRT).  It extends the header field of the BGP4MP Type to
   include a 32-bit microsecond timestamp field.  The Subtypes and other
   field definitions remain as defined for the BGP4MP Type.  The 32-bit
   microsecond timestamp immediately follows the length field in the
   BGP4MP Type and precedes all other fields in the message.  The header
   modification is illustrated below.

        0                   1                   2                   3
        0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                           Timestamp                           |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |             Type              |            Subtype            |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                             Length                            |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                      microsecond timestamp                    |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                      Message... (variable)
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

5.11.  ISIS Type

   This Type was initially defined in the Sprint Labs Python Routing and
   supports the IS-IS routing protocol as defined in RFC 1195 [RFC1195].
   There is no Type specific header for the ISIS Type.  The Subtype code
   for this Type is undefined.  The ISIS PDU directly follows the MRT
   common header fields.




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5.12.  ISIS_ET Type

   The ISIS_ET Type extends the the ISIS Type to support microsecond
   timestamps.  As with the BGP4MP_ET Type, a 32-bit microsecond
   timestamp field is appended to the MRT common header after the length
   field.  The ISIS_ET Type is otherwise identical to the ISIS Type.

5.13.  OSPFv3 Type

   The OSPFv3 Type extends the original OSPF Type to support IPv6
   addresses for the OSPFv3 protocol as defined in RFC 2740 [RFC2740].
   The format of the MRT Message field for the OSPFv3 Type is as
   follows:

        0                   1                   2                   3
        0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |        Address Family         |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                     Source IP address (variable)              |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                   Destination IP address (variable)           |
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
       |                  OSPF Message Contents (variable)
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

5.14.  OSPFv3_ET Type

   The OSPFv3_ET Type extends the the OSPFv3 Type to support microsecond
   timestamps.  As with the BGP4MP_ET Type, a 32-bit microsecond
   timestamp field is appended to the MRT common header after the length
   field.  The OSPFv3_ET Type is otherwise identical to the OSPFv3 Type.



















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6.  IANA Considerations

   This section provides guidance to the Internet Assigned Numbers
   Authority (IANA) regarding registration of values related to the MRT
   specification, in accordance with BCP 26, RFC 2434 [RFC2434].

   There are two name spaces in MRT that require registration: Type
   Codes and Subtype Codes.

   MRT is not intended as a general-purpose specification for protocol
   information export, and allocations should not be made for purposes
   unrelated to routing protocol information export.

   The following policies are used here with the meanings defined in BCP
   26: "Specification Required", "IETF Consensus".

6.1.  Type Codes

   Type Codes have a range from 0 to 65535, of which 0-64 have been
   allocated.  New Type Codes MUST be allocated starting at 65.  Type
   Codes 65 - 32767 are to be assigned by IETF Consensus.  Type Codes
   32768 - 65535 are assigned based on Specification Required.

6.2.  Subtype Codes

   Subtype Codes have a range from 0 to 65535.  Subtype definitions are
   specific to a particular Type Code definition.  New Subtype Code
   definition must reference an existing Type Code to which the Subtype
   belongs.  As Subtype Codes are specific to Type Codes, new numbers
   must be unique for the particular Type Code to which the Subtype
   applies.  Subtype Codes specific to the Type Codes 0 - 32767 are
   assigned by IETF Consensus.  Suptype Codes specific to Type Codes
   32768 - 65535 are assigned based on Specification Required.


















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7.  Security Considerations

   The MRT Format utilizes a structure which can store routing protocol
   information data.  The fields defined in the MRT specification are of
   a descriptive nature and provide information that is useful to
   facilitate the analysis of routing data.  As such, the fields
   currently defined in the MRT specification do not in themselves
   create additional security risks, since the fields are not used to
   induce any particular behavior by the recipient application.










































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8.  References

8.1.  Normative References

   [RFC1058]  Hedrick, C., "Routing Information Protocol", RFC 1058,
              June 1988.

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

   [RFC2080]  Malkin, G. and R. Minnear, "RIPng for IPv6", RFC 2080,
              January 1997.

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

   [RFC2328]  Moy, J., "OSPF Version 2", STD 54, RFC 2328, April 1998.

   [RFC2434]  Narten, T. and H. Alvestrand, "Guidelines for Writing an
              IANA Considerations Section in RFCs", BCP 26, RFC 2434,
              October 1998.

   [RFC2740]  Coltun, R., Ferguson, D., and J. Moy, "OSPF for IPv6",
              RFC 2740, December 1999.

   [RFC4271]  Rekhter, Y., Li, T., and S. Hares, "A Border Gateway
              Protocol 4 (BGP-4)", RFC 4271, January 2006.

   [RFC4760]  Bates, T., Chandra, R., Katz, D., and Y. Rekhter,
              "Multiprotocol Extensions for BGP-4", RFC 4760,
              January 2007.

8.2.  Informative References

   [MRT PROG GUIDE]
              Labovitz, C., "MRT Programmer's Guide", November 1999,
              <http://www.merit.edu/nrd/resources/mrtprogrammer.pdf>.














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Authors' Addresses

   Larry Blunk
   Merit Network

   Email: ljb@merit.edu


   Manish Karir
   Merit Network

   Email: mkarir@merit.edu


   Craig Labovitz
   Arbor Networks

   Email: labovit@arbor.net

































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Full Copyright Statement

   Copyright (C) The IETF Trust (2007).

   This document is subject to the rights, licenses and restrictions
   contained in BCP 78, and except as set forth therein, the authors
   retain all their rights.

   This document and the information contained herein are provided on an
   "AS IS" basis and THE CONTRIBUTOR, THE ORGANIZATION HE/SHE REPRESENTS
   OR IS SPONSORED BY (IF ANY), THE INTERNET SOCIETY, THE IETF TRUST AND
   THE INTERNET ENGINEERING TASK FORCE DISCLAIM ALL WARRANTIES, EXPRESS
   OR IMPLIED, INCLUDING BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF
   THE INFORMATION HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED
   WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.


Intellectual Property

   The IETF takes no position regarding the validity or scope of any
   Intellectual Property Rights or other rights that might be claimed to
   pertain to the implementation or use of the technology described in
   this document or the extent to which any license under such rights
   might or might not be available; nor does it represent that it has
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   on the procedures with respect to rights in RFC documents can be
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   Copies of IPR disclosures made to the IETF Secretariat and any
   assurances of licenses to be made available, or the result of an
   attempt made to obtain a general license or permission for the use of
   such proprietary rights by implementers or users of this
   specification can be obtained from the IETF on-line IPR repository at
   http://www.ietf.org/ipr.

   The IETF invites any interested party to bring to its attention any
   copyrights, patents or patent applications, or other proprietary
   rights that may cover technology that may be required to implement
   this standard.  Please address the information to the IETF at
   ietf-ipr@ietf.org.


Acknowledgment

   Funding for the RFC Editor function is provided by the IETF
   Administrative Support Activity (IASA).





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