MRT routing information export format

MRT routing information export format Merit Network

ljb@merit.edu

Merit Network

mkarir@merit.edu

Arbor Networks

labovit@arbor.net

Operations Network Working Group MRT 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.

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 .

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. 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. Fields which contain multi-byte numeric values are encoded in network byte order from most significant byte to least significant byte. Fields which contain routing message fields are encoded in the same order as they appear in the packet contents.

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 MRT common header 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 0 through 4 are informational messages pertaining to the state of an MRT collector, while Types 5 and higher are used to convey routing information. Subtype: A 2-octet field that is used to further distinguish message information within a particular message Type. Length: A 4-octet message length field. The length field contains the number of bytes within the message. The length field does not include the length of the MRT common header. Message: A variable length message. The contents of this field are context dependent upon the Type and Subtype fields.

The MRT format defines five Informational Type messages. These messages are intended to signal the state of an MRT data collector and do not contain routing information. These messages are OPTIONAL and were largely intended for use when MRT messages are sent over a network to a remote repository store. However, MRT message repository stores have traditionally resided on the same device as the collector and these Informational Types have seen limited implementation. Further, transport mechanisms for MRT messages are considered to be outside the scope of this document. The START and I_AM_DEAD messages MAY be used to provide a time reference when a data collector begins and ends the collection process. The message field MAY contain an OPTIONAL message string for diagnostic purposes. The message string encoding MUST follow the UTF-8 transformation format. The Subtype field is unused for these Types and SHOULD be set to 0. The MRT Informational Types are defined below:

1 START 3 I_AM_DEAD

The START Type indicates a collector is about to begin generating MRT messages.

An I_AM_DEAD MRT message indicates that a collector has shut down and has stopped generating MRT messages.

The following Types are currently defined for the MRT format. Types 11 and 12 were defined in the MRT Toolkit package. The BGP4MP Type, number 16, was initially defined in the Zebra routing software package. The BGP4MP_ET, ISIS, and ISIS_ET Types were initially defined in the Sprint Labs Python Routing Toolkit (PyRT). The OSPFv3 and OSPFv3_ET Types are newly defined types created for the OSPFv3 routing protocol.

11 OSPF 12 TABLE_DUMP 13 TABLE_DUMP_V2 16 BGP4MP 17 BGP4MP_ET 32 ISIS 33 ISIS_ET 48 OSPFv3 49 OSPFv3_ET

This Type supports the OSPF Protocol as defined in RFC 2328. 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 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Remote IP address | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Local IP address | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | OSPF Message Contents (variable) +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

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 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.

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 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 entry.

The TABLE_DUMP_V2 Type updates the TABLE_DUMP Type to include 32BIT 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 PEER_INDEX_TABLE 2 RIB_IPV4_UNICAST 3 RIB_IPV4_MULTICAST 4 RIB_IPV6_UNICAST 5 RIB_IPV6_MULTICAST 6 RIB_GENERIC An initial PEER_INDEX_TABLE MRT record provides the BGP ID of the collector, an optional view name, and a list of indexed peers. Following the PEER_INDEX_TABLE MRT record, a series of MRT records are used to encode RIB table entries. This series of MRT records use subtypes 2-6 and are separate from the PEER_INDEX_TABLE MRT record itself and include full MRT record headers. The header of the PEER_INDEX_TABLE Subtype is shown below. The View Name is optional and, if not present, the View Name Length MUST be set to 0. The View Name encoding MUST follow the UTF-8 transformation format.

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 format of the peer entries is shown below. The PEER_INDEX_TABLE record contains Peer Count peer entries.

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 PEER_INDEX_TABLE is used as an index in the subsequent TABLE_DUMP_V2 MRT records. The index number begins with 0. 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 for IPv6 Bit 1 - unset when Peer AS field is 16 bits, set when it's 32 bits The records which follow the PEER_INDEX_TABLE record constitute the RIB entries and include a header which specifies a sequence number, NLRI, and a count of the number of RIB entries which follow. The format for 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.

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 PEER_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.

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

0 BGP4MP_STATE_CHANGE 1 BGP4MP_MESSAGE 4 BGP4MP_STATE_CHANGE_AS4 5 BGP4MP_MESSAGE_AS4

This record is used to encode state changes in the BGP finite state machine. 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:

1 Idle 2 Connect 3 Active 4 OpenSent 5 OpenConfirm 6 Established The BGP4MP_STATE_CHANGE message also includes interface index and Address Family fields. 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

This Subtype is used to encode BGP Messages. It can be used to encode any Type of BGP message. In order to determine the BGP message Type, the entire BGP message is included in the BGP Message field. This includes 16-octet marker, 2-ocet length, and 1-octet type fields. Note that the BGP4MP_MESSAGE Subtype does not support 32BIT AS numbers. The BGP4MP_MESSAGE_AS4 Subtype updates the BGP4MP_MESSAGE Subtype in order to support these. The BGP4MP_MESSAGE fields are 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 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Peer AS number | Local AS number | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Interface Index | Address Family | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Peer IP address (variable) | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Local 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.

This Subtype updates the BGP4MP_STATE_CHANGE Subtype to support 32BIT Autonomous System numbers. As with the BGP4MP_STATE_CHANGE Subtype, the BGP FSM states are encoded in the Old State and New State fields to indicate the previous and current state. Aside from the extension of the peer and local AS fields to 32 bits, this subtype is otherwise identical to the BGP4MP_STATE_CHANGE Subtype. The BGP4MP_STATE_CHANGE_AS4 fields are 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 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Peer AS number | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Local AS number | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Interface Index | Address Family | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Peer IP address (variable) | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Local IP address (variable) | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Old State | New State | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

This Subtype updates the BGP4MP_MESSAGE Subtype to support 32BIT Autonomous System numbers. The BGP4MP_MESSAGE_AS4 Subtype is otherwise identical to the BGP4MP_MESSAGE Subtype. The BGP4MP_MESSAGE_AS4 fields are 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 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Peer AS number | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Local AS number | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Interface Index | Address Family | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Peer IP address (variable) | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Local IP address (variable) | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | BGP Message... (variable) +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

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

This Type was initially defined in the Sprint Labs Python Routing and supports the IS-IS routing protocol as defined in RFC 1195. 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.

The ISIS_ET Type extends the ISIS Type to support microsecond timestamps. As with the BGP4MP_ET Type, a 32BIT 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.

The OSPFv3 Type extends the original OSPF Type to support IPv6 addresses for the OSPFv3 protocol as defined in RFC 2740. 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 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Remote IP address (variable) | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Local IP address (variable) | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | OSPF Message Contents (variable) +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

The OSPFv3_ET Type extends the OSPFv3 Type to support microsecond timestamps. As with the BGP4MP_ET Type, a 32BIT microsecond timestamp field is appended to the MRT common header after the length field and its length is included in the calculation of the length field value. The OSPFv3_ET Type is otherwise identical to the OSPFv3 Type.

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. 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".

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.

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. Subtype Codes specific to Type Codes 32768 - 65535 are assigned based on Specification Required.

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.

MRT Programmer's Guide Arbor Networks

labovit@arbor.net

This Appendix lists deprecated MRT types. These types are documented for informational purposes only. While documented in some references, they are not known to have been generally implemented.

The deprecated MRT Informational Types are defined below:

0 NULL 2 DIE 4 PEER_DOWN

The NULL Type message causes no operation.

The DIE Type signals a remote MRT repository it should stop accepting messages.

The PEER_DOWN message was intended to indicate that a collector had lost association with a BGP peer. However, the MRT format provides BGP state change message types which duplicate this functionality.

5 BGP 6 RIP 7 IDRP 8 RIPNG 9 BGP4PLUS 10 BGP4PLUS_01

The BGP Type indicates the Message field contains BGP routing information. The BGP routing protocol is defined in RFC 4271. The information in the message is dependent on the Subtype value. The BGP Type and all associated Subtypes below are considered to be deprecated by the BGP4MP Type. The following BGP Subtypes are defined for the MRT BGP Type. As with the BGP Type itself, they are all considered to be deprecated.

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

The BGP_NULL Subtype is a reserved 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 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Peer AS number | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Peer IP address | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Local AS number | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Local 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. The Peer AS number and IP address fields contain the AS number and IP address of the remote system which are generating the BGP UPDATE messages. The Local AS number and IP address fields contain the AS number and IP address of the local collector system which is archiving the messages.

The BGP_PREF_UPDATE Subtype is not defined.

The BGP_STATE_CHANGE Subtype is used to record changes in the BGP finite state machine. These FSM states are defined in RFC 4271, Section 8.2.2. Both the old state value and the new state value are encoded as 2-octet numbers. The state values are defined numerically as follows:

1 Idle 2 Connect 3 Active 4 OpenSent 5 OpenConfirm 6 Established The format of the MRT Message field is as follows:

The BGP_SYNC Subtype was intended to convey a system file name where BGP Table Dump messages should be recorded. The View # was to correspond to the View # provided in the TABLE_DUMP Type messages. There are no known implementations of this subtype and it SHOULD be ignored. 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.

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.

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.

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.

The RIP Type is used to export RIP protocol packets as defined in RFC 1058. 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:

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 IP address | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Local IP address | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | RIP Message Contents (variable) +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

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.

The RIPNG Type is used to export RIPNG protocol packets as defined in RFC 2080. The RIPNG protocol updates the RIP protocol to support IPv6. 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 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | | ~ Peer IPv6 address ~ | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | | ~ Local IPv6 address ~ | | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | RIPNG Message Contents (variable) +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

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

The following two subtypes of the BGP4MP Type are considered to be deprecated.

2 BGP4MP_ENTRY 3 BGP4MP_SNAPSHOT

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 32BIT AS numbers and has not been widely implemented. This Type is deprecated in favor of the TABLE_DUMP_V2 which includes 32BIT AS number support and a more compact format.

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 AS number | Local AS number | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Interface Index | Address Family | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Peer IP address (variable) | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | Local 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) +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

This Subtype was intended to convey a system file name where BGP4MP_ENTRY messages should be recorded. It is similar to the BGP_SYNC message Subtype and is deprecated.