INTERNET DRAFT BGP4-MIB August 2004 Network Working Group Editors of this version: INTERNET DRAFT J. Haas S. Hares NextHop Technologies August 2004 Definitions of Managed Objects for the Fourth Version of Border Gateway Protocol (BGP-4) Status of this Memo This document is an Internet-Draft and is in full conformance with all provisions of Section 10 of RFC 2026. Internet-Drafts are working documents of the Internet Engineering Task Force (IETF), its areas, and its working groups. Note that other groups may also distribute working documents as Internet- Drafts. Internet-Drafts are draft documents valid for a maximum of six months and may be updated, replaced, or obsoleted by other documents at any time. It is inappropriate to use Internet- Drafts as reference material or to cite them other than as "work in progress." The list of current Internet-Drafts can be accessed at http://www.ietf.org/ietf/1id-abstracts. The list of Internet-Draft Shadow Directories can be accessed at http://www.ietf.org/shadow.html. Copyright Notice Copyright (C) The Internet Society (2004). All Rights Reserved. Abstract This memo defines a portion of the Management Information Base (MIB) for use with network management protocols in the Internet community In particular, it describes managed objects used for managing the Border Gateway Protocol Version 4 or lower. The origin of this memo is from RFC 1269 "Definitions of Managed Objects for the Border Gateway Protocol (Version 3)", which was Expires February 2005 [Page 1] INTERNET DRAFT BGP4-MIB August 2004 updated to support BGP-4 in RFC 1657. This memo fixes errors introduced when the MIB module was converted to use the SMIv2 language. This memo also updates references to the current SNMP framework documents. This memo is intended to document deployed implementations of this MIB module in a historical context, provide clarifications of some items and also note errors where the MIB module fails to fully represent the BGP protocol. Work is currently in progress to replace this MIB module with a new one representing the current state of the BGP protocol and its extensions. This document obsoletes RFC 1269 and RFC 1657. Distribution of this memo is unlimited. Please forward comments to idr@ietf.org. Table of Contents 1. Introduction ................................................. 3 2. The Internet-Standard Management Framework ................... 3 3. Overview ..................................................... 3 4. Definitions .................................................. 4 5. Intellectual Property ....................................... 32 6. Security Considerations ..................................... 33 7. Acknowledgements ............................................ 35 8. IANA Considerations ......................................... 36 9. Normative References ........................................ 36 10. Editors' Address ............................................ 36 11. Full Copyright Statement .................................... 37 Expires February 2005 [Page 2] INTERNET DRAFT BGP4-MIB August 2004 1. Introduction This memo defines a portion of the Management Information Base (MIB) for use with network management protocols in the Internet community. In particular, it describes managed objects used for managing the Border Gateway Protocol Version 4 or lower [BGP, BGP4APP]. This memo obsoletes RFC 1657 and RFC 1269. 2. The Internet-Standard Management Framework For a detailed overview of the documents that describe the current Internet-Standard Management Framework, please refer to section 7 of RFC 3410 [RFC3410]. Managed objects are accessed via a virtual information store, termed the Management Information Base or MIB. MIB objects are generally accessed through the Simple Network Management Protocol (SNMP). Objects in the MIB are defined using the mechanisms defined in the Structure of Management Information (SMI). This memo specifies a MIB module that is compliant to the SMIv2, which is described in STD 58, RFC 2578 [RFC2578], STD 58, RFC 2579 [RFC2579] and STD 58, RFC 2580 [RFC2580]. 3. Overview These objects are used to control and manage a BGP-4 implementation. Apart from a few system-wide scalar objects, this MIB is broken into three tables: the BGP Peer Table, the BGP Received Path Attribute Table, and the BGP-4 Received Path Attribute Table. The BGP Peer Table contains information about state and current activity of connections with the BGP peers. The BGP Received Path Attribute Table contains path attributes received from all peers running BGP version 3 or less. The BGP-4 Received Path Attribute Table contains path attributes received from all BGP-4 peers. The actual attributes used in determining a route are a subset of the received attribute tables after local routing policy has been applied. Expires February 2005 [Page 3] INTERNET DRAFT BGP4-MIB August 2004 4. Definitions BGP4-MIB DEFINITIONS ::= BEGIN IMPORTS MODULE-IDENTITY, OBJECT-TYPE, NOTIFICATION-TYPE, IpAddress, Integer32, Counter32, Gauge32, mib-2 FROM SNMPv2-SMI MODULE-COMPLIANCE, OBJECT-GROUP, NOTIFICATION-GROUP FROM SNMPv2-CONF; bgp MODULE-IDENTITY LAST-UPDATED "200408310000Z" ORGANIZATION "IETF IDR Working Group" CONTACT-INFO "E-mail: idr@ietf.org Jeffrey Haas, Susan Hares (Editors) NextHop Technologies 825 Victors Way Suite 100 Ann Arbor, MI 48108-2738 Tel: +1 734 222-1600 Fax: +1 734 222-1602 E-mail: jhaas@nexthop.com skh@nexthop.com" DESCRIPTION "The MIB module for the BGP-4 protocol. Copyright (C) The Internet Society (2004). This version of this MIB module is part of RFC yyyy; see the RFC itself for full legal notices." -- RFC Ed.: replace yyyy with actual RFC number & remove this note REVISION "200408310000Z" DESCRIPTION "Changes from RFC 1657: 1) Fixed the definitions of the notifications to make them equivalent to their initial definition in RFC 1269. 2) Added compliance and conformance info. 3) Updated information for the values of Expires February 2005 [Page 4] INTERNET DRAFT BGP4-MIB August 2004 bgpPeerNegotiatedVersion, bgp4PathAttrLocalPref, bgp4PathAttrCalcLocalPref, bgp4PathAttrMultiExitDisc, bgp4PathAttrASPathSegement. 4) Added additional clarification comments where needed. 5) Noted where objects do not fully reflect the protocol as Known Issues. 6) Updated the DESCRIPTION for the bgp4PathAttrAtomicAggregate object. 7) The following objects have had their DESCRIPTION clause modified to remove the text that suggested (using 'should' verb) to initialize the counter to zero on a transition to the established state: bgpPeerInUpdates, bgpPeerOutUpdates, bgpPeerInTotalMessages, bgpPeerOutTotalMessages Those implementations that still do this are still compliant with this new wording. Appliciations should not assume counters to have started at zero. Published as RFC yyyy." -- RFC Ed.: replace yyyy with actual RFC number & remove this note REVISION "199405050000Z" DESCRIPTION "Translated to SMIv2 and published as RFC 1657." REVISION "199110261839Z" DESCRIPTION "Initial version, published as RFC 1269." ::= { mib-2 15 } bgpVersion OBJECT-TYPE SYNTAX OCTET STRING (SIZE (1..255)) MAX-ACCESS read-only STATUS current 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 Expires February 2005 [Page 5] INTERNET DRAFT BGP4-MIB August 2004 refers to bit 0). If a bit, i, is present and set, then the version (i+1) of the BGP is supported." REFERENCE "RFC yyyy, Section 4.2." ::= { bgp 1 } -- RFC Ed.: replace yyyy with actual RFC number for the new BGP specification bgpLocalAs OBJECT-TYPE SYNTAX Integer32 (0..65535) MAX-ACCESS read-only STATUS current DESCRIPTION "The local autonomous system number." REFERENCE "RFC yyyy, Section 4.2, 'My Autonomous System'." ::= { bgp 2 } -- RFC Ed.: replace yyyy with actual RFC number for the new BGP specification -- BGP Peer table. This table contains, one entry per -- BGP peer, information about the BGP peer. bgpPeerTable OBJECT-TYPE SYNTAX SEQUENCE OF BgpPeerEntry MAX-ACCESS not-accessible STATUS current DESCRIPTION "BGP peer table. This table contains, one entry per BGP peer, information about the connections with BGP peers." ::= { bgp 3 } bgpPeerEntry OBJECT-TYPE SYNTAX BgpPeerEntry MAX-ACCESS not-accessible STATUS current DESCRIPTION "Entry containing information about the connection with a BGP peer." INDEX { bgpPeerRemoteAddr } ::= { bgpPeerTable 1 } BgpPeerEntry ::= SEQUENCE { Expires February 2005 [Page 6] INTERNET DRAFT BGP4-MIB August 2004 bgpPeerIdentifier IpAddress, bgpPeerState INTEGER, bgpPeerAdminStatus INTEGER, bgpPeerNegotiatedVersion Integer32, bgpPeerLocalAddr IpAddress, bgpPeerLocalPort Integer32, bgpPeerRemoteAddr IpAddress, bgpPeerRemotePort Integer32, bgpPeerRemoteAs Integer32, bgpPeerInUpdates Counter32, bgpPeerOutUpdates Counter32, bgpPeerInTotalMessages Counter32, bgpPeerOutTotalMessages Counter32, bgpPeerLastError OCTET STRING, bgpPeerFsmEstablishedTransitions Counter32, bgpPeerFsmEstablishedTime Gauge32, bgpPeerConnectRetryInterval Integer32, bgpPeerHoldTime Integer32, bgpPeerKeepAlive Integer32, bgpPeerHoldTimeConfigured Integer32, bgpPeerKeepAliveConfigured Integer32, bgpPeerMinASOriginationInterval Integer32, bgpPeerMinRouteAdvertisementInterval Integer32, bgpPeerInUpdateElapsedTime Gauge32 Expires February 2005 [Page 7] INTERNET DRAFT BGP4-MIB August 2004 } bgpPeerIdentifier OBJECT-TYPE SYNTAX IpAddress MAX-ACCESS read-only STATUS current DESCRIPTION "The BGP Identifier of this entry's BGP peer. This entry MUST be 0.0.0.0 unless the bgpPeerState is in the openconfirm or the established state." REFERENCE "RFC yyyy, Section 4.2, 'BGP Identifier'." ::= { bgpPeerEntry 1 } -- RFC Ed.: replace yyyy with actual RFC number for the new BGP specification bgpPeerState OBJECT-TYPE SYNTAX INTEGER { idle(1), connect(2), active(3), opensent(4), openconfirm(5), established(6) } MAX-ACCESS read-only STATUS current DESCRIPTION "The BGP peer connection state." REFERENCE "RFC yyyy, Section 8.2.2." ::= { bgpPeerEntry 2 } -- RFC Ed.: replace yyyy with actual RFC number for the new BGP specification bgpPeerAdminStatus OBJECT-TYPE SYNTAX INTEGER { stop(1), start(2) } MAX-ACCESS read-write STATUS current DESCRIPTION "The desired state of the BGP connection. A transition from 'stop' to 'start' will cause the BGP Manual Start Event to be generated. Expires February 2005 [Page 8] INTERNET DRAFT BGP4-MIB August 2004 A transition from 'start' to 'stop' will cause the BGP Manual 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." REFERENCE "RFC yyyy, Section 8.1.2." ::= { bgpPeerEntry 3 } -- RFC Ed.: replace yyyy with actual RFC number for the new BGP specification bgpPeerNegotiatedVersion OBJECT-TYPE SYNTAX Integer32 MAX-ACCESS read-only STATUS current DESCRIPTION "The negotiated version of BGP running between the two peers. This entry MUST be zero (0) unless the bgpPeerState is in the openconfirm or the established state. Note that legal values for this object are between 0 and 255." REFERENCE "RFC yyyy, Section 4.2. RFC yyyy, Section 7." ::= { bgpPeerEntry 4 } -- RFC Ed.: replace yyyy with actual RFC number for the new BGP specification bgpPeerLocalAddr OBJECT-TYPE SYNTAX IpAddress MAX-ACCESS read-only STATUS current DESCRIPTION "The local IP address of this entry's BGP connection." ::= { bgpPeerEntry 5 } bgpPeerLocalPort OBJECT-TYPE SYNTAX Integer32 (0..65535) MAX-ACCESS read-only STATUS current DESCRIPTION Expires February 2005 [Page 9] INTERNET DRAFT BGP4-MIB August 2004 "The local port for the TCP connection between the BGP peers." ::= { bgpPeerEntry 6 } bgpPeerRemoteAddr OBJECT-TYPE SYNTAX IpAddress MAX-ACCESS read-only STATUS current DESCRIPTION "The remote IP address of this entry's BGP peer." ::= { bgpPeerEntry 7 } bgpPeerRemotePort OBJECT-TYPE SYNTAX Integer32 (0..65535) MAX-ACCESS read-only STATUS current DESCRIPTION "The remote port for the TCP connection between the BGP peers. Note that the objects bgpPeerLocalAddr, bgpPeerLocalPort, bgpPeerRemoteAddr and bgpPeerRemotePort provide the appropriate reference to the standard MIB TCP connection table." ::= { bgpPeerEntry 8 } bgpPeerRemoteAs OBJECT-TYPE SYNTAX Integer32 (0..65535) MAX-ACCESS read-only STATUS current DESCRIPTION "The remote autonomous system number." REFERENCE "RFC yyyy, Section 4.2." ::= { bgpPeerEntry 9 } -- RFC Ed.: replace yyyy with actual RFC number for the new BGP specification bgpPeerInUpdates OBJECT-TYPE SYNTAX Counter32 MAX-ACCESS read-only STATUS current DESCRIPTION "The number of BGP UPDATE messages Expires February 2005 [Page 10] INTERNET DRAFT BGP4-MIB August 2004 received on this connection." REFERENCE "RFC yyyy, Section 4.3." ::= { bgpPeerEntry 10 } -- RFC Ed.: replace yyyy with actual RFC number for the new BGP specification bgpPeerOutUpdates OBJECT-TYPE SYNTAX Counter32 MAX-ACCESS read-only STATUS current DESCRIPTION "The number of BGP UPDATE messages transmitted on this connection." REFERENCE "RFC yyyy, Section 4.3." ::= { bgpPeerEntry 11 } -- RFC Ed.: replace yyyy with actual RFC number for the new BGP specification bgpPeerInTotalMessages OBJECT-TYPE SYNTAX Counter32 MAX-ACCESS read-only STATUS current DESCRIPTION "The total number of messages received from the remote peer on this connection." REFERENCE "RFC yyyy, Section 4." ::= { bgpPeerEntry 12 } -- RFC Ed.: replace yyyy with actual RFC number for the new BGP specification bgpPeerOutTotalMessages OBJECT-TYPE SYNTAX Counter32 MAX-ACCESS read-only STATUS current DESCRIPTION "The total number of messages transmitted to the remote peer on this connection." REFERENCE "RFC yyyy, Section 4." ::= { bgpPeerEntry 13 } -- RFC Ed.: replace yyyy with actual RFC number for the new BGP specification bgpPeerLastError OBJECT-TYPE SYNTAX OCTET STRING (SIZE (2)) Expires February 2005 [Page 11] INTERNET DRAFT BGP4-MIB August 2004 MAX-ACCESS read-only STATUS current 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, and the second byte contains the subcode." REFERENCE "RFC yyyy, Section 4.5." ::= { bgpPeerEntry 14 } -- RFC Ed.: replace yyyy with actual RFC number for the new BGP specification bgpPeerFsmEstablishedTransitions OBJECT-TYPE SYNTAX Counter32 MAX-ACCESS read-only STATUS current DESCRIPTION "The total number of times the BGP FSM transitioned into the established state for this peer." REFERENCE "RFC yyyy, Section 8." ::= { bgpPeerEntry 15 } -- RFC Ed.: replace yyyy with actual RFC number for the new BGP specification bgpPeerFsmEstablishedTime OBJECT-TYPE SYNTAX Gauge32 UNITS "seconds" MAX-ACCESS read-only STATUS current DESCRIPTION "This timer indicates how long (in seconds) this peer has been in the established state or how long since this peer was last in the established state. It is set to zero when a new peer is configured or the router is booted." REFERENCE "RFC yyyy, Section 8." ::= { bgpPeerEntry 16 } -- RFC Ed.: replace yyyy with actual RFC number for the new BGP specification Expires February 2005 [Page 12] INTERNET DRAFT BGP4-MIB August 2004 bgpPeerConnectRetryInterval OBJECT-TYPE SYNTAX Integer32 (1..65535) UNITS "seconds" MAX-ACCESS read-write STATUS current DESCRIPTION "Time interval in seconds for the ConnectRetry timer. The suggested value for this timer is 120 seconds." REFERENCE "RFC yyyy, Section 8.2.2. This is the value used to initialize the 'ConnectRetryTimer'." ::= { bgpPeerEntry 17 } -- RFC Ed.: replace yyyy with actual RFC number for the new BGP specification bgpPeerHoldTime OBJECT-TYPE SYNTAX Integer32 ( 0 | 3..65535 ) UNITS "seconds" MAX-ACCESS read-only STATUS current DESCRIPTION "Time interval in seconds for the Hold Timer established with the peer. The value of this object is calculated by this BGP speaker by using the smaller of the value in bgpPeerHoldTimeConfigured and the Hold Time received in the OPEN message. This value must be at least three seconds if it is not zero (0). If the Hold Timer has not been established with the peer this object MUST have a value of zero (0). If the bgpPeerHoldTimeConfigured object has a value of (0), then this object MUST have a value of (0)." REFERENCE "RFC yyyy, Section 4.2." -- RFC Ed.: replace yyyy with actual RFC number for the new BGP specification ::= { bgpPeerEntry 18 } bgpPeerKeepAlive OBJECT-TYPE SYNTAX Integer32 ( 0 | 1..21845 ) UNITS "seconds" Expires February 2005 [Page 13] INTERNET DRAFT BGP4-MIB August 2004 MAX-ACCESS read-only STATUS current DESCRIPTION "Time interval in seconds for the KeepAlive timer established with the peer. The value of this object is calculated by this BGP speaker such that, when compared with bgpPeerHoldTime, it has the same proportion as what bgpPeerKeepAliveConfigured has when compared with bgpPeerHoldTimeConfigured. If the KeepAlive timer has not been established with the peer this object MUST have a value of zero (0). If the of bgpPeerKeepAliveConfigured object has a value of (0), then this object MUST have a value of (0)." REFERENCE "RFC yyyy, Section 4.4." -- RFC Ed.: replace yyyy with actual RFC number for the new BGP specification ::= { bgpPeerEntry 19 } bgpPeerHoldTimeConfigured OBJECT-TYPE SYNTAX Integer32 ( 0 | 3..65535 ) UNITS "seconds" MAX-ACCESS read-write STATUS current DESCRIPTION "Time interval in seconds for the Hold Time configured for this BGP speaker with this peer. This value is placed in an OPEN message sent to this peer by this BGP speaker, and is compared with the Hold Time field in an OPEN message received from the peer when determining the Hold Time (bgpPeerHoldTime) with the peer. This value must not be less than three seconds if it is not zero (0) in which case the Hold Time is NOT to be established with the peer. The suggested value for this timer is 90 seconds." REFERENCE "RFC yyyy, Section 4.2." -- RFC Ed.: replace yyyy with actual RFC number for the new BGP specification ::= { bgpPeerEntry 20 } Expires February 2005 [Page 14] INTERNET DRAFT BGP4-MIB August 2004 bgpPeerKeepAliveConfigured OBJECT-TYPE SYNTAX Integer32 ( 0 | 1..21845 ) UNITS "seconds" MAX-ACCESS read-write STATUS current DESCRIPTION "Time interval in seconds for the KeepAlive timer configured for this BGP speaker with this peer. The value of this object will only determine the KEEPALIVE messages' frequency relative to the value specified in bgpPeerHoldTimeConfigured; the actual time interval for the KEEPALIVE messages is indicated by bgpPeerKeepAlive. A reasonable maximum value for this timer would be configured to be one third of that of bgpPeerHoldTimeConfigured. If the value of this object is zero (0), no periodical KEEPALIVE messages are sent to the peer after the BGP connection has been established. The suggested value for this timer is 30 seconds." REFERENCE "RFC yyyy, Section 4.4." -- RFC Ed.: replace yyyy with actual RFC number for the new BGP specification ::= { bgpPeerEntry 21 } bgpPeerMinASOriginationInterval OBJECT-TYPE SYNTAX Integer32 (1..65535) UNITS "seconds" MAX-ACCESS read-write STATUS current DESCRIPTION "Time interval in seconds for the MinASOriginationInterval timer. The suggested value for this timer is 15 seconds." REFERENCE "RFC yyyy, Section 9.2.1.2." -- RFC Ed.: replace yyyy with actual RFC number for the new BGP specification ::= { bgpPeerEntry 22 } bgpPeerMinRouteAdvertisementInterval OBJECT-TYPE SYNTAX Integer32 (1..65535) Expires February 2005 [Page 15] INTERNET DRAFT BGP4-MIB August 2004 UNITS "seconds" MAX-ACCESS read-write STATUS current DESCRIPTION "Time interval in seconds for the MinRouteAdvertisementInterval timer. The suggested value for this timer is 30 seconds." REFERENCE "RFC yyyy, Section 9.2.1.1." -- RFC Ed.: replace yyyy with actual RFC number for the new BGP specification ::= { bgpPeerEntry 23 } bgpPeerInUpdateElapsedTime OBJECT-TYPE SYNTAX Gauge32 UNITS "seconds" MAX-ACCESS read-only STATUS current DESCRIPTION "Elapsed time in seconds since the last BGP UPDATE message was received from the peer. Each time bgpPeerInUpdates is incremented, the value of this object is set to zero (0)." REFERENCE "RFC yyyy, Section 4.3. RFC yyyy, Section 8.2.2, Established state." -- RFC Ed.: replace yyyy with actual RFC number for the new BGP specification ::= { bgpPeerEntry 24 } bgpIdentifier OBJECT-TYPE SYNTAX IpAddress MAX-ACCESS read-only STATUS current DESCRIPTION "The BGP Identifier of the local system." REFERENCE "RFC yyyy, Section 4.2." -- RFC Ed.: replace yyyy with actual RFC number for the new BGP specification ::= { bgp 4 } -- BGP Received Path Attribute Table. This table contains, -- one entry per path to a network, path attributes -- received from all peers running BGP version 3 or less. -- This table is obsolete, having been replaced in -- functionality with the bgp4PathAttrTable. Expires February 2005 [Page 16] INTERNET DRAFT BGP4-MIB August 2004 bgpRcvdPathAttrTable OBJECT-TYPE SYNTAX SEQUENCE OF BgpPathAttrEntry MAX-ACCESS not-accessible STATUS obsolete DESCRIPTION "The BGP Received Path Attribute Table contains information about paths to destination networks received from all peers running BGP version 3 or less." ::= { bgp 5 } bgpPathAttrEntry OBJECT-TYPE SYNTAX BgpPathAttrEntry MAX-ACCESS not-accessible STATUS obsolete 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 Integer32 } bgpPathAttrPeer OBJECT-TYPE SYNTAX IpAddress MAX-ACCESS read-only STATUS obsolete DESCRIPTION "The IP address of the peer where the path information was learned." ::= { bgpPathAttrEntry 1 } Expires February 2005 [Page 17] INTERNET DRAFT BGP4-MIB August 2004 bgpPathAttrDestNetwork OBJECT-TYPE SYNTAX IpAddress MAX-ACCESS read-only STATUS obsolete DESCRIPTION "The address of the destination network." REFERENCE "RFC 1267, Section 4.3." ::= { bgpPathAttrEntry 2 } bgpPathAttrOrigin OBJECT-TYPE SYNTAX INTEGER { igp(1),-- networks are interior egp(2),-- networks learned via the -- EGP protocol incomplete(3) -- networks that -- are learned by some other -- means } MAX-ACCESS read-only STATUS obsolete DESCRIPTION "The ultimate origin of the path information." REFERENCE "RFC 1267, Section 4.3. RFC 1267, Section 5." ::= { bgpPathAttrEntry 3 } bgpPathAttrASPath OBJECT-TYPE SYNTAX OCTET STRING (SIZE (2..255)) MAX-ACCESS read-only STATUS obsolete 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;" REFERENCE "RFC 1267, Section 4.3. RFC 1267, Section 5." ::= { bgpPathAttrEntry 4 } Expires February 2005 [Page 18] INTERNET DRAFT BGP4-MIB August 2004 bgpPathAttrNextHop OBJECT-TYPE SYNTAX IpAddress MAX-ACCESS read-only STATUS obsolete DESCRIPTION "The address of the border router that should be used for the destination network." REFERENCE "RFC 1267, Section 4.3. RFC 1267, Section 5." ::= { bgpPathAttrEntry 5 } bgpPathAttrInterASMetric OBJECT-TYPE SYNTAX Integer32 MAX-ACCESS read-only STATUS obsolete DESCRIPTION "The optional inter-AS metric. If this attribute has not been provided for this route, the value for this object is 0." REFERENCE "RFC 1267, Section 4.3. RFC 1267, Section 5." ::= { bgpPathAttrEntry 6 } -- BGP-4 Received Path Attribute Table. This table -- contains, one entry per path to a network, path -- attributes received from all peers running BGP-4. bgp4PathAttrTable OBJECT-TYPE SYNTAX SEQUENCE OF Bgp4PathAttrEntry MAX-ACCESS not-accessible STATUS current DESCRIPTION "The BGP-4 Received Path Attribute Table contains information about paths to destination networks received from all BGP4 peers." ::= { bgp 6 } bgp4PathAttrEntry OBJECT-TYPE SYNTAX Bgp4PathAttrEntry MAX-ACCESS not-accessible Expires February 2005 [Page 19] INTERNET DRAFT BGP4-MIB August 2004 STATUS current DESCRIPTION "Information about a path to a network." INDEX { bgp4PathAttrIpAddrPrefix, bgp4PathAttrIpAddrPrefixLen, bgp4PathAttrPeer } ::= { bgp4PathAttrTable 1 } Bgp4PathAttrEntry ::= SEQUENCE { bgp4PathAttrPeer IpAddress, bgp4PathAttrIpAddrPrefixLen Integer32, bgp4PathAttrIpAddrPrefix IpAddress, bgp4PathAttrOrigin INTEGER, bgp4PathAttrASPathSegment OCTET STRING, bgp4PathAttrNextHop IpAddress, bgp4PathAttrMultiExitDisc Integer32, bgp4PathAttrLocalPref Integer32, bgp4PathAttrAtomicAggregate INTEGER, bgp4PathAttrAggregatorAS Integer32, bgp4PathAttrAggregatorAddr IpAddress, bgp4PathAttrCalcLocalPref Integer32, bgp4PathAttrBest INTEGER, bgp4PathAttrUnknown OCTET STRING } bgp4PathAttrPeer OBJECT-TYPE SYNTAX IpAddress MAX-ACCESS read-only STATUS current DESCRIPTION "The IP address of the peer where the path information was learned." Expires February 2005 [Page 20] INTERNET DRAFT BGP4-MIB August 2004 ::= { bgp4PathAttrEntry 1 } bgp4PathAttrIpAddrPrefixLen OBJECT-TYPE SYNTAX Integer32 (0..32) MAX-ACCESS read-only STATUS current DESCRIPTION "Length in bits of the IP address prefix in the Network Layer Reachability Information field." ::= { bgp4PathAttrEntry 2 } bgp4PathAttrIpAddrPrefix OBJECT-TYPE SYNTAX IpAddress MAX-ACCESS read-only STATUS current DESCRIPTION "An IP address prefix in the Network Layer Reachability Information field. This object is an IP address containing the prefix with length specified by bgp4PathAttrIpAddrPrefixLen. Any bits beyond the length specified by bgp4PathAttrIpAddrPrefixLen are zeroed." REFERENCE "RFC yyyy, Section 4.3." -- RFC Ed.: replace yyyy with actual RFC number for the new BGP specification ::= { bgp4PathAttrEntry 3 } bgp4PathAttrOrigin OBJECT-TYPE SYNTAX INTEGER { igp(1),-- networks are interior egp(2),-- networks learned via the -- EGP protocol incomplete(3) -- networks that -- are learned by some other -- means } MAX-ACCESS read-only STATUS current DESCRIPTION "The ultimate origin of the path information." REFERENCE "RFC yyyy, Section 4.3. Expires February 2005 [Page 21] INTERNET DRAFT BGP4-MIB August 2004 RFC yyyy, Section 5.1.1." -- RFC Ed.: replace yyyy with actual RFC number for the new BGP specification ::= { bgp4PathAttrEntry 4 } bgp4PathAttrASPathSegment OBJECT-TYPE SYNTAX OCTET STRING (SIZE (2..255)) MAX-ACCESS read-only STATUS current DESCRIPTION "The sequence of AS path segments. Each AS path segment is represented by a triple . 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; Known Issues: o BGP Confederations will result in a value of either 3 or 4. o An AS Path may be longer than 255 octets. This may result in this object containing a truncated AS Path." REFERENCE "RFC yyyy, Section 4.3. RFC yyyy, Section 5.1.2." -- RFC Ed.: replace yyyy with actual RFC number for the new BGP specification ::= { bgp4PathAttrEntry 5 } Expires February 2005 [Page 22] INTERNET DRAFT BGP4-MIB August 2004 bgp4PathAttrNextHop OBJECT-TYPE SYNTAX IpAddress MAX-ACCESS read-only STATUS current DESCRIPTION "The address of the border router that should be used for the destination network. This address is the nexthop address received in the UPDATE packet." REFERENCE "RFC yyyy, Section 4.3. RFC yyyy, Section 5.1.3." -- RFC Ed.: replace yyyy with actual RFC number for the new BGP specification ::= { bgp4PathAttrEntry 6 } bgp4PathAttrMultiExitDisc OBJECT-TYPE SYNTAX Integer32 (-1..2147483647) MAX-ACCESS read-only STATUS current DESCRIPTION "This metric is used to discriminate between multiple exit points to an adjacent autonomous system. A value of -1 indicates the absence of this attribute. Known Issues: o The BGP-4 specification uses an unsigned 32 bit number and thus this object cannot represent the full range of the protocol." REFERENCE "RFC yyyy, Section 4.3. RFC yyyy, Section 5.1.4." -- RFC Ed.: replace yyyy with actual RFC number for the new BGP specification ::= { bgp4PathAttrEntry 7 } bgp4PathAttrLocalPref OBJECT-TYPE SYNTAX Integer32 (-1..2147483647) MAX-ACCESS read-only STATUS current DESCRIPTION "The originating BGP4 speaker's degree of preference for an advertised route. A value of -1 indicates the absence of this attribute. Expires February 2005 [Page 23] INTERNET DRAFT BGP4-MIB August 2004 Known Issues: o The BGP-4 specification uses an unsigned 32 bit number and thus this object cannot represent the full range of the protocol." REFERENCE "RFC yyyy, Section 4.3. RFC yyyy, Section 5.1.5." -- RFC Ed.: replace yyyy with actual RFC number for the new BGP specification ::= { bgp4PathAttrEntry 8 } bgp4PathAttrAtomicAggregate OBJECT-TYPE SYNTAX INTEGER { lessSpecificRouteNotSelected(1), -- Typo corrected from RFC 1657 lessSpecificRouteSelected(2) } MAX-ACCESS read-only STATUS current DESCRIPTION "If the ATOMIC_AGGREGATE attribute is present in the Path Attributes then this object MUST have a value of 'lessSpecificRouteNotSelected'. If the ATOMIC_AGGREGATE attribute is missing in the Path Attributes then this object MUST have a value of 'lessSpecificRouteSelected'. Note that ATOMIC_AGGREGATE is now a primarily informational attribute." REFERENCE "RFC yyyy, Sections 5.1.6 and 9.1.4." -- RFC Ed.: Replace yyyy with latest BGP RFC ::= { bgp4PathAttrEntry 9 } bgp4PathAttrAggregatorAS OBJECT-TYPE SYNTAX Integer32 (0..65535) MAX-ACCESS read-only STATUS current DESCRIPTION "The AS number of the last BGP4 speaker that performed route aggregation. A value of zero (0) indicates the absence of this attribute. Note that propagation of AS of zero is illegal Expires February 2005 [Page 24] INTERNET DRAFT BGP4-MIB August 2004 in the Internet." REFERENCE "RFC yyyy, Section 5.1.7. RFC yyyy, Section 9.2.2.2." -- RFC Ed.: replace yyyy with actual RFC number for the new BGP specification ::= { bgp4PathAttrEntry 10 } bgp4PathAttrAggregatorAddr OBJECT-TYPE SYNTAX IpAddress MAX-ACCESS read-only STATUS current DESCRIPTION "The IP address of the last BGP4 speaker that performed route aggregation. A value of 0.0.0.0 indicates the absence of this attribute." REFERENCE "RFC yyyy, Section 5.1.7. RFC yyyy, Section 9.2.2.2." -- RFC Ed.: replace yyyy with actual RFC number for the new BGP specification ::= { bgp4PathAttrEntry 11 } bgp4PathAttrCalcLocalPref OBJECT-TYPE SYNTAX Integer32 (-1..2147483647) MAX-ACCESS read-only STATUS current DESCRIPTION "The degree of preference calculated by the receiving BGP4 speaker for an advertised route. A value of -1 indicates the absence of this attribute. Known Issues: o The BGP-4 specification uses an unsigned 32 bit number and thus this object cannot represent the full range of the protocol." REFERENCE "RFC yyyy, Section 9.1.1." -- RFC Ed.: replace yyyy with actual RFC number for the new BGP specification ::= { bgp4PathAttrEntry 12 } bgp4PathAttrBest OBJECT-TYPE SYNTAX INTEGER { false(1),-- not chosen as best route Expires February 2005 [Page 25] INTERNET DRAFT BGP4-MIB August 2004 true(2) -- chosen as best route } MAX-ACCESS read-only STATUS current DESCRIPTION "An indication of whether or not this route was chosen as the best BGP4 route for this destination." REFERENCE "RFC yyyy, Section 9.1.2." -- RFC Ed.: replace yyyy with actual RFC number for the new BGP specification ::= { bgp4PathAttrEntry 13 } bgp4PathAttrUnknown OBJECT-TYPE SYNTAX OCTET STRING (SIZE(0..255)) MAX-ACCESS read-only STATUS current DESCRIPTION "One or more path attributes not understood by this BGP4 speaker. Path attributes are recorded in the Update Path attribute format of type, length, value. Size zero (0) indicates the absence of such attributes. Octets beyond the maximum size, if any, are not recorded by this object. Known Issues: o Attributes understood by this speaker, but not represented in this MIB, are unavailable to the agent." ::= { bgp4PathAttrEntry 14 } -- Traps. -- Note that in RFC 1657, bgpTraps was incorrectly -- assigned a value of { bgp 7 } and each of the -- traps had the bgpPeerRemoteAddr object inappropriately -- removed from their OBJECTS clause. The following -- definitions restore the semantics of the traps as -- they were initially defined in RFC 1269. Expires February 2005 [Page 26] INTERNET DRAFT BGP4-MIB August 2004 bgpNotification OBJECT IDENTIFIER ::= { bgp 0 } bgpEstablishedNotification NOTIFICATION-TYPE OBJECTS { bgpPeerRemoteAddr, bgpPeerLastError, bgpPeerState } STATUS current DESCRIPTION "The BGP Established event is generated when the BGP FSM enters the ESTABLISHED state. This Notification replaces the bgpEstablished Notification." ::= { bgpNotification 1 } bgpBackwardTransNotification NOTIFICATION-TYPE OBJECTS { bgpPeerRemoteAddr, bgpPeerLastError, bgpPeerState } STATUS current DESCRIPTION "The BGPBackwardTransNotification Event is generated when the BGP FSM moves from a higher numbered state to a lower numbered state. This Notification replaces the bgpBackwardsTransition Notification." ::= { bgpNotification 2 } -- { bgp 7 } is deprecated. Do not allocate new objects or -- notifications underneath this branch. bgpTraps OBJECT IDENTIFIER ::= { bgp 7 } -- deprecated bgpEstablished NOTIFICATION-TYPE OBJECTS { bgpPeerLastError, bgpPeerState } STATUS deprecated DESCRIPTION "The BGP Established event is generated when the BGP FSM enters the ESTABLISHED state. This Notification has been replaced by the Expires February 2005 [Page 27] INTERNET DRAFT BGP4-MIB August 2004 bgpEstablishedNotification Notification." ::= { bgpTraps 1 } bgpBackwardTransition NOTIFICATION-TYPE OBJECTS { bgpPeerLastError, bgpPeerState } STATUS deprecated DESCRIPTION "The BGPBackwardTransition Event is generated when the BGP FSM moves from a higher numbered state to a lower numbered state. This Notification has been replaced by the bgpBackwardTransNotification Notification." ::= { bgpTraps 2 } -- Conformance information bgp4MIBConformance OBJECT IDENTIFIER ::= { bgp 8 } bgp4MIBCompliances OBJECT IDENTIFIER ::= { bgp4MIBConformance 1 } bgp4MIBGroups OBJECT IDENTIFIER ::= { bgp4MIBConformance 2 } -- Compliance statements bgp4MIBCompliance MODULE-COMPLIANCE STATUS current DESCRIPTION "The compliance statement for entities which implement the BGP4 mib." MODULE -- this module MANDATORY-GROUPS { bgp4MIBGlobalsGroup, bgp4MIBPeerGroup, bgp4MIBPathAttrGroup } GROUP bgp4MIBNotificationGroup DESCRIPTION "Implementation of BGP Notifications are completely optional in this MIB." ::= { bgp4MIBCompliances 1 } Expires February 2005 [Page 28] INTERNET DRAFT BGP4-MIB August 2004 bgp4MIBDeprecatedCompliances MODULE-COMPLIANCE STATUS deprecated DESCRIPTION "The compliance statement documenting deprecated objects in the BGP4 mib." MODULE -- this module GROUP bgp4MIBTrapGroup DESCRIPTION "Group containing TRAP objects that were improperly converted from SMIv1 in RFC 1657. The proper semantics have been restored with the objects in bgp4MIBNotificationGroup." ::= { bgp4MIBCompliances 2 } bgp4MIBObsoleteCompliances MODULE-COMPLIANCE STATUS obsolete DESCRIPTION "The compliance statement documenting obsolete objects in the BGP4 mib." MODULE -- this module GROUP bgpRcvdPathAttrGroup DESCRIPTION "Group containing objects relevant to BGP-3 and earlier objects." ::= { bgp4MIBCompliances 3 } -- Units of conformance bgp4MIBGlobalsGroup OBJECT-GROUP OBJECTS { bgpVersion, bgpLocalAs, bgpIdentifier } STATUS current DESCRIPTION "A collection of objects providing information on global BGP state." ::= { bgp4MIBGroups 1 } bgp4MIBPeerGroup OBJECT-GROUP OBJECTS { bgpPeerIdentifier, bgpPeerState, bgpPeerAdminStatus, bgpPeerNegotiatedVersion, bgpPeerLocalAddr, bgpPeerLocalPort, Expires February 2005 [Page 29] INTERNET DRAFT BGP4-MIB August 2004 bgpPeerRemoteAddr, bgpPeerRemotePort, bgpPeerRemoteAs, bgpPeerInUpdates, bgpPeerOutUpdates, bgpPeerInTotalMessages, bgpPeerOutTotalMessages, bgpPeerLastError, bgpPeerFsmEstablishedTransitions, bgpPeerFsmEstablishedTime, bgpPeerConnectRetryInterval, bgpPeerHoldTime, bgpPeerKeepAlive, bgpPeerHoldTimeConfigured, bgpPeerKeepAliveConfigured, bgpPeerMinASOriginationInterval, bgpPeerMinRouteAdvertisementInterval, bgpPeerInUpdateElapsedTime } STATUS current DESCRIPTION "A collection of objects for managing BGP peers." ::= { bgp4MIBGroups 2 } bgpRcvdPathAttrGroup OBJECT-GROUP OBJECTS { bgpPathAttrPeer, bgpPathAttrDestNetwork, bgpPathAttrOrigin, bgpPathAttrASPath, bgpPathAttrNextHop, bgpPathAttrInterASMetric } STATUS obsolete DESCRIPTION "A collection of objects for managing BGP-3 and earlier path entries. This conformance group, like BGP-3, is obsolete." ::= { bgp4MIBGroups 3 } bgp4MIBPathAttrGroup OBJECT-GROUP OBJECTS { bgp4PathAttrPeer, bgp4PathAttrIpAddrPrefixLen, bgp4PathAttrIpAddrPrefix, bgp4PathAttrOrigin, bgp4PathAttrASPathSegment, bgp4PathAttrNextHop, Expires February 2005 [Page 30] INTERNET DRAFT BGP4-MIB August 2004 bgp4PathAttrMultiExitDisc, bgp4PathAttrLocalPref, bgp4PathAttrAtomicAggregate, bgp4PathAttrAggregatorAS, bgp4PathAttrAggregatorAddr, bgp4PathAttrCalcLocalPref, bgp4PathAttrBest, bgp4PathAttrUnknown } STATUS current DESCRIPTION "A collection of objects for managing BGP path entries." ::= { bgp4MIBGroups 4 } bgp4MIBTrapGroup NOTIFICATION-GROUP NOTIFICATIONS { bgpEstablished, bgpBackwardTransition } STATUS deprecated DESCRIPTION "A collection of notifications for signaling changes in BGP peer relationships. Obsoleted by bgp4MIBNotificationGroup" ::= { bgp4MIBGroups 5 } bgp4MIBNotificationGroup NOTIFICATION-GROUP NOTIFICATIONS { bgpEstablishedNotification, bgpBackwardTransNotification } STATUS current DESCRIPTION "A collection of notifications for signaling changes in BGP peer relationships. Obsoletes bgp4MIBTrapGroup." ::= { bgp4MIBGroups 6 } END Expires February 2005 [Page 31] INTERNET DRAFT BGP4-MIB August 2004 5. Intellectual Property The IETF takes no position regarding the validity or scope of any intellectual property 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; neither does it represent that it has made any effort to identify any such rights. Information on the IETF's procedures with respect to rights in standards-track and standards-related documentation can be found in BCP-11. Copies of claims of rights made available for publication 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 implementors or users of this specification can be obtained from the IETF Secretariat. The IETF invites any interested party to bring to its attention any copyrights, patents or patent applications, or other proprietary rights which may cover technology that may be required to practice this standard. Please address the information to the IETF Executive Director. Expires February 2005 [Page 32] INTERNET DRAFT BGP4-MIB August 2004 6. Security Considerations This MIB relates to a system providing inter-domain routing. As such, improper manipulation of the objects represented by this MIB may result in denial of service to a large number of end-users. There are several management objects defined in this MIB that have a MAX-ACCESS clause of read-write and/or read-create. Such objects should be considered sensitive or vulnerable in most network environments. The support for SET operations in a non-secure environment without proper protection can have a negative effect on network operations. These objects include: o bgpPeerAdminStatus Improper change of bgpPeerAdminStatus from start to stop can cause significant disruption of the connectivity to those portions of the Internet reached via the applicable remote BGP peer. o bgpPeerConnectRetryInterval Improper change of this object can cause connections to be disrupted for extremely long time periods when otherwise they would be restored in a relatively short period of time. o bgpPeerHoldTimeConfigured, bgpPeerKeepAliveConfigured Misconfiguration of these objects can make BGP sessions more fragile and less resilient to denial of service attacks on the inter-domain routing system. o bgpPeerMinASOriginationInterval, bgpPeerMinRouteAdvertisementInterval Misconfiguration of these objects may adversely affect global Internet convergence of the routes advertised by this BGP speaker. This may result in long-lived routing loops and blackholes for the portions of the Internet that utilize these routes." There are a number of managed objects in this MIB that contain sensitive information regarding the operation of a network. For example, a BGP peer's local and remote addresses might be sensitive for ISPs who want to keep interface addresses on routers confidential to prevent router addresses used for a denial of service attack or spoofing. Expires February 2005 [Page 33] INTERNET DRAFT BGP4-MIB August 2004 Therefore, it is important in most environments to control read access to these objects and possibly to even encrypt the values of these object when sending them over the network via SNMP. SNMPv1 by itself is not a secure environment. Even if the network itself is secure (for example by using IPSec), there is still no control as to who on the secure network is allowed to access and GET/SET (read/change/create/delete) the objects in this MIB. It is recommended that the implementers consider the security features as provided by the SNMPv3 framework.[REF] Specifically, the implementation and use of the User-based Security Model [REF] and the View-based Access Control Model [REF] is recommended to provide appropriate security controls. It is then an operator/user responsibility to ensure that the SNMP entity giving access to an instance of this MIB, is properly configured to give access to the objects only to those principals (users) that have legitimate rights to indeed GET or SET (change/create/delete) them. Expires February 2005 [Page 34] INTERNET DRAFT BGP4-MIB August 2004 7. Acknowledgements We would like to acknowledge the assistance of all the members of the Inter-Domain Routing Working Group, and particularly the following individuals: Yakov Rekhter, Juniper Networks Rob Coltun, Redback Guy Almes, Internet2 Jeff Honig, BSDi Marshall T. Rose, Dover Beach Consulting, Inc. Dennis Ferguson, Juniper Networks Matt Mathis, PSC John Krawczyk, Bay Networks Curtis Villamizar, Avici Dave LeRoy, Pencom Systems Paul Traina, Juniper Networks Andrew Partan, MFN Robert Snyder, Cisco Systems Dimitry Haskin, Nortel Peder Chr Norgaard, Telebit Communications A/S Joel Halpern, CTO Longitude Systems, Inc. Nick Thille, RedBack Networks Bert Wijnen, Lucent Shane Wright, NextHop Technologies Mike McFadden, Riverstone Networks, Inc. Jon Saperia, JDS Consulting, Inc. Wayne Tackabury, Gold Wire Technology, Inc. Bill Fenner, AT&T Research RJ Atkinson, Extreme Networks Dan Romascanu, Avaya The origin of this document is from RFC 1269 "Definitions of Managed Objects for the Border Gateway Protocol (Version 3)" written by Steve Willis and John Burruss, which was updated by John Chu to support BGP-4 in RFC 1657. The editors wish to acknowledge the fine work of these original authors. Expires February 2005 [Page 35] INTERNET DRAFT BGP4-MIB August 2004 8. IANA Considerations This document presents no new IANA considerations. 9. Normative References [BGP4] Rekhter, Y., Li, T., Hares, S., "A Border Gateway Protocol 4 (BGP-4)", RFC yyyy, zzzz 2004. -- RFC Ed.: Replace yyyy with latest BGP RFC and zzzz with its -- month of publication [BGP4APP] Rekhter, Y., Gross, P., "Application of the Border Gateway Protocol in the Internet", RFC 1772, March 1995. [RFC2578] McCloghrie, K., Perkins, D., Schoenwaelder, J., Case, J., Rose, M., and S. Waldbusser, "Structure of Management Information Version 2 (SMIv2)", STD 58, RFC 2578, April 1999. [RFC2579] McCloghrie, K., Perkins, D., Schoenwaelder, J., Case, J., Rose, M., and S. Waldbusser, "Textual Conventions for SMIv2", STD 58, RFC 2579, April 1999. [RFC2580] McCloghrie, K., Perkins, D., Schoenwaelder, J., Case, J., Rose, M., and S. Waldbusser, "Conformance Statements for SMIv2", STD 58, RFC 2580, April 1999. 10. Editors' Address Jeffrey Haas, Susan Hares NextHop Technologies 825 Victor's Way, Suite 100 Ann Arbor, MI 48103 Phone: +1 734 222-1600 Fax: +1 734 222-1602 Email: jhaas@nexthop.com skh@nexthop.com Expires February 2005 [Page 36] INTERNET DRAFT BGP4-MIB August 2004 11. Full Copyright Statement Copyright (C) The Internet Society (2004). All Rights Reserved. This document and translations of it may be copied and furnished to others, and derivative works that comment on or otherwise explain it or assist in its implementation may be prepared, copied, published and distributed, in whole or in part, without restriction of any kind, provided that the above copyright notice and this paragraph are included on all such copies and derivative works. However, this document itself may not be modified in any way, such as by removing the copyright notice or references to the Internet Society or other Internet organizations, except as needed for the purpose of developing Internet standards in which case the procedures for copyrights defined in the Internet Standards process must be followed, or as required to translate it into languages other than English. The limited permissions granted above are perpetual and will not be revoked by the Internet Society or its successors or assigns. This document and the information contained herein is provided on an "AS IS" basis and THE INTERNET SOCIETY AND THE INTERNET ENGINEERING TASK FORCE DISCLAIMS 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. Expires February 2005 [Page 37]