Network Working Group K. Patel Internet-Draft Cisco Systems Intended status: Standards Track D. Ward Expires: September 8, 2011 Juniper Networks R. Bush IIJ March 7, 2011 Extended Message support for BGP draft-ymbk-bgp-extended-messages-00 Abstract The current BGP specification mandates a maximum BGP message size of 4096 octets. As BGP is extended to support newer AFI/SAFIs, there is a need to extend the maximum message size beyond 4096 octets. This draft provides an extension for BGP to extend its current message size for BGP messages from 4096 octets to 65535 octets. Requirements Language 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 RFC 2119 [RFC2119]. Status of this Memo This Internet-Draft is submitted in full conformance with the provisions of BCP 78 and BCP 79. Internet-Drafts are working documents of the Internet Engineering Task Force (IETF). Note that other groups may also distribute working documents as Internet-Drafts. The list of current Internet- Drafts is at http://datatracker.ietf.org/drafts/current/. 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." This Internet-Draft will expire on September 8, 2011. Copyright Notice Copyright (c) 2011 IETF Trust and the persons identified as the document authors. All rights reserved. Patel, et al. Expires September 8, 2011 [Page 1] Internet-Draft Extended Message support for BGP March 2011 This document is subject to BCP 78 and the IETF Trust's Legal Provisions Relating to IETF Documents (http://trustee.ietf.org/license-info) in effect on the date of publication of this document. Please review these documents carefully, as they describe your rights and restrictions with respect to this document. Code Components extracted from this document must include Simplified BSD License text as described in Section 4.e of the Trust Legal Provisions and are provided without warranty as described in the Simplified BSD License. Table of Contents 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3 2. Extended message Capability for BGP . . . . . . . . . . . . . . 3 3. Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 4. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 3 5. IANA Considerations . . . . . . . . . . . . . . . . . . . . . . 4 6. Security Considerations . . . . . . . . . . . . . . . . . . . . 4 7. Normative References . . . . . . . . . . . . . . . . . . . . . 4 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 4 Patel, et al. Expires September 8, 2011 [Page 2] Internet-Draft Extended Message support for BGP March 2011 1. Introduction The current BGP specification [RFC4271] mandates a maximum BGP message size of 4096 octets. As BGP is extended to support newer AFI/SAFIs and newer capabilities, there is a need to extend the maximum message size beyond 4096 octets. This draft provides an extension for BGP to extend its current message size for BGP messages from 4096 octets to 65535 octets. 2. Extended message Capability for BGP To advertise BGP Extended Message Capability to a peer, a BGP speaker uses BGP Capabilities Advertisement [RFC3392]. By advertising the BGP Extended message Capability to a peer, a BGP speaker conveys to that peer that the speaker is capable of receiving and properly handling BGP Extended Messages. This is an asymmetric capability. I.e. one speaker could signal the capability and the other not, so that extended messages could flow only in the direction toward the speaker which advertised the capability. The BGP Extended Message Capability is a new BGP Capability [RFC3392] defined with Capability code TBD and Capability length 0. 3. Operation A BGP speaker that is willing to receive BGP Extended Messages from its peer should advertise the BGP Extended Message Capability to its peer using BGP Capabilities Advertisement [RFC3392]. A BGP speaker may send extended messages to its peer only if it has received the Extended Message Capability from its peer. All BGP extended messages have maximum message size of 65535 octets. The smallest message that may be sent consists of a BGP header without a data portion (19 octets). All multi-octet fields are in network byte order. 4. Acknowledgements The authors thank John Scudder for his input. Patel, et al. Expires September 8, 2011 [Page 3] Internet-Draft Extended Message support for BGP March 2011 5. IANA Considerations This document defines the Extended Message Capability for BGP. The new Capability code needs to be assigned by IANA. 6. Security Considerations This extension to BGP does not change BGP's underlying security issues. 7. Normative References [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, March 1997. [RFC3392] Chandra, R. and J. Scudder, "Capabilities Advertisement with BGP-4", RFC 3392, November 2002. [RFC4271] Rekhter, Y., Li, T., and S. Hares, "A Border Gateway Protocol 4 (BGP-4)", RFC 4271, January 2006. Authors' Addresses Keyur Patel Cisco Systems 170 W. Tasman Drive San Jose, CA 95134 USA Email: keyupate@cisco.com Dave Ward Juniper Networks 1194 N. Mathilda Ave Sunnyvale, CA 94089 USA Email: dward@juniper.net Patel, et al. Expires September 8, 2011 [Page 4] Internet-Draft Extended Message support for BGP March 2011 Randy Bush Internet Initiative Japan, Inc. 5147 Crystal Springs Bainbridge Island, Washington 98110 US Phone: +1 206 780 0431 x1 Email: randy@psg.com Patel, et al. Expires September 8, 2011 [Page 5]