IDR J. Heitz
Internet-Draft Cisco
Intended status: Standards Track K. Patel
Expires: March 6, 2017 Arrcus
J. Snijders
I. Bagdonas
A. Simpson
September 2, 2016

Large BGP Community


A new type of BGP community attribute that contains communities that each hold a 4-octet AS number and a 8-octet opaque field is defined.

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 [RFC2119].

Status of This Memo

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This Internet-Draft will expire on March 6, 2017.

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Table of Contents

1. Introduction

A BGP Community attribute is defined that encodes 12 byte communities, suitable for 4-Octet Autonomous System Numbers that require 8 octets of locally significant opaque data.

To ensure rapid and smooth adoption of the new community attribute, it must be as similar to the [RFC1997] community as possible, only bigger.

2. Large BGP Community Attribute

The Large Community Attribute is a transitive optional BGP attribute, with the Type Code (suggested 41) to be assigned by IANA. The attribute consists of a set of "Large Communities". All routes with the Large Community attribute belong to the communities listed in the attribute.

 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
|                      Autonomous System number                 |
|                          Local Data Part 1                    |
|                          Local Data Part 2                    |

Each Large Community is encoded as a 12-octet quantity, as follows:

3. Textual Representation

The textual representation of the Large BGP Community is A:B:C, where A is the Autonomous System number, B is the Local Data part 1 and C is the Local Data part 2. A ranges from 0 to 4294967295. B ranges from 0 to 4294967295. C ranges from 0 to 4294967295. A, B and C are plain decimal non-negative integers without leading zeroes. Each number must appear, even if it is 0. For example, "0:1:2" cannot be written as ":1:2". The string is expected to match the following regular expression: ^[0-9]+:[0-9]+:[0-9]+$

4. Security Considerations


5. IANA Considerations

IANA is requested to assign a BGP path attribute value for the Large community attribute.

6. Acknowledgements

Thanks to Russ White, Acee Lindem, Shyam Sethuram and Jared Mauch for insightful review and comments.

7. Normative References

[RFC1997] Chandra, R., Traina, P. and T. Li, "BGP Communities Attribute", RFC 1997, DOI 10.17487/RFC1997, August 1996.
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, DOI 10.17487/RFC2119, March 1997.

Authors' Addresses

Jakob Heitz Cisco 170 West Tasman Drive San Jose, CA 95054 USA EMail:
Keyur Patel Arrcus, Inc EMail:
Job Snijders NTT Communications, Inc. Theodorus Majofskistraat 100 Amsterdam, 1065 SZ NL EMail:
Ignas Bagdonas Equinix London, UK EMail:
Adam Simpson Nokia 600 March Road Ottawa, Ontario K2K 2E6 Canada EMail: