RFC 9072 · PROPOSED STANDARD · 2021

Extended Optional Parameters Length for BGP OPEN Message

Overview

RFC 9072, “Extended Optional Parameters Length for BGP OPEN Message”, is a Proposed Standard document published in July 2021 by E. Chen, J. Scudder. It updates RFC 4271. The canonical text is published by the RFC Editor.

Abstract

The Optional Parameters in the BGP OPEN message as defined in the base BGP specification are limited to 255 octets due to a one-octet length field. BGP capabilities are carried in this field and may foreseeably exceed 255 octets in the future, leading to concerns about this limitation.

This document updates RFC 4271 by extending, in a backward-compatible manner, the length of the Optional Parameters in a BGP OPEN message. The Parameter Length field of individual Optional Parameters is also extended.

Abstract as published in the RFC, via rfc-editor.org.

What “Proposed Standard” means

An entry-level standards-track specification: stable, peer-reviewed and a solid basis for implementation, though it may still evolve before becoming an Internet Standard.

Read this RFC

The canonical text of RFC 9072 is hosted at rfc-editor.org. Available in HTML,TXT,PDF,XML.

Relationships to other RFCs
This RFC updates
RFC 4271
Other RFCs from 2021

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