RFC 8669 · PROPOSED STANDARD · 2019

Segment Routing Prefix Segment Identifier Extensions for BGP

Overview

RFC 8669, “Segment Routing Prefix Segment Identifier Extensions for BGP”, is a Proposed Standard document published in December 2019 by S. Previdi, C. Filsfils, A. Lindem, A. Sreekantiah, H. Gredler. The canonical text is published by the RFC Editor.

Abstract

Segment Routing (SR) leverages the source-routing paradigm. A node steers a packet through an ordered list of instructions called "segments". A segment can represent any instruction, topological or service based. The ingress node prepends an SR header to a packet containing a set of segment identifiers (SIDs). Each SID represents a topological or service-based instruction. Per-flow state is maintained only on the ingress node of the SR domain. An "SR domain" is defined as a single administrative domain for global SID assignment.

This document defines an optional, transitive BGP attribute for announcing information about BGP Prefix Segment Identifiers (BGP Prefix-SIDs) and the specification for SR-MPLS SIDs.

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 8669 is hosted at rfc-editor.org. Available in HTML,TXT,PDF,XML.

Other RFCs from 2019

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