RFC 9125 · PROPOSED STANDARD · 2021

Gateway Auto-Discovery and Route Advertisement for Site Interconnection Using Segment Routing

Overview

RFC 9125, “Gateway Auto-Discovery and Route Advertisement for Site Interconnection Using Segment Routing”, is a Proposed Standard document published in August 2021 by A. Farrel, J. Drake, E. Rosen, K. Patel, L. Jalil. The canonical text is published by the RFC Editor.

Abstract

Data centers are attached to the Internet or a backbone network by gateway routers. One data center typically has more than one gateway for commercial, load-balancing, and resiliency reasons. Other sites, such as access networks, also need to be connected across backbone networks through gateways.

This document defines a mechanism using the BGP Tunnel Encapsulation attribute to allow data center gateway routers to advertise routes to the prefixes reachable in the site, including advertising them on behalf of other gateways at the same site. This allows segment routing to be used to identify multiple paths across the Internet or backbone network between different gateways. The paths can be selected for load-balancing, resilience, and quality purposes.

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 9125 is hosted at rfc-editor.org. Available in HTML,TXT,PDF,XML.

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