RFC 8518 · PROPOSED STANDARD · 2019

Selection of Loop-Free Alternates for Multi-Homed Prefixes

Overview

RFC 8518, “Selection of Loop-Free Alternates for Multi-Homed Prefixes”, is a Proposed Standard document published in March 2019 by P. Sarkar, U. Chunduri, S. Hegde, J. Tantsura, H. Gredler. It updates RFC 5286. The canonical text is published by the RFC Editor.

Abstract

Deployment experience gained from implementing algorithms to determine Loop-Free Alternates (LFAs) for multi-homed prefixes (MHPs) has revealed some avenues for potential improvement. This document provides explicit inequalities that can be used to evaluate neighbors as potential alternates for MHPs. It also provides detailed criteria for evaluating potential alternates for external prefixes advertised by OSPF ASBRs. This document updates Section 6 of RFC 5286 by expanding some of the routing aspects.

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 8518 is hosted at rfc-editor.org. Available in TXT,HTML.

Relationships to other RFCs
This RFC updates
RFC 5286
Other RFCs from 2019

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