RFC 9088 · PROPOSED STANDARD · 2021

Signaling Entropy Label Capability and Entropy Readable Label Depth Using IS-IS

Overview

RFC 9088, “Signaling Entropy Label Capability and Entropy Readable Label Depth Using IS-IS”, is a Proposed Standard document published in August 2021 by X. Xu, S. Kini, P. Psenak, C. Filsfils, S. Litkowski, M. Bocci. The canonical text is published by the RFC Editor.

Abstract

Multiprotocol Label Switching (MPLS) has defined a mechanism to load-balance traffic flows using Entropy Labels (EL). An ingress Label Switching Router (LSR) cannot insert ELs for packets going into a given Label Switched Path (LSP) unless an egress LSR has indicated via signaling that it has the capability to process ELs, referred to as the Entropy Label Capability (ELC), on that LSP. In addition, it would be useful for ingress LSRs to know each LSR's capability for reading the maximum label stack depth and performing EL-based load-balancing, referred to as Entropy Readable Label Depth (ERLD). This document defines a mechanism to signal these two capabilities using IS-IS and Border Gateway Protocol - Link State (BGP-LS).

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 9088 is hosted at rfc-editor.org. Available in HTML,TXT,PDF,XML.

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