Signaling Entropy Label Capability and Entropy Readable Label Depth Using OSPF
RFC 9089, “Signaling Entropy Label Capability and Entropy Readable Label Depth Using OSPF”, 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 OSPFv2 and OSPFv3, and Border Gateway Protocol - Link State (BGP-LS).
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.
The canonical text of RFC 9089 is hosted at rfc-editor.org. Available in HTML,TXT,PDF,XML.
- RFC 9088 Signaling Entropy Label Capability and Entropy Readable Label Depth Using IS-IS
- RFC 9090 Concise Binary Object Representation Tags for Object Identifiers
- RFC 9087 Segment Routing Centralized BGP Egress Peer Engineering
- RFC 9091 Experimental Domain-Based Message Authentication, Reporting, and Conformance Extension for Public Suffix Domains
- RFC 9086 Border Gateway Protocol - Link State Extensions for Segment Routing BGP Egress Peer Engineering
- RFC 9092 Finding and Using Geofeed Data
- RFC 9085 Border Gateway Protocol - Link State Extensions for Segment Routing
- RFC 9093 A YANG Data Model for Layer 0 Types