{ "draft": "draft-ietf-pce-sid-algo-29", "doc_id": "RFC9933", "title": "Carrying SR-Algorithm in Path Computation Element Communication Protocol (PCEP)", "authors": [ "S. Sidor", "Z. Rose", "S. Peng", "S. Peng", "A. Stone" ], "format": [ "XML", "TEXT", "HTML", "PDF" ], "page_count": "26", "pub_status": "PROPOSED STANDARD", "status": "PROPOSED STANDARD", "source": "Path Computation Element", "abstract": "This document specifies extensions to the Path Computation Element Communication Protocol (PCEP) to enhance support for Segment Routing (SR) with a focus on the use of Segment Identifiers (SIDs) and SR-Algorithms in Traffic Engineering (TE). The SR-Algorithm associated with a SID defines the path computation algorithm used by Interior Gateway Protocols (IGPs). It introduces mechanisms for PCEP peers to signal the SR-Algorithm associated with SIDs by encoding this information in Explicit Route Object (ERO) and Record Route Object (RRO) subobjects, enables SR-Algorithm constraints for path computation, and defines new metric types for the METRIC object. This document updates RFC 8664 and RFC 9603 to allow such extensions.", "pub_date": "July 2026", "keywords": [ "Prefix-SID Algorithm", "Flexible Algorithm", "IGP Algorithm Types" ], "obsoletes": [], "obsoleted_by": [], "updates": [ "RFC8664", "RFC9603" ], "updated_by": [], "see_also": [], "doi": "10.17487/RFC9933", "errata_url": null }