RFC 9491: Integration of the Network Service Header (NSH) and Segment Routing for Service Function Chaining (SFC)
In plain English — editorial summary, not part of the RFC
This document describes the integration of the Network Service Header (NSH) and Segment Routing (SR), as well as encapsulation details, to efficiently support Service Function Chaining (SFC) while maintaining separation of the service and transport planes as originally intended by the SFC architecture. Combining these technologies allows SR to be used for steering packets between Service Function Forwarders (SFFs) along a given Service Function Path (SFP), whereas the NSH is responsible for maintaining the integrity of the service plane, the SFC instance context, and any associated metadata. This integration demonstrates that the NSH and SR can work cooperatively and provide a network operator with the flexibility to use whichever transport technology makes sense in specific areas of their network infrastructure while still maintaining an end-to-end service plane using the NSH.
Document record
- Document ID
- RFC9491
- Published
- November 2023
- Authors
- J. Guichard; J. Tantsura
- Status
- PROPOSED STANDARD
- Stream
- IETF
- Area
- rtg
- Pages
- 17
- Also known as
- —
Topics
Related documents
Ranked automatically by shared keywords, IETF area and stream — not by editorial selection.
- RFC 9857Advertisement of Segment Routing Policies Using BGP - Link StateCurrent
October 2025
- RFC 8595An MPLS-Based Forwarding Plane for Service Function ChainingCurrent
June 2019
- RFC 8300Network Service Header (NSH)Updated
January 2018
- RFC 9487Export of Segment Routing over IPv6 Information in IP Flow Information Export (IPFIX)Current
November 2023
- RFC 9513OSPFv3 Extensions for Segment Routing over IPv6 (SRv6)Current
December 2023
- RFC 9514Border Gateway Protocol - Link State (BGP-LS) Extensions for Segment Routing over IPv6 (SRv6)Current
December 2023
- RFC 9603Path Computation Element Communication Protocol (PCEP) Extensions for IPv6 Segment RoutingUpdated
July 2024
- RFC 9256Segment Routing Policy ArchitectureCurrent
July 2022
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The document record above — title, authors, date, status, stream, area, relationships, DOI and errata — is imported verbatim from the public RFC Editor index. The “in plain English” section is editorial: written by The metasystema editorial team, not part of the RFC. Where the two differ, the RFC text governs.
Last checked against the RFC Editor index on . RFCs are never revised after publication; changes are issued as new documents.
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