Integration of the Network Service Header and Segment Routing for Service Function Chaining
RFC 9491, “Integration of the Network Service Header and Segment Routing for Service Function Chaining”, is a Proposed Standard document published in November 2023 by J. Guichard, J. Tantsura. The canonical text is published by the RFC Editor.
Abstract
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.
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 9491 is hosted at rfc-editor.org. Available in HTML,TXT,PDF,XML.
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