Segment routing

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Segment routing, a form of computer networking, is a modern variant of source routing that is being developed within the SPRING and IPv6 working groups of the IETF. In a segment routed network, an ingress node may prepend a header to packets that contain a list of segments, which are instructions that are executed on subsequent nodes in the network. These instructions may be forwarding instructions, such as an instruction to forward a packet to a specific destination or interface.

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Segment routing works either on top of a MPLS network or on an IPv6 network. [1] [2] In an MPLS network, segments are encoded as MPLS labels. Under IPv6, a new header called a Segment Routing Header (SRH) is used. Segments in a SRH are encoded in a list of IPv6 addresses. The 5f00::/16 prefix has been allocated for this purpose as part of an Internet-Draft [3] .

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References

  1. "RFC 8402, Segment Routing Architecture". 2017-08-20. Retrieved 2018-06-15.
  2. Filsfils, Clarence; Dukes, Darren; Previdi, Stefano; Leddy, John; Matsushima, Satoru; Voyer, Daniel (2020-03-01). "IPv6 Segment Routing Header (SRH)" . Retrieved 2020-03-01.
  3. Krishnan, S. (2024-02-15). SRv6 Segment Identifiers in the IPv6 Addressing Architecture. IETF. I-D draft-ietf-6man-sids-06. Retrieved 2024-06-13.