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5f00::/16

5f00::/16 is the Segment Routing (SRv6) SIDs block.

Last updated 26 Oct 2026 from the IANA IPv6 Special-Purpose Address Registry

Short answer

IANA lists 5f00::/16 as “Segment Routing (SRv6) SIDs” (RFC 9602). It is not an ordinary public address.

Block5f00::/16
First – last5f00:: – 5f00:ffff:ffff:ffff:ffff:ffff:ffff:ffff
Sizea /16 (2^112 addresses)
Name in the registrySegment Routing (SRv6) SIDs
Defined inRFC 9602
Allocated2024-04
Valid as source / destinationTrue / True
ForwardableTrue
Globally reachableFalse

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Sources

  1. IANA IPv6 Special-Purpose Address Registry (CC0) · checked 26 Oct 2026
  2. RFC 9602