Summary

  • The IETF document feed recorded draft-xu-idr-fare at 04:45 UTC on 17 August; the current public text is draft-xu-idr-fare-07, dated 16 August 2026.
  • The draft describes a Path Bandwidth Extended Community for BGP-based adaptive routing in three-stage and five-stage CLOS fabrics, and conditions weighted ECMP on every equal-cost route carrying the information.

The IETF Datatracker record presents FARE as an Internet-Draft and explicitly says such a document is not endorsed by the IETF and has no formal standing in its standards process. The version -07 text is dated 16 August and is intended for Standards Track consideration. Those labels matter: the update is a design input, not a new BGP capability that operators can assume exists.

FARE proposes carrying end-to-end path bandwidth in a new BGP extended community. It describes this as an input to adaptive, weighted ECMP decisions in 3-stage and 5-stage CLOS fabrics. The text is explicit that an operator should not perform path-bandwidth weighted ECMP unless every equal-cost route for the relevant prefix carries the community. That is not an implementation detail; it is the draft’s guard against comparing informed routes with routes that lack the same signal.

The document discusses data-centre fabrics and high-throughput workloads, but it makes no evidence claim about a particular fabric, workload, latency gain, or congestion result. It also says adaptive routing does not solve last-hop incast, for which congestion control remains necessary. Version -07 states an expiry date of 17 February 2027 unless it advances.