Abstract

Question

Is it possible to develop a delay-based congestion control algorithm for TCP that can be deployed on a network alongside TCP Reno and TCP Cubic?

Answer

Maybe – TCP BBR (“Bottleneck Bandwidth & RTT”) is one attempt:

  • Proposal from Google – measures RTT and bandwidth of the bottleneck link, directly sets congestion window

Used by YouTube in some cases, but highly experimental: Recent work by Ranysha Ware and Justine Sherry shows serious fairness problems with TCP BBR v1