A strategy for fair coexistence of loss and delay-based congestion control algorithms

Delay-based TCP variants have attracted a large amount of attention in the networking community because of their ability to efficiently use network resources, control queuing delays, exhibit virtually zero packet loss, etc. One major issue that discourages the wider deployment of delay-based TCP variants is their inability to co-exist fairly with standard loss-based TCP. In this note we propose a simple mechanism that allows delay- and loss-based (AIMD) TCP flows to compete fairly with each other. Further, our approach ensures that delay-based flows automatically (and swiftly) switch to a low-delay regime if no loss-based flows are present. We provide analytical and simulation results to validate presented algorithm.