Rethinking Congestion Control for Cellular Networks

We propose Accel-Brake Control (ABC), a protocol that integrates a simple and deployable signaling scheme at cellular base stations with an endpoint mechanism to respond to these signals. The key idea is for the base station to enable each sender to achieve a computed target rate by marking each packet with an "accelerate" or "brake" notification, which causes the sender to either slightly increase or slightly reduce its congestion window. ABC is designed to rapidly acquire any capacity that opens up, a common occurrence in cellular networks, while responding promptly to congestion. It is also incrementally deployable using existing ECN infrastructure and can co-exist with legacy ECN routers. Preliminary results obtained over cellular network traces show that ABC outperforms prior approaches significantly.