PCP: Efficient Endpoint Congestion Control

In this paper, we present the design, implementation, and evaluation of a novel endpoint congestion control system that achieves near-optimal performance in all likely circumstances. Our approach, called the Probe Control Protocol (PCP), emulates network-based control by using explicit short probes to test and temporarily acquire available bandwidth. Like TCP, PCP requires no network support beyond plain FIFO queues. Our initial experiments show that PCP, unlike TCP, achieves rapid startup, small queues, and low loss rates, and that the efficiency of our approach does not compromise eventual fairness and stability. Further, PCP is compatible with sharing links with legacy TCP hosts, making it feasible to deploy.