TCP-Aware Backpressure Routing and Scheduling

Abstract

In this work, we explore the performance of backpressure routing and scheduling for TCP flows over wireless networks. TCP and backpressure are not compatible due to a mismatch between the congestion control mechanism of TCP and the queue size based routing and scheduling of the backpressure framework. We propose a TCP-aware backpressure routing and scheduling mechanism that takes into account the behavior of TCP flows. TCP-aware backpressure provides throughput optimality guarantees in the Lyapunov optimization framework, and gracefully combines TCP and backpressure without making any changes to the TCP protocol. The simulation results show that TCP-aware backpressure (i) improves the throughput of TCP flows significantly, (ii) provides fairness across competing TCP flows, and (iii) accommodates both TCP and non-TCP flows in a wireless network, and improves throughput of these flows without hurting fairness.