TCP-Aware Backpressure Routing and Scheduling

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 that takes into account the behavior of TCP flows. TCP-aware backpressure (i) provides throughput optimality guarantees in the Lyapunov optimization framework, (ii) gracefully combines TCP and backpressure without making any changes to the TCP protocol, (iii) improves the throughput of TCP flows significantly, and (iv) provides fairness across competing TCP flows

Achieving Congestion Diversity in Wireless Ad-hoc Networks

Abstract—This work presents the Congestion Diversity Protocol (CDP), a routing protocol for multi-hop wireless networks that combines important aspects of shortest-path and backpressure routing to achieve improved end-end delay performance. In particular, CDP delivers lower end-to-end delay and fewer packet drops than existing routing protocols while maintaining equivalent throughput. This paper reports on a practical (hardware and software) implementation of CDP in an indoor WiFi network consisting of 12 802.11g nodes. This small test-bed enables an imperical comparison of CDP’s performance against a set of state of the art protocols which include both congestion unaware and congestion aware routing protocols. In most topologies and scenarios we consider, CDP provides improvements for UDP traffic with respect to both end-end delay and throughput over the existing protocols. I