Wireless Transport Layer Congestion Control Evaluation

Abstract

The performance of transport layer protocols can be affected differently due to wireless congestion, as opposed to network congestion. Using an active network evaluation strategy in a real world test-bed experiment, the Transport Control Protocol TCP, Datagram Congestion Control Protocol DCCP, and Stream Control Transport Protocol SCTP were evaluated to determine their effectiveness in terms of throughput, fairness, and smoothness. Though TCP's fairness was shown to suffer in wireless congestion, the results showed that it still outperforms the alternative protocols in both wireless congestion, and network congestion. In terms of smoothness, the TCP-like congestion control algorithm of DCCP did outperform TCP in wireless congestion, but at the expense of throughput and ensuing fairness. SCTP's congestion control algorithm was also found to provide better smoothness in wireless congestion. In fact, it provided smoother throughput performance than in the network congestion.