Performance evaluation of flow fairness in proxy-based TCP for ad hoc networks

Ad hoc networks have technical problem of throughput degradation for long hop sessions, especially for long TCP sessions. One promising way to resolve this significant technical problem is proxy-based TCP which divides long end-to-end TCP session into several sub-sessions at proxy host(s). We have already revealed that original proxy-based TCP cannot improve TCP throughput easily. We also revealed that cause of throughput degradation is burst transmission of segments in each divided sub-session. We proposed adaptive rate control and intentional flow control which prevents burst transmission and improves TCP throughput. In this paper, we evaluate throughput performance of our proposed schemes in multiple flow case. Simulation results show that it still obtains better total throughput but has fairness problem for throughput of each flow. We investigates causes for this unfair condition of our proposed schemes and show future research directions for resolving this fairness issue.