Performance measurements of TCP on a heterogeneous wireless multihop network

Future communication networks are expected to be heterogeneous consisting of different wireless systems such as cellular, WLAN, and Bluetooth systems. In this paper we examine the end-to-end performance of TCP protocol over IPv6 on a heterogenous multihop wireless network. We examine how the throughput is affected by using variable TCP window size, variable packet size, and variable datarates. Our results show that there is a certain window size which maximizes the TCP throughput. We found that sending TCP traffic with large packet sizes results in an improved end-to-end throughput. Similar results were obtained when sending TCP traffic at high datarates. The round trip time (RTT) measurements indicate that there is strong correlation between the RTT and window size. The experiments emphasize that with dynamic tuning of TCP window size, large improvements in throughput can be attained. The significance of this work is that it provides results obtained from a real network testbed.