TCP over mobile ad-hoc access networks.

摘要

The rapid advancement in portable computing platforms and wireless communication technology has led to significant interest in the design and development of protocols for instantly deployable wireless networks, often referred to as MANET: "Mobile Ad-Hoc Network". This thesis concentrates on the transmission layer, which is mostly implemented by TCP (Transmission Control Protocol). TCP suffers a significant drop in its throughput when it runs on a MANET. This significant TCP throughput drop is mainly because of the TCP implicit assumption that any packet loss is due to congestion, which causes TCP to invoke the congestion control algorithms. This assumption is true for the wired network, but not true for the MANET. To the best of our knowledge this research is the first research that discuss, propose and evaluate transmission control scheme for a MANET connected to the wired network (MANET as Access Network). Our scheme consists of three protocols, the TCP protocol on the wired network, the Snoop protocol on the base station and the ATCP protocol on the MANET. The simulation results show that our scheme was able to improve the TCP end-to-end connection throughput without requiring changes to the TCP stack on the fixed host(s), limiting the changes to the base station and the mobile host(s). This will make deploying such a scheme much easier, as it does not require re-compiling and re-linking existing applications.