TCP-BuS: Improving TCP performance in wireless ad hoc networks

Reliable data transmission over wireless multi-hop network, called ad hoc network, has proven to be non-trivial. TCP (Transmission Control Protocol), widely used end-to-end reliable transport protocol in wired network, is not entirely suitable when applied to wireless ad hoc network due to TCP's congestion control schemes. In particular, TCP at the source considers the network is congested when detecting packet losses or timeouts. However, in a wireless ad hoc network, when a route disconnection occurs because of node movement, the network mistakens this as a congestion. Therefore, the conventional TCP congestion control mechanism cannot be applied, because a route disconnection must be handled differently from network congestion. In this paper, we propose a new mechanism that improves TCP performance in a wireless ad hoc network where each node can buffer packets during a route disconnection and reestablishment. Additionally, we incorporate new measures to deal with the reliable transmission of important control messages. Our simulation results further confirmed these advantages.