A comprehensive study of cross - layer approaches for improving TCP performance in wireless networks

TCP- Transmission Control Protocol is a connection oriented and reliable transport layer protocol. TCP was initially used for process-to-process communication in wired networks. When TCP is used with wireless networks, especially with the wireless mobile adhoc networks, a significant amount of performance degradation can be noticed. The main reasons are route failures, channel losses and channel contention issues. This paper focuses on cross-layer approaches to improve TCP´s performance. In cross-layer approaches, the lower layers provide feedback - decision making information to the transport layer. Transport layer uses this information to differentiate congestion loss and non congestion loss. Approaches are classified into three categories for route failures, channel losses and channel contention issues.