Contention avoidance mechanism for TCP in mobile ad hoc network

Transmission Control Protocol (TCP) is the de-facto standard protocol that is responsible for the transmission of around 90% of the Internet traffic. TCP was originally designed for wired network where buffer overflow induced packet loss dominates. However, this type of packet loss is rare in ad hoc network and packet drop due to link-layer contention dominates. Ignoring this special characteristic leads to poor performance of TCP. In this paper, we provide an overview on spatial contention and discuss the impact of contention on TCP performance. Afterwards, a survey on the recent proposals that aim to alleviate the effects of spatial contention on TCP is conducted, placing special emphasis on techniques that preserve end-to-end semantic. Finally, we propose our contention avoidance mechanism that adapts the sending rate and enhances TCP performance. The proposed mechanism was verified and validated be comparing our result to output obtained from real test bed. Finally, it is expected that TCP with our contention avoidance mechanism will gain a significant improvement.