Routing failure recovery with contention window adaptation in wireless networks

Due to contention through wireless shared channels, Real Bandwidth Delay Product (BDP) never reaches a value as big as one in wired network. Overshooting window problem is caused by congestion control algorithms which ultimately give poor throughput in Mobile Networks. The work concentrates to overcome the above mentioned problems. For this, the Round trip Time (RTT) is divided into two parts: a) Congestion RTT and b) Contention RTT. Contention RTT has no direct effect on BDP and BDP is determined by congestion RTT, if a link with worst contention status does not result in link breakage. Insufficient use of contention RTT results in Transmission Control Protocol (TCP) Congestion Window overshooting problem. Our work is to propose a new mechanism called Congestion Window Adaption with Routing failure Prevention that provide better and more accurate method of estimating the contention status. Congestion Window Adaptation-Retransmission Reduction (CWA-RR) is used to overcome routing failure. Based on this mechanism, our method prevents routing failure to limit the window size from overshooting. This is done by establishing connection between Transport layer, Network layer and MAC Layer. Results shows that proposed mechanism out-performs the conventional TCP and enhanced mechanism called TCP with contention control. © 2013, UK Simulation Society. All rights reserved.