TY - JOUR T1 - An Opportunistic Routing Protocol for Wireless Mesh Networks to Improve TCP Performance AU - Ananthi, N. AU - Sudha, S. JO - International Journal of Soft Computing VL - 9 IS - 6 SP - 401 EP - 407 PY - 2014 DA - 2001/08/19 SN - 1816-9503 DO - ijscomp.2014.401.407 UR - https://makhillpublications.co/view-article.php?doi=ijscomp.2014.401.407 KW - Serial timeouts KW -loss recovery KW -retry limit KW -fast retransmit KW -intermittent connectivity KW -bit error rate KW -round trip time AB - Multi path routing protocol such as AOMDV establishes multiple link disjoint paths between source and destination that provides reliable, fault tolerant network and improves TCP performance over multi hop WMNs. But TCP misinterprets the frequent link failure and wireless channel errors as congestion and slow starts the window size, even during the availability of alternate paths in the routing table. Presented in this study is the solution to the problem that arises when the TCP/IP protocol suite is used to provide internet connectivity through mobile terminals over emerging 802.11 wireless links. Taking into consideration the strong drive towards wireless Internet access through mobile terminals, the problem of frequent disconnections causing serial timeouts is examined and analysed with the help of extensive simulations. After a detailed review of wireless link loss recovery mechanism and identification of related problems, a new scheme with modifications at link layer and transport layer is proposed. The proposed modifications which depend on interaction between two layers: reduce the idle time before transmission at TCP by preventing timeout occurrences and decouple the congestion control from recovery of the losses due to link failure. Results of simulation based experiments demonstrate considerable performance improvement with the proposed modifications over the conventional TCP when a wireless sender is experiencing frequent link failures. ER -