S.P.Valli and K.M.Mehata, B.S.Abdur Rahman University, India

Transmission Control Protocol (TCP) is a connection oriented end-end reliable byte stream transport layer protocol. It is widely used in the Internet.TCP is fine tuned to perform well in wired networks. However the performance degrades in mobile ad hoc networks. This is due to the characteristics specific to wireless networks, such as signal fading, mobility, unavailability of routes. This leads to loss of packets which may arise either from congestion or due to other non-congestion events. However TCP assumes every loss as loss due to congestion and invokes the congestion control procedures. TCP reduces congestion window in response, causing unne-cessary degradation in throughput. In mobile ad hoc networks multi-hop path forwarding fur-ther worsens the packet loss and throughput. To understand the TCP behavior and improve the TCP performance over mobile ad hoc networks considerable research has been carried out. As the research is still active in this area a comprehensive and in-depth study on the TCP through-put and the various parameters that degrade the performance of TCP have been analyzed. The analysis is done using simulations in Qualnet 5.0

TCP, Ad hoc networks, Retransmissions, Throughput.