A Modified Approach to Enhance Performance of TCP Connection for Mobile Nodes in Wireless Scenario

In today’s time, the use of internet technology is become popular. Traditional TCP assumes congestion is only reason to packet loss in wireless scenario, whereas there are many other reasons of packet loss like link failure, congestion, bit error, signal fading etc. It also assumes that resulted packet loss during user or nodes movement from one subnet to another is also due to congestion in network and directly decrease the congestion window. To improve throughput performance of the Transmission control protocol, many variants were proposed i.e. TCP Reno, New Reno, Tahoe, Vegas, Westwood, Cubic etc. but they doesn’t sense then reason for packet loss either its due to congestion error or bit error. So in every case of packet loss it reduce congestion window and degrade the performance. If there is a bit error behind reason of packet loss then no need to reduce congestion window, just retransmit it. Proposed approach is aimed to improve the throughput performance of traditional TCP by differentiate issue of packet loss through either congestion or bit error, when it moves from one network to another. In our proposed work we will improve the throughput performance of TCP Vegas by sensing the issues of packet loss in wireless scenario. Proposed TCP variant uses the flag of TCP header to indicate the reason of packet loss and distinguish the issue from congestion. This work will improve the throughput performance results for modified TCP Vegas, after comparing Vegas and proposed TCP using network simulator NS-2.