The traditional TCP congestion control mechanism encounters a number of new problems and suffers in poor performance. In traditional TCP congestion control, slow start results in poor performance. During slow start the number of TCP segments transmitted per unit time is considerably small compared to the capacity of the Network. It increases gradually according to the RTT. In this paper, an attempt is made to increase the performance of the TCP by introducing a two new technique called Adaptive Fair Share of Congestion window size (AFSCOW) and Smart Start (SS). AFSCOW can be used for the new TCP connections emerging in the end systems having same sender and receiver. For an emerging new application in the sener the window size can be determined as the total of the current window sizes of the existing application divided by the total number of application including the new emerging application. In Fast Start the number of TCP segments transmitted is not doubled but it is increased three times the older window size which shows the optimum use network resources within minimumRTT.

Key words:TCP, Congestion Window size, Link Utilization, Bandwidth Sharing, RoundTripTime (RTT).