A critical design issue of TCP is its congestion control that allows the protocol to adjust the end-to-end communication rate to the bandwidth on the bottleneck link. However, TCP congestion control may function poorly in high bandwidthdelay product networks because of its slow response with large congestion windows. In this paper, we propose an improved version of TCP Vegas called Quick Vegas, in which we present an efficient congestion window control algorithm for a TCP source. Our algorithm is based on the increment history and estimated amount of extra data to update the congestion window intelligently. Simulation results show that Quick Vegas significantly improve the performance of connections as well as remain fair and stable when the bandwidth-delay product increases.