Tcp over Wireless

In a wired network, most packet losses are due to congestion. TCP exploits this characteristic of wired networks and is tuned to perform well in such an environment. But in a wireless environment, losses due to errors over the wireless hop also contribute signiicantly to the cumulative packet losses. If TCP is used ov er a wireless link, then its performance is severely degraded. In this paper, we have studied the performance of TCP-Tahoe, TCP-Reno and TCP-Vegas over a wireless network in the presence and absence of local error recovery at the base station. The performance of the various TCP protocols over an equivalent wired network has been included in the comparison. The eeect of packet size variation has also been studied. The error model uses exponentially distributed time intervals between consecutive errors introduced over the wireless link.