Differentiation of Wireless and Congestion Losses in TCP

Abstract

TCP is the most commonly used data transfer protocol. It assumes every packet loss to be congestion loss and reduces the sending rate. This will decrease the sender's throughput when there is an appreciable rate of packet loss due to link error and not due to congestion. This issue is significant for wireless links. We present an extension of TCP-Casablanca, which improves TCP performance over wireless links. A new discriminator is proposed that not only differentiates congestion and wireless losses, but also identifies the congestion level in the network, i.e., whether the network is lightly congested or heavily congested and throttles the sender's rate according to the congestion level in the network.