Synchronizing TCP with Block Acknowledgement over Multi-hop Wireless Networks

Abstract

While TCP is highly successful in the wire-line Internet, its performance fast degrades as the number of hops increases in multihop wireless networks. It is due to not only the half-duplex nature of the wireless medium, but also the two-way feature of TCP. In order to improve TCP performance in multihop wireless networks, we pay attention to its cumulative ACK policy. Systematically exploiting the redundant nature of the ACK policy, we replace some ACKs with data packets. We call this scheme block acknowledgement. In consequence, the throughput is significantly increased at the slight weakening of ACK reliability. We evaluate the performance of TCP with and without the block acknowledgement through simulations and analysis.