C-Snoop: Cross Layer Approach to Improving TCP Performance over Wired and Wireless Networks

Summary TCP continues to be the most important transport layer communication protocol. In heterogeneous wired and wireless networks, however, the high packet loss rate over wireless links can trigger unnecessary execution of TCP congestion control algorithms, resulting in performance degradation. Several solutions have been proposed to address the known problems that TCP faces when running over wireless networks. Of those solutions, the localized link layer schemes, such as Snoop, SACK-Aware-Snoop and SNACK, has been shown to be the most effective. However in the wireless channel with high packet loss rate, these mechanisms do not work well. In this paper, we propose a new local retransmission scheme based on cross layer approach, called Cross-layer Snoop(C-Snoop) protocol, to solve the limitation of existing localized link layer schemes. From the simulation result, C-Snoop is proved to better TCP throughput and energy efficiency than existing mechanisms.