Mobile-Host-Centric Transport Protocol for EAST Experiment

Some physics researchers retrieve EAST experiment data using TCP in wireless local area network (WLAN). TCP is the most commonly used transport control protocol. It assumes that every packet loss is caused by network congestion and invokes congestion control and avoidance. TCP´s blind congestion control results in degraded performance in the lossy wireless networks. In a wireless network, mobile hosts have first-hand knowledge of the lossy wireless links; therefore, mobile stations can make better transmission control based on the known status of wireless link. In this paper, we proposed a new mobile-host-centric transport protocol (MCP) that integrates the characteristics of sender-centric and receiver-centric transport control schemes. MCP shifts most control policies to the mobile host side. The general behavior of MCP is similar to the TCP, but by utilizing the local information collecting from the mobile node in WLAN, MCP allows for better congestion control and loss recovery. Specifically, we designed a cross-layer implementation of MCP and ran it on NS-2. With valuable MAC (Medium Access Control) layer feedback information, MCP is able to distinguish packet loss caused by wireless random errors from network congestion more clearly and can perform a more accurate congestion control. We did extensive simulations of MCP on various WLAN scenarios, and the results show that the throughput of MCP with cross-layer feedback is higher than that of TCP Reno and Westwood.