The design and performance of Mobile TCP for wireless networks

Article type: Research Article

Authors: Haas, Zygmunt J. | Warkhedi, Abhijit

Affiliations: School of Electrical Engineering, Cornell University, Ithaca, NY 14853‐2801, USA E‐mail: haas@ece.cornell.edu, warkhedi@cisco.com

Abstract: In this paper, we propose a novel approach to reduce the wireless communication overhead associated with the transport layer. Portability is a key element of mobile computing. As mobile devices shrink in terms of size and weight, their computing capabilities are also reduced, constrained by battery capacity. To sustain a good performance level of mobile applications, we devise a solution that reduces the processing complexity on computing‐limited mobile devices. Additionally, we aim to minimize the use of wireless resources to further improve performance. Specifically, we develop a streamlined protocol architecture, Mobile TCP (MTCP), that achieves the elimination of IP processing on the wireless segment of the TCP connection. MTCP operates over a single hop wireless link, and, consequently, it eliminates the unnecessary overhead placed on mobile devices, such as the TCP congestion control mechanisms. In addition, we investigate the impact of streamlining the socket layer on offloading the processing overhead. Our experimental results indicate a substantial improvement in the efficiency of protocol processing. For instance, results show that the MTCP processing time per packet is approximately only one fourth that of TCP and the use of CPU resources is reduced by up to 50%. Furthermore, the protocol incorporates various robust, yet simple, loss recovery techniques to considerably improve the throughput in lossy wireless conditions.

Journal: Journal of High Speed Networks, vol. 10, no. 3, pp. 187-207, 2001