TCP over wireless with link level error control: Analysis and design methodology

This paper considers the problem of supporting TCP, the Internet data transport protocol, over a lossy wireless link whose quality varies over time. In order to prevent throughput degradation, it is necessary to ``hide{''} th, losses and the time variations of the wireless link from TCP, A number of solutions to this problem have been proposed in previous studies, but their performance was studied on a purely experimental basis. This paper presents an approximate analysis, validated by computer simulations, for TCP performance over wireless links. The analysis provides the basis for a systematic approach to supporting TCP over wireless links. The specific case of a Rayleigh-faded wireless link and automatic repeat request-based link-layer recovery is considered for the purpose of illustration, The numerical results presented for this case show that a simple solution, that of using an appropriately designed link-layer error-recovery scheme, prevents excessive deterioration of TCP throughput on wireless links.