TCP over IS-707

Mobile wireless Internet access services face a problem of mitigating the time-varying, correlated frame losses in fading radio channels. The losses may be compounded by detrimental interactions between separate error recovery mechanisms in the link and transport protocol layers. In this work we investigate by simulations the performance of TCP Reno over IS-707, a radio link protocol standard for spread spectrum digital cellular systems, and study the interactions of these protocols in the high loss regime. We show the improvement of TCP goodput by a fast RLP frame error recovery scheme based on using the IS-707 idle frames. We generalize the problem of characterizing the performance of user applications accessing the Internet over wireless data services by investigating the distributions of TCP goodput at multiple time scales, that give more insight than long-time averages. Results are presented for a range of frame error rates and normalized Doppler frequencies using a standard Markov model of a fading radio channel.