Behavior of TCP-Probing with Hand-offs

摘要

Performance of standard TCP is significantly degraded during hand-off periods of mobile communications. We show here that carefully designed probing mechanisms can cancel this incompetent behavior of TCP for a wide range of hand-off periods. We compare TCP Tahoe and Reno with TCP Probing under various scenarios of hand-off duration, propagation delay and mobility conditions of the user. We measure the goodput efficiency of data transfer as well as the energy efficiency of the protocols' mechanisms in terms of overhead and time. Our results show that TCP Probing demonstrates significant gains in both energy and throughput efficiency by avoiding unnecessary timeout extensions and retransmission of data which is likely to be lost due to hand-offs.