The Effects of Adaptive Error Correction on Satellite Optimized TCP

We show in this paper that the throughput of a performance enhancing proxy utilized in a DVB satellite channel suffers when an adaptive error correcting mechanism is introduced, resulting in a large percentage of the available bandwidth being wasted. To combat this, the addition of a simple bandwidth estimation scheme to the performance enhancing proxy is studied, and is shown to increase the average channel utilization to 95%. Additionally, it is shown that the introduction of a secondary TCP flow running in parallel with performance enhancing proxy (PEP) traffic can result in near 100% channel utilization when priority queues are used at the satellite gateway. Ultimately, tightly integrating performance enhancing proxies and satellite gateways is recommended as the best solution.