An experimental analysis of rate-based and window-based transmission mechanisms over simulated space-Internet links

There is an urgent need for finding an optimal transmission mechanism in the space-based Internet. This paper presents an experimental analysis of the throughput performance and transmission behavior for the rate-based and window-based congestion control mechanisms in a simulated small-satellite environment using a PC-based test-bed. The experimental analysis revealed that the traffic shaping mechanism of a rate-based transmission is more effective than the bursting flow of a window-based mechanism in error-prone space environment with a long link delay. The window-based transmission mechanisms show performance degradation due to traffic bursts and frequent packet retransmissions caused by their ACK-clocked congestion control. Pure rate-control is preferable to other mechanisms in space when bandwidth reservation is available.