Advanced Satellite Infrastructures in Future Global Grid Computing Network Solutions to Compensate Delivery Delay

Abstract

Scientific equipment in remote locations may be integrated in a grid network by means of satellite links. When the grid is an Internet overlay network, TCP-like congestion control protocols tend to introduce large delays and to achieve poor bandwidth utilization during the start-up phase due to the large bandwidth-delay product of the satellite link. Recent studies demonstrate that the loss of performance is high when a demand assignment multiple access (DAMA) scheme is adopted to manage satellite resources. To overcome this problem, we propose a new mechanism based on Quick Start, a recent IETF recommendation, to enhance the startup performance of data and streaming flows. We show, by means of extensive simulations, that our modifications to enable a QS-based DAMA algorithm allow the initial end-to-end delay to be significantly reduced and the queue length in transmitting nodes stabilized. Moreover, our results point out that the start-up delay is quite independent of the flow rate, which makes this algorithm suitable to the high bitrate required by grid computing applications.