Satellite communications link adaptation design and interaction with TCP

The dynamic allocation algorithm is designed where each link´s traffic is reported as the number of IP packets in a variety of queues. There can be a number of queues corresponding to differentiated traffic, but there is no mechanism for determining if more than a single TCP flow is generating the traffic within a single differentiated queue. The interaction between dynamic allocation algorithms and TCP is investigated and illustrated in this paper. The goal is to help dynamic link adaptation designer´s select system parameters that are compatible with TCP and geosynchronous satellite links. In general, quickly varying the link data rate over a wide range of values does not maximize system throughput. However, dynamic link adaptation leads to greater throughput than static robust links if bursts of higher data rate are granted when the channel can support such an increase. In addition, the results in this paper show that the manner in which the dynamic allocation algorithm transitions between states affect the system performance.