Frame size effects on throughput and return traffic in Reliable Satellite Broadcast Transmission

This paper presents an overview of the Reliable Satellite Broadcast Transmission (RSBT) protocol and some performance results. RSBT was designed specifically for one hop point-to-multipoint satellite transmission. It does not use flow control, it does not give priority to retransmissions (which are based on Selective Repeat) and it does not restrict the frame size. The experiments presented here were focused on deriving throughput with various file sizes, the frame size effects on throughput and the return traffic. The results show that, as with most protocols, the throughput is far lower for small file transfers. The throughput is also affected by the frame size. However, careful selection of the frame size will result in very high throughput in most error rate scenarios. Although the experiments here involved up to 12 receivers, the return traffic results indicate that RSBT can serve much larger networks before the volume of return traffic becomes a real problem.