The Rx Hex

Because we like to run the AFS distributed3le system on dataless clients at our homes, it is vital that the meager bandwidth available be used effectively. This makes Ru, the AFS remote procedure call package, a critical link in the overall system performance chain. In this paper, we report on our progress in adapting R.u to networks characterized by low bandwidth, high delay, or variable round-trip time. When we started, the throughput deilivered by Rx over dialup networks was approxitnatei‘y Zero, due to fragmentation and congestion collapse. By making extensive modijications to Rx, focusing on congestion avoidance and control and header compression, we have accompli,shed our throughput objectives and made Rx a high-performing transport layer.