Improving reliable transport and handoff performance in cellular wireless networks

摘要: TCP is a reliable transport protocol tuned to perform well in traditional networks where congestion the primary cause of packet loss. However, with wireless links and mobile hosts incur significant losses due bit-errors hand-offs. This environment violates many assumptions made by TCP, causing degraded end-to-end performance. In this paper, we describe additions modifications standard Internet stack (TCP/IP) improve performance environments. The changes are network-layer software at base station host, preserve semantics TCP. One part modifications, called snoop module, caches packets performs local retransmissions across link alleviate problems caused high bit-error rates. second routing that enables low-latency handoff occur negligible data We have implemented new on testbed. Our experiments show system significantly more robust dealing unreliable than normal TCP; achieved throughput speedups up 20 times over regular latencies 10 shorter other protocols.