Influence of adaptive RTS/CTS retransmissions on TCP in wireless and ad-hoc networks

• Venue: ISCC '03 Proceedings of the Eighth IEEE International Symposium on Computers and Communications
• Year: 2003

The trend of wireless networking is growing. This is dueto the success of IEEE 802.11 WLAN technology which allows the extension of local area networks by mobile stationsand establishing of ad-hoc networks. The latter does notneed any pre-installed infrastructure. Nodes communicatedirectly or the traffic is relayed over intermediate wirelessnodes.While there are only few nodes the performance of thenetwork is acceptable, but with increasing number of nodesthe performance of the network decreases. If TCP is usedadditional performance degradation is expected. However,TCP is necessary since most applications and applicationlevel protocols are based on it. The poor performance ofTCP in wireless networks has several reasons, especiallythe communication medium with high bit error rates (BER)and TCP's optimization on fixed networks.In this paper, we present an analysis of TCP's performance in wireless and ad-hoc networks. We emphasizethe role of MAC layer retransmissions without breaking theend-to-end semantic of TCP. For this, we introduce the dynamic short retry limit which allows the adaptation of RT-S/CTS retransmissions.