A fragment-based retransmission scheme with quality-of-service considerations for wireless networks

In order to satisfy quality-of-service requirements for real-time multimedia applications over wireless networks, IEEE 802.11e has been proposed to enhance wireless-access functionalities. In IEEE 802.11e, collisions occur frequently as the system load becomes heavy, and then, the latency for successfully transmitting data is lengthened seriously because of contention, handshaking, and backoff overheads for collision avoidance. In this paper, we propose a fragment-based retransmission (FBR) scheme with quality-of-service considerations for IEEE 802.11e-based wireless local area networks. Our FBR can be used in all proposed fragmentation-based schemes and greatly decrease redundant transmission overheads. By utilizing FBR, the retransmission delay will be significantly improved to conform strict time requirements for real-time multimedia applications. We develop an analytical model and a simulation model to investigate the performance of FBR. The capability of the proposed scheme is evaluated by a series of simulations, for which we have encouraging results. Copyright (c) 2011 John Wiley & Sons, Ltd.