Dynamic and efficient tuning of IEEE 802.11 for multimedia applications

In order to exploit the properties of multimedia applications in IEEE 802.11-based wireless networks in more appropriate ways, we interest in the dynamic and efficient tuning of the MAC protocol by taking into account the inherent characteristics of this kind of applications. We focus here on the try limit parameter used at the 802.11 MAC layer to limit the number of retransmissions of a data frame by a source until the reception of a link-level acknowledgment from the destination. Based on analytical preliminaries, we determine the optimal value of this parameter in order to achieve an expected average end-to-end delay or a maximum packet loss rate. Moreover, an approximated value of the try limit parameter optimizing both QoS criteria (delay and packet loss rate) could also be obtained. Furthermore, these values are approximated dynamically using a simple algorithm that is easily implementable in 802.11 protocol.