Exploiting multimedia frame semantics and MAC-layer enhancements for QoS provisioning in IEEE 802.11e congested networks

Abstract

Wireless Local Area Networks (WLANs) supporting modern streaming multimedia applications constitute a very challenging and rapidly changing field of research. Towards implementing effective multimedia wireless networks, the IEEE has published the “state of the art” IEEE 802.11e standard, which introduced a QoS-aware MAC-layer along with a series of efficiency enhancements. However, it has been proven inadequate in handling multimedia traffic optimally in periods of congestion. For the efficient support of multimedia applications in high load situations, numerous mechanisms have emerged, most of them focusing on altering the static nature of resource allocation specified in IEEE 802.11e. Nevertheless, traffic characteristics must be taken into consideration in order to achieve the highest gains. In this paper, an application-aware MAC-layer mechanism is developed that exploits multimedia frame semantics and existing MAC-layer enhancements to adequately cope with high congestion situations in IEEE 802.11e infrastructure networks. The proposed algorithm makes use of existing acknowledgment policies and adaptive resource allocation techniques depending on multimedia frame significance. The effectiveness of the algorithm is proven by means of simulations, where its functionality is evaluated and compared with other existing schemes.