A Segregation Based MAC Protocol for Real-Time Multimedia Traffic in WLANs

Providing quality of service (QoS) for multimedia applications in wireless local area networks (WLAN) is a very challenging task. This is mainly due to the real-time nature of multimedia traffic such as voice and video applications, that are sensitive to delay and jitter. QoS guarantees for real-time traffic must be imposed in WLAN so as to enable WLAN users to fully benefit from multimedia applications. The current medium access control (MAC) protocol that is widely used is the legacy IEEE 802.11, but this protocol does not support QoS for realtime traffic. To enhance the legacy 802.11, the IEEE 802.11e protocol was introduced to support QoS through prioritization of traffic. The 802.11e introduces a new co-ordination function known as hybrid coordination function (HCF). In this paper we study the performance of multimedia traffic in the legacy 802.11 and 802.11e and propose a technique to improve realtime traffic in multimedia applications by traffic segregation. We show that segregation of multimedia traffic improves delay and jitter performance of real-time traffic.