Cross-layer Quality of Service for video wireless multimedia delivery: some challenges and principles

Providing cross-layer quality of service (QoS) for wireless multimedia delivery is challenging task which has attracted intensive research over the years. A fundamental problem in this area is how to map QoS criterion at different layers and optimum QoS across the layers. We present end-to-end QoS architecture for multimedia delivery as well as QoS metrics over wireless links together with channel model and QoS evolution. Then, we invoke a cross-layer design for multimedia scheduling at the data link layer, with each user employing adaptive modulation and coding (AMC) at the physical layer. The cross layer design provides lowcomplexity implementation and analysis as well as service isolation and scalability. Also, the QoS of a certain user in terms of its throughput, packet bit rate and average delay for a given bandwidth allocation is provided. Key-words: QoS cross-layer design, adaptive modulation and coding (AMC), medium access control (MAC)