Cross-layer optimization for SVC video delivery over the IEEE 802.11e wireless networks

The Scalable Video Coding (SVC) standard extends the H.264/AVC with scalability support and is effective to adapt bitrate to the time-varying wireless channel bandwidth. In this paper, we propose a cross-layer optimization scheme, which includes packet prioritization and QoS mapping, for the delivery of SVC over the IEEE 802.11e wireless networks. The proposed structure enables interaction among different network layers, providing differentiated services for video packets. Our cross-layer optimization performs with the following information: (i) SVC packet prioritization at the application layer, (ii) service differentiation at the MAC layer, and (iii) interface queue (IFQ) occupation status at the link layer. We formulate the QoS mapping problem as a joint optimization of access category (AC) assignment and IFQ control. A novel and efficient solution is proposed to reduce the computational complexity of the joint optimization problem. Simulation results show that the proposed approach achieves notable improvement when compared to conventional methods.