A novel packet priority scheme and mapping algorithm for scalable video over wireless ad-hoc networks

Scalable video coding (SVC) can provide quality video delivery via layered structures of multi-dimensional scalabilities in error-prone transmission environments such as wireless LANs. However, further enhancement of wireless scalable video delivery demands a good cross-layer design. Considering both temporal and quality scalabilities, this paper proposes a novel cross-layer design called TLO+MPM, where TLO is a temporal-layer-oriented priority scheme of video packets in the Application layer, and MPM is a multi-power-mapping algorithm among the access category (AC) queues in the 802.11 MAC layer, which provides multi-branch mapping probability functions of the AC_VI (AC for video) queue length based on TLO-specific branch powers. The experimental results show that our proposed TLO+MPM design outperforms the existing ones, including SI+SBED, 3C+SM and EDCA, for both the non-real-time and real-time scenarios. The gains of TLO+MPM over the others are amplified particularly in the real-time scenario.