Abstract
A low bit-rate ZigBee-based sensor network carrying scalable video streams will be considered. A cross-layer priority algorithm that combines the state of the channel and the quality of the video traffic will be suggested to optimize the required quality of service of the video streams. The proposed algorithm prioritizes the transport of the basic frames, and thus minimizes the carried enhancement orphan frames. It also avoids transmitting the enhancement frames related to a dropped basic frame. A noticeable improvement in the end-to-end delay of the video stream was achieved, an increase in the carried base frames, and a decrease in the orphan frames provided both an enhanced quality of the received video stream and an improvement in the channel utilization.