Scheduling Video Stream Transmissions for Distributed Playback over Mobile Cellular Networks

In this paper, we address the issues in mobile bandwidth scheduling for video stream transmissions in a distributed video player system supported on cellular network. Two important concerns in the design of the scheduling algorithms are fairness in services and adaptability to the changing playback condition of individual video. In this paper, we present the Buffer Sensitive Rate-Based (BSRB) algorithm which provides a fair scheduling scheme to serve video playback requests, while maximizing the performance of individual playback. Adaptability is an important issue in video streaming over mobile cellular networks, since different clients may be subjected to different probabilities of communication errors and also the workload in each cell is highly dynamic due to the mobility of clients. In BSRB, the amount of bandwidth allocated to serve a video request depends on the buffer level of the requesting client, and the expected and minimum bandwidth requirements of the video. It is expected that by maintaining a high video buffer level at a client, the quality of the playbacks can be maintained and its performance will be more adaptive to the changing playback conditions. In addition, by employing the rate-based policy in BSRB, the performance of the requests will be less affected by the poor performance of a single client and hence fair services can be provided to the clients. Extensive simulation experiments have been performed to investigate the performance characteristics of the proposed BSRB algorithm as comparing with other algorithms under different system settings and network failure probabilities.