Network-level loss control schemes for streaming video

Packet loss due to network congestion causes degradation in the quality of networked video transmitted over IP networks. Buffer management and packet scheduling are two key router-based quality of service (QoS) control techniques. Existing buffer management mechanisms mainly focus on preventing network congestion in order to reduce packet loss. However, a low packet loss ratio by itself does not necessarily translate to high video quality, so these methods, by themselves, do not ensure user-expected video quality. We proposed an alternative buffer management approach, called FDDT, which focuses on improving user-expected video quality, rather than just aiming at reducing packet loss (Ito, M.R. and Bai, Y., 8th IEEE Int. Conf. on Commun. Systems, 2002). Most packet scheduling mechanisms are designed to provide delay guarantees. We have shown that packet scheduling is a viable and attractive option to help provide further loss guarantees (Bai and Ito, 10th Int. Conf. on Telecom., 2003). The packet scheduling scheme is called MPAPS. This paper compares the performance of FDDT, MPAPS, and a combination of FDDT and MPAPS based on video quality, service fairness and network efficiency.