QoS enhancement methods for MPEG video transmission on the Internet

With the advances in services using the present Internet, an increasing demand for video-on-demand (VoD) on the Internet may be expected in the near future. However, because of the best-effort characteristics of the Internet, it is important to suppress the degradation of communication quality caused by packet dropping when Internet traffic is congested. This paper focuses on MPEG transmission over the Internet, and suitable control mechanisms are established for an acceptable quality of service (QoS) improvement through detailed evaluation. Packets are classified using a frame-based scheme. The server applies the proposed end-to-end control scheme and shuffles the order of packets to avoid burst dropping, and may omit selected packets belonging to certain frames prior to forwarding. At the intermediate routers, transferred packets are transmitted according to round robin (RR) or weighted round robin (WRR) scheduling, and are dropped statistically using selective random early detection (RED) corresponding to frame attributes when there is congestion. We evaluate the proposed transmission method using both simulation of transmission characteristics and empirical measurements of picture quality.