Improving the performance in multimedia streaming networks: a differentiated service approach

The best-effort service model supported by the Internet, works very well with conventional Internet applications like file transfer, electronic mail, and Web browsing because of their ability to cope with packet losses and varying packet delays, but does not guarantee bandwidth, low latency and timely delivery of packets. But Internet, with the recent growth trends in bandwidth availability, is evolving in the multimedia communication system of the future and so is absolutely necessary to cope with the basic problems of the best-effort service model when applied for media streaming applications. In detail, multimedia applications with real-time properties require tight guarantees in terms of end-to-end packet delay and packet loss. In order to meet these requirements and manage the multitude of applications such as streaming video, voice over IP, e-commerce and others, a network requires quality of service (QoS) in addition to best-effort service. Different applications have varying needs for delay, delay variation (jitter), bandwidth, packet loss, and availability. These parameters form the basis of QoS. The IP network should be designed to provide the requisite QoS to applications. This paper presents a successful approach in implementing end-to-end QoS according to the Differentiated Service model to achieve significant improvements in the performance of high-traffic multimedia networks. A complete framework of QoS DiffServ facilities has been presented for deployment of performance-aware multimedia streaming networks.