Real-Time Traffic Transmission over the Internet

Multimedia applications require the transmission of real-time streams over a network. These streams often exhibit variable band-width requirements, and require high bandwidth and guarantees from the network. This creates problems when such streams are delivered over the Internet. To solve these problems, recently, a small set of differentiated services has been introduced. Among these, Premium Service is suitable for real-time transmissions. It uses a bandwidth allocation mechanism (BAM) based on the trac peak rate. Since the bandwidth requirement of a video stream can be quite variable, this can result in a high cost to the user and an inecient use of network bandwidth. In this paper we introduce a BAM that can increase bandwidth utilization and decrease the allocated bandwidth without aecting the QoS of the delivered real-time stream and without introducing any modification in the Premium Service. We also introduce several frame dropping mechanisms that further reduce bandwidth consumption subject to a QoS constraint when coupled with the above BAM. The proposed BAM and the heuristics algorithms are evaluated using Motion JPEG and MPEG videos and are shown to be effective in reducing bandwidth requirements