Ofer Hadar

Improvements in telecommunication and computer technologies have made integrated services packet-switched networks possible. It is expected that a significant portion of future networks will carry prerecorded video and that traffic in applications such as video on demand (VoD) will include high-fidelity audio, short multimedia clips, and full-length movies. In this paper we study the effect of video rate smoothing, of prerecorded VBR sources, on network utilization and admission control of a VoD system, such that the end users receive a satisfactory service. The enhancement piecewise constant rate transmission and transport (e-PCRTT) algorithm is used as the smoothing algorithm, which utilizes equal size intervals. The effect of smoothing on the statistical characteristics of multiplexed video streams is explored. We found that synchronization between the smoothing intervals can significantly improve the efficiency of the smoothing process by reducing the number of bandwidth changes and the rate variability of the multiplexed stream. In this paper we propose an admission control policy in which a bandwidth rate-plan is negotiated at stream initiation. The algorithm is evaluated via simulation for the VoD scenario.