Resource allocation scheme for video transmission with proper channel rate in ATM

Abstract

This paper presents resource allocation problem for MPEG (Moving Picture Experts Group)-based real time variable bit rate (VBR) video transmission over asynchronous transfer mode (ATM) networks. The real time video MPEG traffic such as video conferencing has VBR traffic property which is very sensitive to delay. Given ATM switch capacity, we consider video transmission and receiving system with multiple users and multiple traffic (encoded and decoded cells). Multiple video sources are multiplexed into an ATM switch to transmit cells over ATM network. Under these circumstance, this study is interested in resource allocation of the required channel bandwidth for each video source such that encoder rate and decoder buffer occupancy are maintained at target level. With mathematical formulations, we propose two cases of algorithm for efficient bandwidth allocation. One is that the priorities among each source are given distinctly and the other is that no priority is given at connection setup phase. In the two cases of algorithm, we devise different rules to give priorities among sources. Then, we analyze the effects of different rules using two performance matrics : the cell compression rate over encoder target rate and the gap in decoder buffer at each frame period. We also compare different rules. Numerical results are provided with different levels of system delay, each buffer size, ATM switch capacity, resource utilization rate, and different number of multiplexed sources.