Multiplexing and resource allocation of VBR MPEG video traffic on ATM networks

This paper presents an analysis of the aggregate traffic of variable bit rate (VBR) MPEG-1 sources. The aggregate traffic was implemented by the superposition of different copies of a real sample obtained at the output of an MPEG coder. These copies were offset a random time interval, that was not forced to be a multiple of the interframe time. The study supposes that the coded information of each slice is packetized in cells and sent independently, and the cell stream is assumed to be suitably spaced during the slice interval. The study investigates the statistical properties of the sequence number of cells generated in a slice interval, discussing the influence of the of sources being multiplexed. The difficulties in modelling the aggregate process are discussed. A first approximation ARMA model is proposed. We present simulation results that describe the performance of the aggregate traffic at the input of a channel of limited capacity and buffer size. We comment on the trade-off between resource allocation and network performance, as well as, the degree of statistical multiplexing reached. These results serve to validate the model.