<title>Importance of multiple correlation of variable-bit-rate video traffic in ATM traffic engineering</title>

Abstract

Variable bit rate (VBR) video traffic makes crucial impact on ATM network performance, design and management due to its wide bandwidth, high burstiness and strong correlation. Previous studies focus on the bandwidth distribution and autocorrelation of VBR video sources. We investigate the importance of the multiple correlation of VBR video traffic in ATM buffering systems. We choose two models to generate VBR video traffic, one is auto-regressive (AR) model, and the other is discrete auto-regressive (DAR) model. The two models have same bandwidth distribution and auto-correlation but different multiple correlation. Numerical experiments are taken to compare the queuing performance of a finite ATM buffer loaded with AR, DAR sources. Results show (1) cell loss rate (CLR) of those two input sources are very closely when CLR is large; (2) the error between them becomes more evident as CLR decreases; (3) this error becomes non- negligible when CLR less than 10<SUP>-5</SUP> (occurs in ATM practice). Our study shows that the multiple correlation of VBR video traffic take an important impact on queuing performance in realistic network applications, which must be taken account of to model VBR video sources and perform more reliable queuing analysis.