SIMULATION ANALYSIS OF A COMMUNICATION LINK WITH STATISTICALLY MULTIPLEXED BURSTY VOICE SOURCES

Variable bit rate (VBR) coding techniques have received great research interest as very promising tools for transmitting bursty multimedia t raffic with low bandwidth requirements over a communication link. Stat istically multiplexing the multimedia bursty traffic is a very efficie nt method to maximize the utilization of the link capacity. In this pa per, computer simulation techniques are used to analyze a rate-based a ccess control scheme for multimedia traffic such as voice traffic. It regulates the packetized bursty traffic at the user network interface (UNI) of the link. Using a suitable congestion measure, namely the mul tiplexer buffer length, the scheme dynamically controls the arrival ra te by switching the coder to a different compression ratio (i.e., chan ging the coding rate). VBR coding methods can be adaptively adjusted t o transmit at a lower rate with very little degradation in the voice q uality. The reported results prove that the scheme greatly improves th e link performance, in terms of reducing the probability of call block ing and enhancing the statistical multiplexing gain.