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 traffic with low bandwidth requirements over a communication link. Statistically multiplexing the multimedia bursty traffic is a very efficient method to maximize the utilization of the link capacity. In this paper, computer simulation techniques are used to analyze a rate-based access 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 multiplexer buffer length, the scheme dynamically controls the arrival rate by switching the coder to a different compression ratio (i.e., changing the coding rate). VBR coding methods can be adaptively adjusted to transmit at a lower rate with very little degradation in the voice quality. The reported results prove that the scheme greatly improves the link performance, in terms of reducing the probability of call blocking and enhancing the statistical multiplexing gain.