Performance Guarantees on ATM Networks

Recent developments in ATM technology has made multiplexing of a wide range of traffic with diverse performance requirements important. The statistical multiplexing of several traffic types such as voice, video and data can lead to network congestion thus violating the quality of service (QOS) guarantees. In order to meet the performance requirements of the applications an efficient transport protocol and congestion control mechanism becomes necessary. We propose a transport mechanism for guaranteeing application required QOS requirements over an ATM network. Leaky-bucket congestion control scheme is used as the traffic policing mechanism. Source characterization of voice and video are modeled as Markov Modulated Poisson Processes (MMPP) and the proposed transport mechanism is evaluated by simulation on a single and multihop network with multimedia traffic. The performance of the scheme is examined as a function of source characteristics and the effect of statistical multiplexing is also investigated. The results indicate that the leaky-bucket scheme and statistical multiplexing are more effective for bursty traffic. This calls for a dynamic control mechanism to achieve optimal system utilization with guaranteed QOS.