A method for analysing multimedia protocol performance

Performance analysis derived from a formal specification of a multimedia protocol provides important information on the performance characteristics of a multimedia system before implementation. The major problem of existing performance methodology is the lack of feasibility in time-dependent and functional behaviours, as well as statistical traffic characteristics for distributed multimedia systems. The internationally standardised Formal Description Technique, Estelle, does not have enough expressive power to specify the time-dependent performance characteristics of a multimedia system. To address this limitation of Estelle, we have developed a variant of Estelle, called Time-Estelle. In this paper, we describe a method for analysing the performance of a multimedia protocol specified in Time-Estelle. To aid the analysis, we introduce a traffic model called the Time-interval Performance Indices in order to capture the burstiness and time correlations of realistic multimedia traffic. Thus, performance parameters of multimedia systems, such as the long-term average rate and short-term peak rate allocation, and exploitation of statistical resources utilisation, can be analysed. To demonstrate the soundness of our method, we have applied it to the Resource ReSerVation Protocol and some results are included in this paper.