PETRI NET BASED PERFORMANCE EVALUATION OF CLIENT-SERVER SYSTEMS

Abstract

The client-server architecture differs significantly from corporate computing paradigm of the past in an important way. In a client-server paradigm, applications are no longer physically contained in one computer system, as they were in both centralized and decentralized models. Instead, applications, databases and information processing resources are divided among many system in a seamless communication network that appears to the user as a single user machine. In this thesis, client-server systems in which a set of workstations access file server over a local area network are considered. The systems are modeled by a class of stochastic Petri nets. The mean response time, and the throughput are evaluated for a client-server system based on token ring network and a system based on CSMA/CD network. Our models are different form the prevalent performance models of token ring or CSMA/CD network systems because of the message interdependencies introduced by the client-server structure., An approximate analytic-numeric method and the simulation is used to solve the models.