The primary emphasis of this thesis is to evaluate in comparative terms the performance of three types of service disciplines in a Token Ring Local Area Network. The service disciplines studied are exhaustive, gated and limited service. These service disciplines play an important role in the network performance, especially when some users are relatively less active than others in contributing traffic load to the network. Network performance for these service disciplines are compared to determine which one of them gives better performance. Simulation is used for this study and results are presented in terms of average delay, queue lengths and delay histograms versus traffic intensity.