There is a great potential for using the discrete-time queues in the performance analyses of computer and communi- cation networks. The discrete-time queueing system has been found to be more appropriate in modeling computer and telecommunication systems than their continuous counterpart because the basic unit time in the discrete case is a binary code. Indeed, much of the usefulness of discrete-time queues derives from the fact that they can be used in the performance analysis of Digital Network and related computer communication technologies wherein the continuous-time models do not adapt.