The Simulation of Finite-Source Retrial Queueing Systems with Two-Way Communication and Impatient Customers.

The aim of the paper is to analyze a M/M/1//N finite-source, two-way communication retrial queueing system with an unreliable server and impatient customers. In this model, every request in the source is eligible to generate customers when the server does not function but they are forwarded immediately to the orbit. Customers may depart from the system during its waiting in the orbit after a random time and they get back to the source. All random variables involved in the model construction are supposed to be independent of each other. The novelty of the investigation is to carry out a sensitivity analysis comparing various distributions of failure time on the performance measures such as the mean number of customers in the orbit, the mean waiting time of an arbitrary customer, probability of abandonment, etc. With the help of self-developed simulation program, results are illustrated graphically.