ANALYSIS OF A RETRIAL QUEUE WITH MULTIPLE VACATIONS AND STATE DEPENDENT ARRIVALS

This paper examines an M/G/1 retrial queueing system with multiple vacations and different arrival rates. Whenever the system is empty, the server immediately takes a vacation. At a vacation completion epoch, if the number of customers in the orbit is at least one the server remains in the system to activate service, otherwise the server avails multiple vacations until at least one customer is recorded in the orbit. The primary arrival rate is lambda(1) when the server in idle and the primary arrival rate is lambda(2) when the server is busy or on vacation (lambda(1) > lambda(2)). The steady state queue size distribution of number of customers in the retrial group, expected number of customers in the retrial group and expected number of customers in the system are obtained. Some special cases are also discussed. Numerical illustrations are also provided.