LAUSR

The study presented here deals with the steady state analysis of bulk arrival retrial queue with unreliable server and multi phase essential services. The server renders service to two types of customers viz. priority (type 1) and ordinary (type 2) customers. The ordinary customers are forced to join the orbit on nonavailability of the server whereas priority customers are served by the server as soon as they arrive. The service is provided in ‘ l’ essential phases for both type of customers. Moreover, the server is not an ideal server and hence may stop working in between. As soon as the server fails or stops working, it is sent for repair immediately. The broken down server is also repaired in ‘ d’ essential phases. In the present investigation, the supplementary variable technique and the method of generating function have been used. The sensitivity of various parameters on the system performance has been examined numerically by taking an illustration.