A general retrial system with additional vacation

This paper studies a retrial system with batch arrival and general retrial time, where the server may take an additional vacation after the essential vacation. In this system, primary customers arrive according to Poisson processes and receive corresponding service immediately if the server is available upon arrival. When the server is busy or on vacation, arriving customers enter a retrial orbit. If the orbit is empty, the server immediately leaves for the essential vacation. At the end of essential vacation, he may take one additional vacation. It is assumed that the retrial time and service time are all arbitrary distributed. This retrial system has potential applications in the packet‐switched networks and the proxy of WWW server. By applying the supplementary variable technique, some important performance measures are derived, which may be useful for network system designers and software system engineers.