OBSERVING QUEUES BEFORE JOINING

We consider a queueing system with two servers, each with its own queu e. The interarrival times are generally distributed. The service time for each server is exponentially distributed but the rates may be diff erent. No jockeying between the two queues is allowed. We consider sit uations in which a smart customer can delay joining a queue until some arrivals or service departures have been observed. All other customer s join the shortest queue. We find conditions under which the smart cu stomer can lower its expected sojourn time in the system by waiting an d observing rather than immediately joining the shortest queue.