Finally, we comment on the amazing fact that the proof of Little’s law turns out to be independent of
• specific assumptions regarding the arrival distribution A(t)
• specific assumptions regarding the service time distribution B(t)
• number of servers
• particular queueing discipline
Little’s law is important for three reasons:
• because it is so widely applicable (it requires only very weak assumptions), it will be valuable to us in checking the consistency of measurement data
• for example, in studying computer systems we frequently will find that we know two of the quantities related by Little’s law (say, the average number of requests in a system and the throughput of that system) and desire to know the third (the average system residence time, in this case)
• it is central to the algorithms for evaluating several queueing network models