Letter to the Editor—A Note on “Statistical Equilibrium”

Abstract
In most expositions of steady-state queuing theory in which the system can be represented as a Markov process, the condition of “statistical equilibrium” is introduced into the mathematical model for the queue by assuming that the mean transition rate into any given state is equal to the mean transition rate out of that state. The authors have found a slightly different approach that offers deeper insight into the relation between the queue and its model, and sometimes a reduction in the amount of algebraic manipulation required to find the distribution of queue lengths.