Consider that two identical M/M/1 queueing systems with the same rates and , which are in operation side by side (with separa in a premises.

Consider that two identical M/M/1 queueing systems with the same rates λ and μ, which are in operation side by side (with separa in a premises. The distribution of the total number of customers, N, in the two systems taken together in long-run is given by