Enhanced Blocking Probability Evaluation Method for Circuit-Switched Trunk Reservation Networks

We consider the problem of estimating steady-state blocking probability for circuit-switched networks that allow alternate routing with particular emphasis on networks protected by trunk reservation. We use a recently proposed blocking probability estimate, the Overflow Priority Classification Approximation (OPCA) as an alternative to the currently used Erlang's Fixed-Point Approximation (EFPA). We demonstrate empirically that OPCA provides a better blocking estimate than EFPA for circuit-switched networks with alternate routing, that are reasonably protected by trunk reservation.