Multi-rate call congestion: fixed point models and trunk reservation

This document gives a brief survey of the state-of-the-art techniques in calculating the call congestion in a heterogenous traffic environment on a single link when Trunk Reservation (TR) is used to equalise the blockings. By means of exact and approximate techniques, it is shown that the blockings are sensitive to changes in mean holding time ratio. TR may not be a robust method when heterogeneous traffic is present. A fixed point model is derived to calculate the end-to-end blocking probabilities in an ATM network at the call level or in a multi-rate circuit-switched network