Structural optimization in limited access trunk groups

The limited-access trunk group is a class of service system in which an arriving call can get service only from some subset of channels. Such systems arise in modelling certain telecommunication systems. We investigate systems where incoming calls which are denied service are lost. We establish light traffic theorems for Poisson traffic which show that dedicated systems are asymptotically preferable to other arrangements. However, for heavier blocking levels, a more uniform allocation of the available channels may be preferable. We also study how the crossover between these tendencies depends on the distributions involved.