An Analysis of Multi-Service Systems with Trunk Reservation Mechanisms

In this paper we consider a broadband system carrying diierent types of services. The transmission system is built by a set of links having a xed or quasi-stationary bandwidth, e.g. in the form of virtual paths arising in Asynchronous Transfer Mode networks. The bandwidth usage by diierent services of various bit-rates is organized in a complete sharing mode. We devote attention to two diierent call admission schemes: i) regular complete sharing and ii) complete sharing in conjunction with a trunk reservation mechanism. An overview on analytical methods dealing with models of both call admission schemes is given. An approximate recursive algorithm for trunk reservation which gives us the ability to deal with a large number of diierent traac classes is described. Considering a numberof services with diierent grade of service in term of blocking probabilities , a general rule is formulated to equalize the call blocking probabilities of any s e t of arbitrary service classes. Simulation results are presented to show the accuracy of the approximation. Some numerical examples are also carried out to illustrate the eeciency and the grade of service management capability of trunk reservation mechanisms.