Call and Burst Blocking in Multi-Service Braodband Systems with CBR and VBR Input Traffic

We consider a multi-service broadband system in which the services form diierent traac classes. The superimposed traac is carried by a link of xed bit-rate. The services are of constant bit-rate (CBR) as well as of variable bit-rate (VBR). The VBR services are characterized as ON/OFF sources. We derive approximate algorithms for the computation of blocking probabilities at call and at burst level. The algorithms consist of two phases using a product-form solution. The computational complexity of the approximations is low and allows the investigation of large numbers of traac classes. Comparison of numerical results with simulation results and results from an exact iterative algorithm indicate that the approximation is of excellent accuracy. It can be concluded from numerical results that the burst blocking probability is strongly dependent on the estimation of the required bit-rate of the VBR calls.