ANALYSIS OF BANDWIDTH ALLOCATION STRATEGIES WITH ACCESS RESTRICTIONS IN BROAD-BAND ISDN

Abstract

We study bandwidth allocation strategies with access restrictions for the integration of wide-band (WB) and narrowband (NB) traffics in a broadband integrated services digital network. Access restrictions are set on both traffics to meet the grade of service required for each type of traffic. The WB traffic is assumed nonqueuable, whereas the NB traffic may be queued. Also, as an improved strategy, we consider an access strategy which allows each type of traffic to use its bandwidth in the access-restricted region with the risk of being preempted by an arriving call for which the overflowed region is reserved. Under this strategy, the preempted NB calls are queued on the head of waiting room and preempted WB calls are also queued in another finite waiting room. The performances of these strategies are analyzed in terms of access delay for NB traffics and blocking probability for WB traffics by the matrix-geometric solution method. We show numerically that these strategies can easily be adapted to varying traffic loads by changing the restriction levels.