Bandwidth allocation scheme in ATM networks based on virtual path for different quality of service (QoS) requirements

Bandwidth allocation is a very important issue in ATM networks, especially when there are random fluctuating demands for service and variations in the service rates. In order to make ATM reliable, ATM is designed to support not only a wide range of traffic classes with diverse flow characteristics but also to guarantee the different Quality of Service (QoS) requirement as well. The QoS may be measured in terms of cell loss probability and maximum cell delay. We consider the bandwidth allocation scheme of ATM networks based on virtual path (VP) concept. The bandwidth is allocated individually for supporting different traffic classes with different QoS requirements within a VP. By applying the Markov Modulated Deterministic Process method, the different models of VP combinations are proposed in order to compute the minimum capacity and buffer size required to satisfy the entire QoS requirements when multiple classes of on-off sources are multiplexed into VP. The combinations of static VP, called static bandwidth allocation scheme, are proposed to achieve the optimum total capacity and total buffer required for satisfying the individual QoS requirements. Further, by revising the existing algorithms and cell loss probability function, the different priority assignments of VP combination, called dynamic bandwidth allocation scheme, are also proposed to compute the minimum capacity and buffer size. The simulations of these schemes are carried out to evaluate their performance.