A model for virtual tree bandwidth allocation in ATM networks

The technique of virtual paths is used in ATM networks to perform bandwidth allocation for virtual circuits and to simplify setting up of virtual circuits in response to connection requests. The author describe a new technique called virtual trees that can be used for bandwidth allocation in ATM networks. A virtual tree corresponds to pre-allocated bandwidth along a set of links in the network that form a tree rooted at a source node and leading to various destinations. The use of virtual trees provides more flexibility to a source node in setting up a virtual circuit and results in smaller rejection probabilities for connection requests. virtual trees retain all the advantages of virtual paths but have a better performance potential. The authors present an optimization model for bandwidth allocation for virtual tree configurations and present the results of a simulation study comparing the performance of virtual trees with that of virtual paths