A call admission control scheme in ATM networks

In an ATM (asynchronous transfer mode) network, call admission control decides whether or not to accept a new call, so as to ensure the service quality of both individual existing calls and of the new call itself. The measure of service quality used for the call admission control considered here is virtual cell loss probability, PV. PV may be formulated simply from the maximum and the average cell rates alone, and it provides a good estimate of cell loss probability without respect to the burst lengths. PV computational complexity increases rapidly with an increase either in the number of call types, K, or in the number of existing calls of individual call types; and for this reason, the author proposes a method for calculating a PV approximation on the upper side, with the aim of achieving real-time call admission control. Its complexity of computation is a linear order of K. Also proposed is a call admission algorithm which utilizes this approximation method and for which, in some cases, the computational complexity is independent of K