Traffic contract parameters and CAC guaranteeing cell-loss ratio in ATM networks

Connection Admission Control (CAC) is a key part of traffic control and still leaves several challenging problems peculiar to ATM networks. One of these problems is how to assign sufficient bandwidth for any cell arrival process that satisfies the source traffic descriptor values specified by negotiation between the network and a user at the connection setup. Because the source traffic descriptor cannot describe the actual source traffic characteristics completely, it has already been studied extensively that how to estimate sufficient bandwidth under the assumption that the actual traffic parameter values in the source traffic descriptor are equal to the negotiated values. This paper extends the studies in the literature to how to estimate sufficient bandwidth only assuming that the actual values satisfy the negotiated values, that is the actual values is less than or equal to the negotiated values. We show the sufficient condition for negotiated source traffic descriptors ensuring that the cell-loss ratio calculated from the negotiated values is always the upper-bound of the actual cell-loss ratio. Using this condition, we propose a CAC that can guarantee cell-loss ratio objective so far as a user satisfies the source traffic descriptor values.