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Abstract-A unified framework for traffic control and bandwidth management in ATM networks is proposed. It bridges algorithms for real-time and data services. The central concept of this framework is adaptive connection admission. It employs an estimation of the aggregate equivalent bandwidth required by connections carried in each output port of the ATM switches. The estimation process takes into account both the traffic source declarations and the connection superposition process measurements in the switch output ports. This is done in an optimization framework based on a linear Kalman filter. To provide a required quality of service guarantee, bandwidth is reserved for possible estimation error. The algorithm is robust and copes very well with unpredicted changes in source parameters, thereby resulting in high bandwidth utilization while providing the required quality of service. The proposed approach can also take into account the influence of the source policing mechanism. The tradeoff between strict and relaxed source policing is discussed.

A state-dependent policy for call admission and routing in a multi-service circuit-switched network is synthesiced. To meet different requirements the objective function is defined as the mean value of reward from the network. Policy iteration is applied to find the optimal control. Assuming link independence the network reward process is decomposed into the set of link reward processes thereby significantly reducing complexity. The approach is implementable for large systems if certain approximations are used. A simulation study shows that the algorithm converges in two iterations, exhibits good traffic efficiency, and provides a flexible tool for performance allocation among services. The approach also constitutes a framework for studying, synthesizing and optimizing other call admission and routing strategies. In particular the results of sensitivity analysis are used t o compare the proposed decomposition approach with that developed by F.P.Kelly for optimiration of a load sharing policy in telephone networks.

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