A robust QoS routing algorithm for hierarchical networks

We propose a robust routing algorithm for PNNI-based hierarchical networks, which can provide quality of service guarantee to diverse service requirements. The routing algorithm is based on a PNNI complex node model. One of the key features of the proposed algorithm is the ability to take into account inaccurate network information due to topology aggregation in the PNNI hierarchical architecture. Methods for determining the parameters of the complex node are discussed, and then incorporated into a QoS routing algorithm of polynomial complexity. Numerical results show the feasibility and efficiency of our algorithm, and that for QoS aggregation, least square approximation is a better optimization objective than maximum deviation minimization