A spanning tree-based QoS aggregation algorithm in hierarchical ASON

This letter proposes a new way of minimizing QoS parameters distortion caused by spanning tree topology aggregation in hierarchical automatic switched optical networks. It encodes the divide point information of the missing logical links in the spanning tree with a single float number. Based on this new method, an approximation algorithm is presented. Simulation results show that the proposed method and algorithm perform much better than the traditional way of decoding the spanning tree with upper or lower bounds.