As most of the static traffic grooming technology is

as reported in relevant literature

not applicable to large-scale optical networks

this paper presents an effective clustering-based static traffic grooming algorithm.When this method is applied

the network is decomposed into clusters of different hierarchical levels

and one node in every cluster is chosen as the head-node in charge of inter-and intra-traffic grooming.Simulation results show that this algorithm performs better than other known static traffic algorithms.