Traffic grooming in hybrid ring-star optical networks

The increasing demand for Internet network capacity requires optical traffic-grooming technology to reduce the complexity of the network. A network with optical cross connects is one potential architecture to achieve this goal. We show that an alternate architecture based on a hybrid ring- star topology and waveband grooming helps to reduce the network complexity by minimizing the number of nodes and the number of ports required in each node. We develop an analytical method for the design of hybrid ring- star topologies to reduce the capital cost of the overall optical network. We evaluate the performance of our method in terms of the number of network elements required for a national backbone network and demonstrate its savings in comparison to waveband grooming. (C) 2007 Optical Society of America.