Impairment-aware multicast tree design for hierarchical optical path networks

We propose a novel impairment-aware multicast tree design algorithm for hierarchical optical path networks. The proposed algorithm consists of grooming wavelength multicast trees tailored to service-specific distributions that are developed based on the inclusive relationship and a joint optimization of waveband trees. 3R regenerator placement subject to an optical transparent reach limit constraint is also considered. Numerical experiments show that the waveband multicast tree can significantly reduce the facility cost and that the proposed algorithm can reduce the necessary number of 3R regenerators.