A Distributed Routing and Wavelength Assignment Algorithm for Real-Time Multicast in WDM All-Optical Networks

Routing and wavelength assignment for online real time multicast connection setup is difficult due to the dynamic change of availabilities of wavelengths on links and the consideration of wavelength conversion delay in WDM networks Assuming that each link has multiple fibres, there are wavelength converters only at part of nodes and the conversion delay is not negligible A distributed routing and wavelength assignment algorithm for the setup of real time multicast connections is presented based on the above assumption The algorithm is based on Prim’s MST （minimum spanning tree） algorithm It generates a sub minimal cost tree under a given delay bound first If there are nodes not included in the cost tree, a delay tree is generated to include the rest nodes The two trees are merged together The wavelength assignment uses least conversion and load balancing strategies