A distributed routing and wavelength assignment algorithm for real-time multicast in WDM networks

Routing and wavelength assignment for online real-time multicast connection setup is a difficult task due to the dynamic change of availabilities of wavelengths and the consideration of wavelength conversion delay in wavelength division multiplexing (WDM) networks. This paper presents a distributed routing and wavelength assignment scheme for the setup of real-time multicast connections. It integrates routing and wavelength assignment as a single process, which greatly reduces the connection setup time. The proposed routing method is based on the Prim’s minimum spanning tree (MST) algorithm and the K-restricted breadth-first search method, which can produce a subminimal cost tree under a given delay bound. The wavelength assignment uses the least-conversion and load balancing strategies. q 2002 Elsevier Science B.V. All rights reserved.