Abstract
The multicast tree construction problem (MTCP) with wavelength reuse and migration on wide-area optical routing networks is investigated. Multicasting, if improperly implemented, can be bandwidth abusive due to the limited number of available wavelengths and the wavelength continuity constraint. Employing spatial reuse of wavelengths provides a high aggregate system capacity thereby increasing the amount of concurrency in the network. Besides, to accommodate new join calls, the wavelength of certain existing multicast connections could be migrated so that the blocking probability can be further reduced. Given a set of established multicast trees and a set of new join requests, the MTCP is to allocate a wavelength for each constructed multicast tree so that the number of wavelengths used is minimized. It is clear that MTCP is NP-complete and we propose an efficient distributed multicast tree construction heuristic for wide-area optical routing networks