The Point-To-Multipoint RWA Algorithm In All Optical Networks And The Simulation Implementation

Since the optical signal is switched and routed entirely within optical layer, all-optical networks promise to offer advanced transparency and enhanced flexibility compared with existing opaque optical networks. Therefore, all-optical networks are expected to be gradually deployed for the future optical networks. Moreover, with the increasing demands from various new bandwidth-hungry applications such as HDTV, it becomes an important and challenging topic to provide multicast services in all-optical networks.Due to the fact that the optical splitters and wavelength convertors are only sparsely deployed, all-optical networks are subject to the particular wavelength continuity and transmission impairment constraints. In response, a novel multicast-capable routing and wavelength assignment (MC-RWA) algorithm is proposed for the light-tree provisioning in all-optical networks. Compared with the existing algorithms, the proposed algorithm adds the destination nodes into the light-tree one by one and each newly added node should guarantee the maximum number of remaining wavelengths and the least number of hops. Furthermore, to enhance the flexibility of this algorithm, a light-forest instead of a single light-tree is preferred when the available wavelength in the network is limited.In order to evaluate the the performance of the proposed MC-RWA algorithm, a corresponding network simulation platform is newly developed based on OPNET. An enhanced signaling mechanism with entensions to RFC4875 is also built into this platform to dynamically provision the light-tree service. Through the simulation, it was found that the proposed MC-RWA can achieve the improved performance in term of the light-tree blocking probability.In conclusion, the MC-RWA algorithm in support of all-optical networking and the implementation of the simulation platform are reviewed and some constructive remarks are presented for the potential improvements.