ITU-T Recommendation G.694.1 defines normative DWDM frequency grids, each being a reference set of values that correspond to allowed nominal central frequencies, obtained using a fixed channel spacing (e.g., 12.5 GHz, 25 GHz, 50 GHz or 100 GHz). This rigid, grid-based approach does not seem well adapted for data rates beyond 100 Gb/s, is particularly inefficient when a whole wavelength is assigned to a lower rate optical path, and is not flexible enough for multi-rate systems . Consequently, the next generation of optical networks will require a flexible, highly efficient and adaptive management of the optical spectrum, along with advanced optical modulation schemes that efficiently use allocated spectrum slots, and recent progress on optical network technology justifies research on both new optical transmission systems as well as the applicability of control and management frameworks to such networks. We design and deploy a GMPLS control plane for flexible optical networks with coherent optical orthogonal frequency-division multiplexing (O-OFDM) transmission; we detail its functional architecture, which combines a centralized entity that performs path routing and modulation assignment, with a distributed spectrum allocation. The centralized entity (i.e., a path computation element) uses pre-configured static path characterizations, based on exhaustive OFDM transmission simulations, when performing dynamic path computation in line with GMPLS constrained shortest path mechanisms. The distributed spectrum allocation assigns frequency ranges (slots) to connection requests, by using dynamic signaling procedures and applying slot assignment policies. We summarize the control plane protocol extensions involved in the main functional aspects: routing and topology dissemination, path computation, signaling and resource reservation. We experimentally validate and evaluate the integrated centralized PCE and GMPLS control plane in a control plane testbed, obtaining key performance indicators such as path setup latency and blocking probability for different frequency slot assignment policies.

A testbed of OBS/GMPLS interworking network is established with the supporting of the BUPT-KDDI cooperation project. A dedicated GMPLS border controller with necessary GMPLS extensions and some OBS extensions are introduced in this network to achieve a dynamic, efficient and transparent inter-domain

As grid computing continues to gain popularity in the industry and research community, it also attracts more attention from the customer level. The large number of users and high frequency of job requests in the consumer market make this scenario a challenge for grid computing. Clearly, all the current client/server(C/S)-based architectures will become unfeasible for supporting large-scale grid applications due to their poor scalability and poor fault-tolerance. In order to address this issue, a novel C/S and peer-to-peer hybrid architecture to realise a highly scalable and flexible platform for optical grid is proposed here. The anycast algorithms, which are used to search suitable resources for job requests in this hybrid architecture, are also investigated in detail. Simulation and experimental results show that the proposed architecture is suitable and efficient for grid applications, and it outperforms C/S-based architecture in a large-scale grid environment.