A mixed integer programming framework for virtual topology design in real-time optical networks

The proposed research investigates delay based virtual topology design using mixed integer linear programming which can be applied to present internet backbone network. In the first stage an arbitrary network is choosen with different distances between the nodes and different link capacities. A traffic matrix is applied and the corresponding virtual topology solved by convex optimization using mixed integer linear programming formulations that include lightpath routing, wavelength assignment, wavelength continuity, flow routing and traffic losses. In the second stage the network choosen for simulation is taken from the present SprintLink network, which is a global tier 1 network of Sprint Telecommunications used for providing internet to customers. MATLAB is used to solve the formulations using a special toolbox called 'MATPLANWDM' designed specifically for network planning in WDM networks. The advantage of using this toolbox is that it provides with the flexibility to implement user defined algorithm for network planning. The proposed method has improved the overall networks performance with least possible load.