Traffic grooming techniques are used to combine low-speed individual requests for connections onto high-speed lightpaths in an efficient manner. Design of survivable grooming capable networks is of critical importance. For such networks, protection may take place at the lightpath level or at the connection level. However, optimal formulations for implementing protection at either level are computationally intractable and can only be used for very small networks. We present an efficient integer linear program (ILP) formulation for the complete survivable traffic grooming problem, including topology design, traffic routing, and routing and wavelength assignment, using both dedicated and shared protection at the lightpath level. Unlike existing formulations, our ILP is able to generate optimal solutions for practical sized networks with hundreds of traffic requests.
© 2008 Optical Society of AmericaPDF Article