Energy efficient anycast routing for scheduled lightpath demands in optical grids

Optical grids are attractive candidates to meet the large-scale computing, storage and data transmission capabilities in a number of emerging application areas. In many grid applications, it may be possible to select one out of a number of possible destinations to execute a specific job. This is known as anycasting, and in this paper we exploit the inherent flexibility of anycasting for energy efficient routing in optical grids. We propose an optimal integer linear program (ILP) formulation for selecting routes and destinations to minimize the total energy consumption of a set of scheduled lightpath demands. Our approach takes into consideration energy consumption at the network nodes and along the optical fibers, as well as the start time and duration of each scheduled demand. To the best of our knowledge, this is the first work to address the problem of energy-aware routing of scheduled demands in optical grids. Simulation results demonstrate that significant improvements in energy consumption can be achieved compared to both existing energy-aware unicast routing and holding-time-unaware approaches.