Survivable services oriented protection level-aware virtual network embedding

Abstract Network virtualization permits the creation of several logical networks (virtual networks) on one shared physical network referred as the substrate network. To protect a network against single substrate link failures, fast local reroute is preferred. With the reservation of backup resources, the flows are switched quickly from primary to backup paths upon substrate link failure to ensure service continuity. Due to the difficulty of primary and backup mappings, most of works in the literature separates the mapping of primary virtual network from the setting of backup paths. Although this approach optimizes primary resources, it can lead to inefficient protection since the existence of backup paths depends on the selected primary paths. In this paper, we propose a framework for protection-level-aware virtual network embedding which minimizes the risks of unrecoverable failures. With our propositions, the primary paths are selected among those which can be fully protected, if there is no such path, then we take the least vulnerable links in order to minimize the failure probability. For primary mapping, we propose a flexible on-line backup verification-based heuristic and a fast backup pre-verification-based heuristic. With the first heuristic, the backup path feasibility is verified on-line for each potential primary link, whereas we pre-compute for each substrate link the optimized set of backup tunnels all the backup paths in advance are deduced with the second heuristic. Simulations show that our propositions significantly reduce the substrate link failure impact on virtual networks, at the price of a slight decrease of the primary acceptance ratio.