To cope with the complexity of the ever changing internet architecture, network virtualization services are vowed to play an important role in the future. To provide such solutions effectively, internet providers face the problem of optimizing the allocation of virtual networks on their physical resources. Since this problem is known to be NP-hard, heuristic based online solutions tend to provide better response time, however they lead to non-optimal solutions. This paper shows how a periodic live migration of virtual networks, using a state provided by offline optimization, can help an internet provider increase its virtual network load by up to 20%. Due to better packing of virtual load, some physical resources can also be shut down to save energy
