A virtual network embedding scheme with two-stage node mapping based on physical resource migration

Recently network virtualization is considered as a powerful way to overcome the current ossification of Internet, and is viewed as the keystone of the next-generation network architecture. In network virtualization, virtual network (VN) embedding problem, which assigns virtual nodes and links to physical network, plays an important role. Due to the scarcity of physical resource, efficient and effective VN embedding schemes are necessary. Researchers usually narrow down the problem space with certain restrictions to propose efficient solutions, or pay more attention to improve the performance of link mapping stage. Though resources on physical nodes are also scarce, the node mapping stage is neglected. In order to better utilize resources on physical nodes, we develop a novel scheme with two-stage node mapping. In our scheme, physical resource migration of nodes makes node mapping more efficiently, and leads to a more flexible and reliable network virtualization environment. The simulations shows that our scheme increases the acceptance ratio of VN requests, and enhances the average revenue of physical network.