The Virtual Network Mapping Algorithm For Network Virtualization

With the rapid development of the Internet, the new Internet applications appear in the existing Internet infrastructure is difficult to be met, the existing network services architecture presents a certain extent ossified. And network virtualization technology is considered to be a rigid solution for network problems, which allows multiple isolated virtual networks that with different topologies coexist on these public infrastructures, to provide users with customized and different services. Meanwhile, the network virtualization technology by abstracting the underlying common physical facilities for network service providers to provide end to end customized services, and allows researchers to deploy new network protocols, network virtual ization technology has accelerated the development of new technologies and network protocols and deployment schedule, and promote future development and evolution of the network.However, in network virtualization, virtual network mapping is a great challenge for resource allocation. It needs to satisfy the constraints on the virtual network to mapping on the underlying physical facilities. In this problem, a virtual network is a common network topology consisting of a collection of nodes and links which connecting the nodes, in order to complete the virtual network mapping, each virtual nodes need to be deployed on the different physical nodes and each virtual links need to be mapped on the physical path corresponding to the physical nodes. At present, the research results of the problem are based on heuristic method. By the relation of the nodes and links mapping, these algorithms can be divided into two ways:the node mapping first two-stage mapping algorithm and node mapping and link mapping are coordinated mapping algorithm. In the two stages algorithm since the node mapping stage may make the virtual nodes too scattered on the physical nodes, which can lead to failure in the link map stage or because the physical path length is too large the consumption of link resources may be excessive, and ultimately reduce the virtual network mapping acceptance rate. In the two stage coordination algorithm, node mapping and link mapping process at the same time, the problem can be simplified equivalent to linear programming problem, however the time complexity of the algorithm is high, and the ability to reduce the consumption of physical resources is limited.Therefore, the current algorithms on the consumption of the underlying physical resources need to be reduced, and the algorithm running time can be shortened, evaluation factors also need to be improved, and the acceptance rate of virtual networks has great space for improvement. To solve the problem of virtual network mapping, and overcome the shortcomings of the existing algorithms, the paper has put a link-first based quick coordinated virtual network embedding algorithm and random virtual network embedding algorithm based on maximum independent link set. The corresponding algorithm simulations compared with the existing algorithms and analysis found that the two algorithms proposed save cost in the link mapping stage and improve the virtual network acceptance rate and physical network revenues, the algorithm is also effective to shorten the running time while the second algorithm due to its use of random principle when choosing a physical path to mapping, it can guarantee a certain degree of physical network load balancing.