Research On Virtual Network Embedding Strategy Based On Survivability

The rapid development of the Internet has spawned massive network applications,the number of network users has increased dramatically,the scale of the network has been expanding,and the traditional autonomous network based on TCP/IP has been unable to meet the needs of the times because of its complexity and difficulty.The reconstruction of the network architecture is imperative.Network virtualization can achieve multiple heterogeneous virtual networks(VN)deployment on a shared infrastructure provider(InP)network and establishment of the Internet's new architecture without changing the existing network architecture to solve the existing network "rigid" problem.Virtual network embedding is a new challenge to be solved in the process of network virtualization.The existing virtual network embedding algorithm focused on how to improve the utilization of the underlying physical resources and reduce the complexity of the algorithm and studied less on the survivability.However,the network failure is inevitable caused by equipment aging,maintenance,hardware and software errors or network attacks.Based on the survivability of the virtual network,this paper designs an efficient and reliable virtual network mapping algorithm,which takes the fault recovery rate into consideration besides fully considering the resource utilization rate.In this paper,two kinds of survivable virtual network embedding schemes are proposed.The first scheme adopts active protection mechanism which allocate redundant backup resources for each virtual network before a network fault occurs,and design the topology of redundant backups so that a ring structure of the topology is formed with strong robustness.In the end,the primary topology and backup topology is formed.The backup topology is embbed on a reserved quota for backup on each physical link using a multiplexing sharing strategy which achieves load balance.The second scheme uses a passive protection mechanism,which start the fault recovery mechanism after the failure occurs.In order to improve the speed of fault recovery,the fast routing strategy is used which establish the physical link backup route set in order to reduce the fault recovery delay due to the path selection.On the basis of the routing set,the virtual network mapping algorithm based on probability mapping is adopted.In the mapping phase,the virtual link is mapped to the virtual link with high survivability so as to improve the efficiency and reliability of the algorithm.The simulation results show that the two schemes can improve the recovery rate of network failure and reduce penalty of the Infrastructure Provider caused by the broken of the Service Level Agreement due to the failure of the network,and improve the long-term profit.