Design Of Algorithm For Construction And Deployment Of Service Function Chain In Network Slice

Due to the explosive growth of data traffic,the growing maturity of new technologies such as intelligent factory and Internet of vehicles,which require diversified network services,as well as the need for 5G network to provide customized network services for users by using network slicing technology,the traditional TCP/IP architecture network is facing great challenges.The integration of SDN and NFV technology can effectively solve the above problems and flexibly deploy network functions at the optimal location.The required VNF can be constructed into an ordered service function chain(SFC)according to the user's service needs,and then the SFC can be mapped to the slice network to realize customized network services for users.Service function chain construction is the basis of customizing network for users on slice network.In this article,a network slicing service function chain construction algorithm(DFC-SFCCON)based on depth-first search is designed.It can construct service function chain for multiple user requests simultaneously by using virtual network function dependency graph on slicing network.DFC-SFCCON algorithm is to transform the virtual network function dependency graph into a tree structure.In the building services chain for each user,first look for the virtual network function according to user's requirements on the tree structure level of the highest node,and then find the node's parent,grandfather node until the root node,and as the initial build plan,and then in turn construction scheme for the initial node to find brother extension construction scheme,the resulting SFC build solution set.The simulation results show that the proposed algorithm not only improves the construction speed of the service function chain,but also is not easily affected by the sequence between VNFs in the service request.This article also studies the deployment of service function chain in the core network slice.For the virtual machine resources have been allocated but network functions have not been deployed to the virtual machine,the deployment of service function chain is divided into two sub-problems: network function deployment and link mapping on virtual machine,and the SFC deployment algorithm based on genetic algorithm(GA-MCMF)is designed to minimize the overall service delay of the core network slice.Simulation results show that the proposed deployment scheme of service function chain has lower total service delay.Resources allocated for the virtual machine and the deployment of the network function,the function of the new service chain mapping DI-MCMF algorithm,this algorithm divide problems into VNF mapping and virtual link physical link two subproblems,first of all find out respectively VNF matching virtual machine,by the dynamic programming is to not circulation low latency algorithm to obtain VNF mapping scheme;Then,the minimum cost and maximum flow algorithm is used to obtain the virtual link mapping scheme.The computer simulation experiments show that the DI-MCMF algorithm can map the new service function chain to the slice network faster,and can not affect the normal operation of the original service function chain.