Research On Joint Allocation Of Application Resources And Optical Network Resources In Service Function Chain

Service Function Chain(SFC)is the most common end-to-end service model in current data center networks.In a resource-constrained environment,finding the optimal SFC resource allocation scheme is the key to building a low-cost,highly flexible data center network.Some good research results have been achieved on the issue of SFC resource allocation in traditional data center electrical switching networks.However,due to the narrow bandwidth,heavy energy consumption,and large transmission loss,the electrical switching is no longer applicable to the current data center network.In order to solve these problems,a data center network architecture based on a flexible elastic optical network is proposed and widely applied.The SFC optical spectrum resource allocation in the data center optical network is constrained by spectrum consistency,continuity and non-overlap,which makes the SFC resource allocation problem more complicated.This thesis mainly focuses on the SFC resource allocation problem in the data center optical network.The specific research results are as follows:In terms of SFC optical resource allocation,in order to effectively reduce the optical spectrum resource fragments and joint resource fragments generated during the SFC optical resource allocation process,an SFC optical spectrum resource allocation algorithm is proposed based on the auxiliary map.The algorithm effectively solves the joint spectrum resource by deploying the SFC service traffic preferentially on the fiber link between the non-data center node pairs by means of the auxiliary map,so as to prevent the situation where the application resources and optical resources are not equal in the data center nodes.In addition,the algorithm is designed with a variety of spectrum resource quantization strategies to calculate the path cost of the virtual network function link(VNFL)to determine the final VNFL mapping scheme.The simulation results show that the SFC optical spectrum resource allocation algorithm based on the auxiliary map reduces the spectrum resource fragments and joint resource fragments under the premise of ensuring the service delay,improves the utilization of optical network spectrum resources,and effectively reduces the service blocking rate.In terms of SFC application resources and optical resource joint allocation,this thesis combines the characteristics of SFC services.In order to maximize the global resource utilization,this thesis establishes an integer linear programming model(ILP)that considers the virtual network function(VNF)mapping constraint and routing spectrum allocation constraint to obtain the minimum mapping cost.The algorithm firstly solves the longest common VNF subsequence by dynamic programming to obtain the VNF mapping candidate scheme,and then calculates the VNF deployment cost based on the VNF aggregation mapping resource quantization model to determine the final VNF mapping scheme.Finally,the algorithm is simulated by combining the VNF aggregation mapping algorithm based on the longest common subsequence and the SFC optical spectrum resource allocation algorithm based on the auxiliary graph.The simulation results show that the SFC resource joint allocation scheme can approximate the optimal solution of ILP within the effective time complexity.Compared with other algorithms,it maximizes spectrum resource utilization,and reduces the SFC service blocking rate.