Research On Reliable Embedding Algorithm For 5G Network Slicing

Faced with the extremely diverse performance requirements of different scenarios,network slicing has become one of the main driving forces in the development of 5G network.Network slicing enables operators to create multiple logical networks on demand under the same physical infrastructures,so as to meet the differentiated traffic needs from all kinds of vertical industries.Due to the finiteness of available physical resources and the differences among devices in terms of performance,operators need a reliable and effective network slice embedding scheme to achieve resource optimization and to meet the reliability requirements of various services.This thesis mainly focuses on the issues of reliable network slice embedding and the main research contents and innovations of which are summarized as follows:1.To meet the diversified demands from different services while ensuring the reliability of each network slice through effective dynamic resource management,this thesis jointly considers computing resources,link resources as well as radio remote unit to investigate the dynamic,lightweight and reliable network slices embedding scheme.Firstly,a multi-objective resource optimization model oriented to reliability constraints is established with the introduction of Lyapunov stochastic optimization technique.Then,a queue stability based virtual node embedding algorithm and a reliability based virtual link embedding algorithm are proposed.Finally,a series of discrete time windows have been exploited to dynamically process network slice requests to realize online network slice embedding.Simulation results show that the proposed algorithm can improve resource utilization while guaranteeing the reliability of network slice.2.Traditional network slice embedding schemes usually have relatively low resource utilization,and also neglect differential reliability requirements of virtual network functions(VNFs),therefore resulting the poor reliability of network slices.In order to solve the situation,this thesis proposes a reliability-aware network slice reconfiguration and embedding strategy.At first,a reliability and available resources oriented utility function is constructed to evaluate the expenditure that operators spend to realize reliable network slice embedding.Then,both consideration of the resource requirements and the location constraints of VNF,a measurement to quantify the reliability requirement of VNF is proposed.Based on the above works,the reliable network slice embedding problem is formulated as an integer linear programming which maximizes the profits of reliable VNF deployment while minimizing the consumption of link bandwidth resource.Finally,a strategy consisting of two separate parts is proposed to solve the formulation.For network slices can meets its reliability requirements,a network slice reliable embedding algorithm based on neighborhood search is proposed to jointly optimize the computing and bandwidth resources.As for the network slices that fail to successfully embed because of VNFs' high reliability requirements,a network slice reconfiguration embedding algorithm based on key VNF backup is proposed to improve the reliability of network slice and to save the overhead of backup resource.Simulation results show that the proposed strategy can improve the resources utilization and reduce the embedding cost on the premise of guaranteeing VNFs' reliability.