Research On The Resource Orchestration And Fault Management In Network Slicing For 5G

To embrace the future of 2020,mobile communication operators will step into the era of fifth generation mobile communication network(5G),5G will significantly lower the capital expenditure(CAPEX)and operating expenditure(OPEX)of network infrastructure.Moreover,the service demand of 5G and new technology represented by SDN/NFV and network slice will certainly motivate the innovation of network architecture.Network slice can gain superiority in many aspects of 5G mobile communication network,such as the flexible configuration resource sharing and support of vertical application,which all entail an efficient policy of resource orchestration and fault management.The In this paper,a research on 5G mobile communication network virtualization resource management and fault management is mainly illustrated in the following three aspects:(1)How to create a fine-granularity network slice according to the service demand.The diversity of mobile network service and difference between the requests of network traffic require that network could allocate the physical resources in a flexible and elastic way to initiate the slice according to the need of tenants.(2)How to locate the breakdown of network resources in network slice.Accurate fault allocation is the prime of slice management.In the model of network virtualization,the functions of network element are initiated via software.The abstraction of substrate network,dynamic changes of construction and frequent fault caused by similar operation bring more trouble to the problem of fault location.(3)how to recover and rebuilt the broken network function.The breakdown of network function may give rise to the interruption and loss of relevant subscriber data,which will affect the experience of users and service quality of termination significantly.To satisfy the high demand of reliability in 5G,certain policy must be implement to recover the broken network function.To solve the problems described above,this research based on a national high technology research and development program(863 program)"5G wireless network virtualization key technology research and validation" project.For 5G and the future evolution of mobile communication network architecture,we pay attention to the mobile communication network slice technology.Life cycle management of network slice,which includes resource arrangement and fault management issues,is the vital part of realizing the automatic network slice operations.In the process,main contributions are as follows:1.In virtual Evolved Packet Core(vEPC),service deployment is based on Service Function Chain(SFC).On account of traffic differentiation of mobile network,the proposed algorithm applies a modified virtual network embedding strategy in accordance with sub-graph isomorphism,which embeds the hierarchical service function chains coordinately to strengthen capacity of resources dynamic scheduling and Orchestration.The proposed heuristic algorithm collaboratively maps decoupling SFC with backtracking strategy.Firstly,candidate substrate subnet is preliminary selected on the basis of global resources capacity.Secondly,pruning condition is formulated based on the graph characteristics.Then,collaborative search strategy is designed according to the characters of vEPC mapping.Finally,the optimal scheme is selected via comparing cost indexes.The simulation results validate the effectiveness in request accepting rate and long-term revenue-to-cost rate.2.A virtual network fault location scheme based on Bayesian network is promoted.In virtualization environment,MANO is difficult to obtain a complete failure data.Network resources and components in virtual network are abstracted and layered,using EM algorithm to deal with incomplete network testing data and locating the failure through propagation mechanism and naive Bayesian analysis.According to the characteristic of virtualization environment,fault dependency graph was proposed to characterize fault propagation between network components.In the process of fault locating,the heath service information is considered as auxiliary knowledge to effective adapt the failure conditions in practical communication networks.3.A virtual network functional recovery strategy is proposed based on multi-dimension bin packing problem.In virtualization environment the underlying physical network recovery is more difficult owing to resource reuse.A number of VNFs runs on a shared physical device,so all VNFs will break down if the physical node crash.So a function failure recovery strategy in virtual network based on multi-dimension resource aggregation is put forward.VNF fault recovery problem is classified into bin packing problem and integer linear programming and genetic algorithm are utilized to process optimization calculation.