Research On Virtual Network Survivability Technology Against Disaster Risks

The rapid development of the Internet makes our life more and more colorful,and the business needs are more and more diversified.However,the traditional network architecture cannot continue to meet the diversified business needs,and the fossilization phenomenon is increasingly serious.With the advent of network virtualization technology,the ossification phenomenon has been well resolved.By abstracting,isolating and allocating the physical network resources,network virtualization technology realizes that multiple virtual networks can share the resources of one or multiple physical networks without interference with each other.When a large-scale disaster decreases the reliability of underlying physical network equipments,the damage of the physical devices will cause a large number of virtual network business disruptions,which will cause a huge loss to the supplier.In this thesis,virtual machine migration technology is used to evacuate the virtual networks from the disaster area and survive these virtual networks.The main research work is as follows:The disaster risk caused by a large-scale disaster poses a serious threat to a large number of network components.Aiming at the survivability of virtual network business in the risk area,this thesis proposed a cooperation evacuation mechanism of multiple virtual machines.Based on the virtual machine online migration technology,according to the basic evacuation bandwidth and Dijkstra algorithm,the evacuation route is configured for the virtual machine,and the evacuation bandwidth is adjusted according to the evacuation completion time of the virtual machine,so as to realize the virtual machine collaboration evacuation of the same risk virtual network,make full use of the network resources,upgrade the evacuation bandwidth in the action state,reduce the average evacuation completion time of the risk virtual network and reduce the risk of damage to virtual network services.The simulation results show that the mechanism can achieve a smaller average evacuation completion time and a larger evacuation completion ratio.Under the disaster risk model,the physical devices are destroyed with a certain probability,and the physical links are more prone to be destroyed than the physical nodes.Once a physical link is destroyed,it mgiht cause a huge impact on the migration of virtual machines,which is not conducive to the virtual network evacuation from the disaster area.In order to solve the problem of virtual machine migration failure due to the disruption of the migration path during the online migration of risk virtual machine,this thesis propose a virtual machine migration path and bandwidth configuration scheme based on physical link reliability.In this scheme,the postcopy migration technology is employed.The maximum migration completion time of a virtual machine is limited by an initial migration bandwidth.The migration disruption ratio of a virtual machine is minimized by configuring the auxiliary path for the low reliability migration path.The resource utilization of the low reliability links is improved by preferentially upgrading the bandwidth of low reliability migration path,so as to reduce the number of impacted migrations due to the disruption of low reliability links.