Research On SDN-based Routing Emulation Technology Supported By Cloud Platform

The current rapid development and wide application of Internet technology is a doubleedged sword,which has both advantages and disadvantages.While various new network technologies emerge in an endless stream(such as the satellite internet,space-ground integrated network,named data networking,etc.),the frequency of network security incidents is also rising,resulting in an increasingly severe network security situation.Since the Cyber Range can emulate and reproduce various elements in the real cyberspace by using virtualization technologies,as well as offer the test-bed for the later researches of network and security technology,which can satisfy the growing demands of network new technology evaluation and security defense technology evaluation,it has irreplaceable research significance.In detail,Cyber Range includes network emulation,user behavior emulation,security automation test,data acquisition,effect evaluation,etc.,among which network emulation technology with highscalability and high-performance is the foundation.To satisfy the demands of high scalability and high-performance network emulation,the network route,the core element of the network,is taken as the starting point to conduct out the research of routing emulation technology.The current routing emulation technology based on virtualization can realize the routing emulation with a certain ability,but it has disadvantages such as low throughput,large resource consumption,and limited emulation functions.Aiming at this problem,by applying SDN technology,it mainly focuses on the high-performance routing emulation architecture,and further studies the routing emulation technology with high scalability,performance,and multiple functions.Specifically,the main research of this paper includes the following four aspects:1)A high performance routing emulation architecture based on SDN is proposed.In order to settle the problems of low emulation throughput and high resource consumption in the current virtualization based routing emulation,combined with the technical advantages of SDN with high data forwarding performance and low resource overhead,a routing emulation architecture based on SDN supported by cloud platform,Crouter,is proposed.Crouter strives to break through the inherent bottleneck of layer-2 forwarding capability of SDN,realizes highperformance routing emulation supporting layer-3 forwarding,which improves the forwarding performance of emulation network by optimizing the data forwarding mechanism of cloud platform.In addition,Crouter has enriched the function of routing emulation by designing OSPF routing protocol emulation and QoS emulation model.The experimental results show that the CPU and memory consumption of Crouter is only 2% and 2.1% of that based on virtual routing emulation technology,in the multi hop scenario emulation and multi node concurrent scenario emulation,the emulation throughput of Crouter is 2.49 times and 4.49 times of that based on virtual routing emulation,respectively,and the emulation forwarding delay is only11.1% and 51% of that based on virtual routing emulation,respectively.In addition,the Crouter is capable of supporting high fidelity emulation of OSPF routing protocol and QoS function.2)Based on the research of 1),a high availability routing emulation technology on the basis of SDN controller cluster is proposed to improve the scalability of emulation scale and the availability of emulation network.Firstly,a controller cluster scheduling mechanism is designed,which breaks through the management bottleneck of a single controller by managing the emulation network concurrently with multiple controllers,and the scalability of emulation scale has been improved furtherly by the controller evaluation model and controller scheduling algorithm.Subsequently,a emulation network recovery mechanism is designed,which plays a pivotal role in actively redelivering the routing nodes managed by a controller to other controllers when a controller terminates abnormally,and restoring the running state of the emulation network to guarantee the high availability of the emulation network.The experimental results show that: compared with the emulation network management based on single controller in 1),the high availability routing emulation technology based on SDN controller cluster can realize the concurrent emulation network management of controller cluster,which has improved the scalability of routing emulation scale.Even when a controller fails,the emulation network can continue to operate normally with a high availability.3)A multi-functional routing emulation technology is proposed in the study on the basis of virtualization.In order to settle the problem of limited emulation function in current virtualization based routing emulation,a multi-functional routing emulation technology is proposed in the study on the basis of Virtualization supported by cloud platform.The technology realizes the emulation of static routing,RIP routing protocol,OSPF routing protocol and BGP routing protocol through Quagga routing software,and realizes the functional emulation of data filtering,traffic monitoring and address translation through Iptables component,in addition,the automatic configuration mechanism is designed to reduce repetitive configuration operations.The experimental results show that the multi-functional routing emulation technology on the basis of virtualization can easily build a emulation network with multiple routing protocols,data filtering,traffic monitoring and address translation functions through automatic configuration mechanism.4)Based on the research achivements in 1),2)and 3),a routing emulation system on the basis of cloud platform is designed and implemented accordingly.The integration of scalable emulation for large-scale edge network and resource exclusive emulation for backbone network is realized by combining high-performance with low resource overhead routing emulation technology based on SDN technology and multifunctional routing emulation technology based on virtualization technology.The system designs the modules of visual management,link performance emulation and topology automatic deployment,which is able to improve the usability of routing emulation,the fidelity of link emulation and the deployment performance of emulation topology.In addition,the function verification and application have been carried out for WAN emulation topology.