Design And Implementation Of Deploying DNS System Based On The Anycast Technology

With the continuous development of the global Internet, especially the rapid development and popularity of the domestic Internet, netizen’s scale is more and more huge, the Internet has become an integral part of the majority of Internet users living. As the most basic network service of the Internet, because of its own service characteristics, Domain Name Service made more and more DNS system which initially used four-layer switching technology architecture appearing problems. The growing number of Internet security incidents prove that the bottlenecks of the four-layer switches in new connections decided that it is not suitable for application in large-scale DNS service.Based on the network status of Shandong Tietong DNS system, this text deeply analyzes the problems of the current network structure and security risks, puts forward to deploy DNS system based on the anycast technology, resolves the performance bottlenecks of Shandong Tietong DNS system with four-layer switching technology before the transformation, also eliminates the single point of failure hidden in the original network architecture.Anycast DNS is a kind of network technology which use anycast routing and switching technology to build a load-balancing domain name system. By routing announcement, the DNS address is broadcasted to the layer3switches or routers which all domain name servers directly connected. Dynamic layer3routing which guide on the access of the anycast DNS ip address achieves the load balancing of DNS query. When a server in the anycast DNS node has failed, its route can be stopped automatically by the customized health check mechanism to achieve the load taken over by the other internal server. On the basis of the transformation of Shandong Tietong DNS system as a background, this text detailedly discusses the present situation and problems of the existing four-layer switching technology to build a load balancing DNS system. Based on the deep analysis of the purpose and significance of improving the DNS system network architecture, this text reserches anycast technology principle and characteristics in detail, and it puts forward a plan to set up anycast DNS system based on the OSPF dynamic routing protocol with the single node centralized architecture, and it describes the specific implementation method. Moreover, it still provided a optimization scheme of improving anycast DNS design. This scheme improves the stability of the system and speeds up the recovery time in the failure of the system. Finally it introduces the overall design of the transformation, and it also analyzes the economic feasibility,by comparing the data of the system before and after the transformation, it analyzes and demonstrates the effect of performance optimization.After the transformation of the Shandong Tietong DNS system, the investment costs were greatly reduced than using layer-four switching equipment, a lot of money was saved for the company. At the same time, the way of system net organization was more reasonable, the credibility and safety of the whole system was strengthened. A good foundation was laid for the flexible and smooth expansion in the future. This text has certain practical value on optimizing the DNS system of the provincial operators with the single node centralized architecture.