On the security protection of domain name server in Hefei Anchuan network
What is a domain name server? Anchuan network, a website company in Hefei, points out that the domain name service system (hereinafter referred to as DNS) is an indispensable service in all kinds of network services. The domain name server converts the hard to remember IP address into the domain name that is convenient to remember. If the domain name server responsible for domain name conversion is attacked and tampered with by abnormal information, the false DNS information generated will seriously affect the Internet users' inability to use the Internet, so that the website users want to visit is attacked, and the internal information of the website is maliciously tampered with. Therefore, Anchuan network, a website company in Hefei, believes that it is important to ensure the safe operation of the DNS server An important factor affecting the safe operation of the network.
On the operation principle of domain name service system
Anchuan network, a website company in Hefei, pointed out that the database system of DNS is a distributed database system with a hierarchical structure. DNS does not store the information of all hosts, but is stored in a large number of distributed domain name servers. These distributed domain name servers form a hierarchical database system, which is at the top level A root domain is represented by the symbol dot "." and can be further divided into hundreds of top-level domains, and each top-level domain is divided into sub domains. Generally, the sub domains of each parent domain are sub domains. Each domain has its own group of domain name servers. The host information of the current domain and the domain name server information of the child domains are saved in these domain name servers.
According to the work flow of DNS server introduced by Anchuan network, a website company in Hefei, the user machine requests domain name resolution and sends it to the local domain name server. When the local domain name server receives the domain name resolution request from the user, it will first query the local cache. If there is a record item, the local domain name server will directly Then return the results of the query; if there is no such record in the local cache, the local domain name server will send the domain name resolution request made by the user to the root domain name server, and then the root domain name server will return the address of the primary domain name server of the queried domain to the local domain name server; the local domain name server will send the request to the domain name service returned in the previous step The server that receives the request queries its own cache. If there is no such record, it will return the address of the related subordinate domain name server and repeat the above steps for many times until the record item is found. The local domain name server will return the query result to the user machine and save the record item in the local cache.
DNS has completed the transformation from centralized to distributed. When the DNS system was established, there were only hundreds of Web sites, and DNS gradually developed into a hierarchical distributed system. With the rapid development of WWW, the web search engine has encountered the problems of DNS technology. Now there are a large number of web pages distributed on many servers, but the current search engine repeatedly visits, downloads all web pages to a database system, and the data update rate and coverage rate There is no guarantee. It is obvious that the centralized framework can not adapt to the distributed WWW information management, that is to say, the key problem encountered by the current search engine is caused by the inappropriate basic structure of the system.
According to the analysis of the history of DNS technology development, the Anchuan network of Hefei website thinks that if web search engine can imitate DNS system to use hierarchical distributed framework structure, it will solve the key problem.
Key words: Hefei Network Company Hefei website construction Hefei Anchuan network actcms