Domain Name System (DNS)

Domain Name System (DNS), which is composed of the parser and domain name servers. Domain name server is the preservation of all hosts in the network and the corresponding IP address of the domain name, and has converted to IP address of the domain name server functionality. Which must correspond to a domain IP address, IP address does not have a domain name. Domain name system similar to the hierarchical structure tree. Domain name server for the client / server mode, the server side, it is mainly in two forms: the main server and forwarding server. Mapped to the IP address of the domain name of the process is called "domain name resolution." In the Internet domain names and IP addresses on a one to one between (or many to one), the domain name though for people to remember, but the machine only to each other between the IP address of conversion between them as domain name resolution, domain name by special resolution required to complete the DNS server, DNS server is the domain name resolution. DNS name for the Internet and other TCP / IP network, through a user-friendly name to find the computer and services. When the user input in the application DNS name, DNS service can resolve this name and other related information, such as IP addresses. Because, when you enter the URL in the Internet, through systematic analysis of DNS to find the corresponding IP address, so as to access. In fact, the domain name is the final point to IP.
 In the IPV4 IP is composed of 32-bit binary number, this 32-bit binary number into 4 groups each of eight binary digits, these eight binary number into decimal number, that is, we see IP address, its scope in the 0 to 255. Because, 8 binary to decimal conversion is the maximum range of 0 to 255. Has now begun trial operation in the future will replace the IPv4, IPV6, will be a 128-bit binary number that IP address.
 As we all know, when we are online, they usually enter the URL, such as, in fact, this is a domain name, and our computer network can only be used between the computer IP address to identify each other. Again, we go to a WEB server, a WEB page is requested, we can enter the URL in the browser or the corresponding IP address, for example, we're going to Sina, we can enter the URL address bar of IE, can also be input IP address, but the IP address this way or that we remember it is very difficult to remember, so the name has to say, this makes us easy to remember domain name.
 DNS: Domain Name System Domain Name System domain name is separated by a dot composed of a string of words or abbreviations, each domain name corresponds to a unique IP address, the name of the method or the so called domain name management domain name system management system.
 Application of the DNS, the client can own a domain name for resolution, or additional sub-domain name. DNS client application, it is recommended to apply one of two customers.