The resource address of the information is generally given in the form of a domain name. How does the client know the IP address of the host?
The conversion from a domain name to an IP address is done by a domain name server (DNS) system. This system works in the client/server mode. The working process of DNS is similar to the telephone number service in the telephone system. In order to make a call, the caller must use the telephone number. If the caller does not know the other party's phone number but knows the other party's name, address and city name, then you can get the other party's phone number from the telephone number station. When an application requires a host domain name to be converted into an IP address, the application becomes a customer of the domain name system. The software that issues a domain name resolution service request on the client is called a resolver. The resolver is both the service provider of the user program and the user of the domain name server. It establishes a connection with the domain name server and transmits the host name to the domain name server. The host that provides the name resolution request service software on the server is called a domain name server. After searching, the domain name server sends the host's IP address back to the resolver.
There are two ways to resolve domain name servers: the first is called recursive resolution. The parser issues a recursive query request to the server. The server first searches within the jurisdiction. If it is found, the result will be returned to the parser side; otherwise, a request is issued to the root server, and the root server will proceed from top to bottom. The second type is called forwarding resolution. Each time the parser requests a name server. When a name server cannot provide an answer to a question, the server requesting this time returns the address of the next request server, and the parser sends a new request to another name server. Therefore, no matter which resolution method is used, each resolver knows at least how to access one name server and each name server knows at least the address of one other name server.
During this process, if the domain name entered by the user is incorrect or cannot be found, the parser will prompt an error message. The whole process seems quite cumbersome, but due to the use of a cache mechanism, all the host addresses recently found are stored in the cache, so the query process is very fast.
Of course, if you directly enter the IP address in the unified resource locator, such as "HTTP: //10.67.53.5", the network will eliminate the process of domain name conversion. Article entry: dnbm Editor: dnbm
The conversion from a domain name to an IP address is done by a domain name server (DNS) system. This system works in the client/server mode. The working process of DNS is similar to the telephone number service in the telephone system. In order to make a call, the caller must use the telephone number. If the caller does not know the other party's phone number but knows the other party's name, address and city name, then you can get the other party's phone number from the telephone number station. When an application requires a host domain name to be converted into an IP address, the application becomes a customer of the domain name system. The software that issues a domain name resolution service request on the client is called a resolver. The resolver is both the service provider of the user program and the user of the domain name server. It establishes a connection with the domain name server and transmits the host name to the domain name server. The host that provides the name resolution request service software on the server is called a domain name server. After searching, the domain name server sends the host's IP address back to the resolver.
There are two ways to resolve domain name servers: the first is called recursive resolution. The parser issues a recursive query request to the server. The server first searches within the jurisdiction. If it is found, the result will be returned to the parser side; otherwise, a request is issued to the root server, and the root server will proceed from top to bottom. The second type is called forwarding resolution. Each time the parser requests a name server. When a name server cannot provide an answer to a question, the server requesting this time returns the address of the next request server, and the parser sends a new request to another name server. Therefore, no matter which resolution method is used, each resolver knows at least how to access one name server and each name server knows at least the address of one other name server.
During this process, if the domain name entered by the user is incorrect or cannot be found, the parser will prompt an error message. The whole process seems quite cumbersome, but due to the use of a cache mechanism, all the host addresses recently found are stored in the cache, so the query process is very fast.
Of course, if you directly enter the IP address in the unified resource locator, such as "HTTP: //10.67.53.5", the network will eliminate the process of domain name conversion. Article entry: dnbm Editor: dnbm