What is DNS and what does it do?

What is DNS and what does it do?

DNS is a service of the Internet. As a distributed database that maps domain names and IP addresses to each other, it allows people to access the Internet more conveniently. Its main function is to connect familiar The URL is "translated" into an IP address that the computer can understand.

DNS

Domain Name System (DNS) is a method of solving online machine naming on the Internet. system. Just like when visiting a friend, you first need to know how to get to someone else's house. When a host wants to access another host on the Internet, it must first know its address. The IP address in TCP/IP is composed of four numbers separated by "." The composition is always not as convenient to remember as the name, so the domain name system is used to manage the correspondence between names and IPs.

Although nodes on the Internet can be uniquely identified by IP addresses and can be accessed through IP addresses, even if the 32-bit binary IP address is written as four ten-digit numbers from 0 to 255, Still too long and too difficult to remember. Therefore, people invented the domain name (Domian Name), which can associate an IP address with a group of meaningful characters. When a user visits a website, he or she can enter either the IP address of the website or its domain name. The two are equivalent for access. For example: the IP address of Microsoft's Web server is 207.46.230.229, and its corresponding domain name is www.microsoft.com. Regardless of whether the user enters 207.46.230.229 or www.microsoft.com in the browser, the user can access its Web website.

A company's Web website can be regarded as its online portal, and the domain name is equivalent to its house address. Usually the domain name uses the name or abbreviation of the company. For example, the domain name of Microsoft mentioned above is similar to: IBM's domain name is www.ibm.com, Oracle's domain name is www.oracle.com, Cisco's domain name is www.cisco.com, etc. When people want to visit a company's Web site and don't know its exact domain name, they will always enter the company name first as a test. However, a domain name consisting of a company's name or abbreviation may also be registered by other companies or individuals. There are even some companies or individuals that maliciously register a large number of domain names composed of the names of well-known companies, and then resell them to these companies at high prices to make profits. There are already some arbitration measures for domain name registration disputes, but to control this phenomenon from the source, a complete set of restriction mechanisms is needed, which is not yet available. Therefore, registering a domain name consisting of your own name as early as possible should be something that any company or institution, especially those well-known companies, must pay attention to. Some companies have already made protective registrations for domain names consisting of their own famous brands.

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