What is DNS

DNS is also called domain name system, which is a hierarchical naming system built on a database; on the World Wide Web, dns maps IP and domain names to each other, and maps them into a distributed database, allowing users to access the Internet .

#The operating environment of this article: Windows 7 system, Dell G3 computer.

We often hear the term dns, but many people definitely don’t know what dns is. Let’s take a look at what dns means?

DNS is also called domain name system. It is a hierarchical naming system built on a database. On the World Wide Web, dns maps IP and domain names to each other and maps them into a distributed database, allowing users to access the Internet. .

The Domain Name System (DNS) includes a domain name tree. Each leaf is one or several resources. DNS is a domain. There may be many domains. Ultimately, they are managed by the administrator who is responsible for DNS. Parse and sort resources to address the user's needs. The DNS protocol runs on the UDP protocol, and when the request is larger than 512 bytes, the port number is 53.

We all know that an IP corresponds to a host name. A host name is composed of one or more strings. It is not easy to remember multiple characters. We only need to remember the DNS protocol. IP and There are two methods of host name mapping, dynamic mapping and static mapping.

#DNS resolution is the addressing method chosen by many people, and it is also an identity of the Internet. The development of domain names has enriched the resources of the Internet. Of course, if we set it up improperly, it will lead to hackers intruding and modifying the DNS information.

The above is a complete introduction to what DNS is. If you want to know more about HTTP video tutorial, please pay attention to the php Chinese website.

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