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This article will explain in detail what is the service in internet that does not need to enter account and password. The editor thinks it is very practical, so I share it with you for reference. I hope you can get something after reading this article.

The service that does not need to enter account number and password in internet is a service of DNS;DNS. As a distributed database that maps domain name and IP address to each other, it makes it more convenient for people to access the Internet.

This article operating environment: windows7 system, Dell G3 computer.

What is the service in internet that does not need to enter an account number and password?

In Internet, the service that does not need to set accounts and passwords for users is the DNS-- domain name system.

Domain name system (Domain Name System, abbreviation: DNS) is a service of the Internet. As a distributed database that maps domain names and IP addresses to each other, it makes it more convenient for people to access the Internet. DNS uses UDP port 53. Currently, the limit for the length of each first-level domain name is 63 characters, and the total length of a domain name cannot exceed 253 characters.

Responsible for putting FQDN (that is, with "." The name at the end of the separation) is translated into an IP. The original DNS system used a huge hosts.txt file, but after a period of time, the developer had to use the database instead of the hosts.txt file, and finally developed to the current distributed database.

The DNS system is a huge tree with an unnamed root at the top and arpa,com,edu,gov,int,mil,us, cn at the bottom. Wait, wait. (this is the technical privilege).

But now it is almost universal; us, cn, etc., are called national domains. The domain names in this tree are not uniformly managed. The Network Information Center (NIS) is responsible for assigning top-level domains and delegating authorities to other designated areas.

There are two ways to map hostnames to IP addresses:

1) static mapping, host-to-IP address mapping is configured on each device, and each device maintains its own mapping table independently, and is only used by this device.

2) dynamic mapping to establish a domain name resolution system (DNS), which only configures host-to-IP address mapping on special DNS servers. Devices on the network that need to communicate with hostnames first need to query the corresponding IP address of hosts from the DNS server.

The process of getting the IP address corresponding to the host name through the host name is called domain name resolution (or host name resolution). When resolving domain names, we can first use the method of static domain name resolution, and then use the method of dynamic domain name resolution if the static domain name resolution is not successful. Some commonly used domain names can be put into the static domain name resolution table, which can greatly improve the efficiency of domain name resolution.

This is the end of the article on "which service does not need to enter account and password in internet". I hope the above content can be helpful to you, so that you can learn more knowledge. if you think the article is good, please share it for more people to see.

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