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This article is about what kind of special address 127.0.0.1 belongs to on the Internet. The editor thinks it is very practical, so share it with you as a reference and follow the editor to have a look.

127.0.0.1 belongs to the loopback address, which refers to the local machine, which is generally used for testing; the loopback address is the local loopback address, that is, the IP address inside the host IP stack, which is mainly used for network software testing and local inter-process communication. No matter what program, once the loopback address is used to send data, the protocol software immediately returns without any network transmission.

This article operating environment: Windows7 system, Dell G3 computer.

What kind of special address does 127.0.0.1 belong to?

127.0.0.1 is the loopback address, which refers to the local machine, which is generally used for testing. The loopback address (127.x.x.x) is the local loopback address (Loopback Address), that is, the IP address inside the host IP stack, which is mainly used for network software testing and local inter-process communication. No matter what program, once the loopback address is used to send data, the protocol software immediately returns without any network transmission.

Special address

The IP address consists of two parts, the network address and the host address. The network address indicates which network it belongs to, and the host address indicates which host it belongs to. The two are master-slave relationship. The four types of IP addresses identify a host in the network. The address length of IPv4 is 32 bits, a total of 4 bytes, but in practice we use dotted decimal notation.

According to the network number and host number, IP addresses are divided into three categories A, B, C and special addresses D and E. All zeros and all ones are reserved.

Class A: the first byte is the network number, and the last three bytes are the host number. The IP address of this class is preceded by "0", so the network number of the address is between 1 and 126. It is generally used in large networks.

Class B: the first two bytes are the network number and the last two bytes are the host number. The IP address of this class is preceded by "10", so the network number of the address is between 128 and 191. It is generally used in medium-sized networks.

Class C: the first three bytes are the network number and the last byte is the host number. The first IP address of this class is "110", so the network number of the address is between 192 and 223. It is generally used in small networks.

Class D: is a multicast address. The first IP address of this class is "1110", so the network number of the address is between 224 and 239. It is generally used for multicast users [1].

Class E: is a reserved address. The IP address of this class is preceded by "1111", so the network number of the address is between 240 and 255.

Return address: 127.0.0.1. It is generally used for testing. For example: ping 127.0.0.1 to test whether the native TCP/IP is normal.

In the regulation of classful IP address, the first part is that 1x126 is a class An address and 128x191 is a class B address, then the intermediate 127.0.0.1 is called the local loopback address, which has two main functions: one is to test the network configuration of the machine, and the ability to PING 127.0.0.1 indicates that there is no problem with the installation of the network card and IP protocol. Another function is that some SERVER/CLIENT applications need to call resources on the server when they are running, generally specifying the IP address of SERVER, but when the program is to run on the same machine and there is no other SERVER, it can install SERVER resources on the local machine, and the IP address of SERVER can also be set to 127.0.0.1.

Enter 127.0.0.1 in the ie browser

For most people who are used to using localhost, it essentially points to the local IP address 127.0.0.1. A configuration file in the operating system (the path in windows is C:\ WINDOWS\ system32\ drivers\ etc\ hosts,Unix/Linux path is / etc/hosts) binds localhost to 127.0.0.1.

127.0.0.1 is often used by website builders.

The "ping 127.0.0.1" command is commonly used to do a loop test on the local machine to verify that the local TCP/IP protocol suite is installed correctly. But did you find out? The same test results can be obtained by using the command "ping 127.1". In fact, the two commands "ping 127.1" and "ping 127.0.0.1" are the same, and they are both doing circuit testing.

Ping 127.0.0.1

What causes it? This is the skill of using IP address in the application of Ping command. As we all know, the IP address consists of 32-bit binary digits. In order to facilitate memory, every 8-bit binary number is converted into a decimal number, thus forming an easy-to-remember IP address composed of four-part decimal numbers (such as 127.0.0.1). Because the Windows operating system has the function of automatically populating ".0", I can change "127.0.0.1" to "127.1".

However, the omission of ".0" is conditional and cannot be omitted arbitrarily. In the application of the Ping command, one or more ".0" that appears before the last decimal number of the IP address can only be omitted, such as rewriting the "ping 127.0.0.1" command to "ping 127.1".

Thank you for reading! This is the end of the article on what kind of special address 127.0.0.1 belongs to on the Internet. I hope the above content can be of some help to you, so that you can learn more knowledge. If you think the article is good, you can share it for more people to see!

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