The composition of an IP address

P address refers to the Internet Protocol Address (English: Internet Protocol Address, also translated as Internet Protocol Address), which is the abbreviation of IP Address. The IP address is a unified address format provided by the IP protocol. It assigns a logical address to each network and each host on the Internet to shield the differences in physical addresses.

The IP address adopts a hierarchical structure; it is composed of two parts: the network number (net ID) and the host number (host ID).

According to different value ranges, IP addresses can be divided into five categories; the first 5 digits in the IP address are used to identify the category of the IP address:

● Class A address The first digit is 0;

● The first two digits of Class B address are 10;

● The first three digits of Class C address are 110;

● Class D address The first four digits of the address are 1110; the first five digits of the Class E address are 11110.

In fact, most of the network bits and host bits are distinguished by the subnet mask. The subnet mask corresponds to the IP address one-to-one. The subnet mask of 1 is the network bit. Bit, 0 is the host bit.

For example: 192.168.1.2 mask 255.255.255.0. The network bit is 192.168.1 and the host bit is 2

For example: For example, 172.16.2.160/255.255.255.0: The [network number] of this IP address

is 172.16.2.0 and the host number is 0.0 .0.160

Subnet division

For example: 172.16.2.160/255.255.255.192 (IP address/mask)

1010 1100 0001 0000 0000 0010 1010 0000 (Binary)

1111 1111 1111 1111 1111 1111 1100 0000 (Subnet mask)

Description:

Only the one who knows Only by using the net mask and IP can you know the specific network segment and host number;

The same subnet mask may not necessarily be the same network segment IP. IPs in the same network segment must have the same subnet mask.

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