What do IP addresses represent from left to right?

The ip address represents the network address and host address from left to right. Class A IP address consists of 1-byte network address and 3-byte host address; Class B IP address consists of 2-byte network address and 2-byte host address; Class C IP address consists of 3-byte network address address and a 1-byte host address.

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

The IP address consists of two parts, one is the network address and the other is the host address.

1. Class A IP address consists of a 1-byte network address and a 3-byte host address. The highest bit of the network address must be "0".

2. Class B IP address consists of a 2-byte network address and a 2-byte host address. The highest bit of the network address must be "10".

3. The Class C IP address consists of a 3-byte network address and a 1-byte host address. The highest bit of the network address must be "110".

For example, in a network segment such as 192.168.0.0, the network number is 192.168.0.0 and the broadcast address is 192.168.0.255.

Therefore, in a LAN, the addresses that can be configured in the computer are two fewer (network number, broadcast address) than the addresses in the network segment. These addresses are called host addresses.

In the above example, only the host addresses 192.168.0.1 to 192.168.0.254 can be configured on the computer.

Extension information

IP address mask:

To identify the network part and the host part of the IP address , to be combined with the address mask (Address Mask), the mask is also 32 bits like the IP address, expressed in dotted decimal notation. The mask part corresponding to the network part of the IP address is all "1", and the mask part corresponding to the host part is all "0".

By default, if there is no subnet division, the subnet mask of Class A network is 255.0.0.0, the subnet mask of Class B network is 255.255.0.0, and the subnet mask of Class C network is 255.255.0.0. The mask is 255.255.255.0. With subnets, network addresses are used more efficiently.

With the subnet mask, the IP address is identified as follows:

Example: 192.168.1.1 255.255.255.0 or identified as 192.168.1.1/24 ("1" in the mask number)

Fixed IP and dynamic IP

Basically, these two things are the product of the massive growth of network companies. For example, if you apply for a business model from China Telecom ADSL dedicated line, then it will give a fixed entity IP, and this entity IP is called "fixed IP".

If you apply for time-based ADSL, because the IP may be used by dozens of people, the IP of this computer will not be fixed every time you restart the computer to access the Internet, so it is called It is "Dynamic IP" or "Floating IP".

Basically, these two are "entity IPs", but they have different names due to different methods used by network companies to assign them to users.

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