What is the range of Class A IP addresses?

The range of Class A IP addresses: 0.0.0.0 to 127.255.255.255.

The first byte of a Class A address is the network address, and the other 3 bytes are the host address. In addition, the highest bit of the first byte is fixed to 0.

It should be emphasized here that the numbers 0 and 127 are not used as the IP address of the host. The number 127 is reserved for the internal loopback function, and the number 0 indicates that the address is the local host and cannot be transmitted, but 0 and 127 do It belongs to Class A address, so there are only 126 Class A addresses at most.

Private addresses and reserved addresses in Class A addresses:

10.0.0.0 to 10.255.255.255 are private addresses (the so-called private addresses are not used on the Internet , and is used as an address in a local area network).

127.0.0.0 to 127.255.255.255 are reserved addresses and are used for loop testing.

0.0.0.0 to 0.255.255.255 are also reserved addresses and are used to represent all IP addresses.

The default subnet mask for Class A addresses is 255.0.0.0

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