IP addresses can be classified into a, B, C, D and e according to different network numbers and host numbers.
1. Class a IP address: a 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", and the address range is 1.0 0.0 to 126.0 0.0。 There are 126 class a networks available, and each network can accommodate more than 100 million hosts.
2. Class B IP address: a 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", and the address range is 128.0 0.0 to 191.255 255.255。 There are 16382 class B networks available, and each network can accommodate more than 60000 hosts.
3. Class C IP address: a 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". Range from 192.0 0.0 to 223.255 255.255。 Class C networks can reach more than 2.09 million, and each network can accommodate 254 hosts.
4. Class D address is used for multicast: the first byte of class D IP address starts with "lll0", which is a specially reserved address. It does not point to a specific network. At present, this type of address is used in multicast. Multicast address is used to address a group of computers at a time, which identifies a group of computers sharing the same protocol.
5. Class E IP address: starts with "llll0" and is reserved for future use. All zero ("0.0.0.0") addresses correspond to the current host. The IP address ("255.255.255.255") of all "1" is the broadcast address of the current subnet. (ipdezhidefenleiyounajichong)