You can interconnect with the Internet by complying with the IP protocol. IP addresses are unique and can be divided into 5 categories according to the nature of the user (Recommended learning: Web front-end video tutorial)
Determine the legality of the IP
1. The IP address is 4 3-digit strings separated by ".";
2, each 3-digit number Must be between 0~255 (inclusive), otherwise it is illegal;
The most common one is unavailable (also called illegal IP) It is 169.254.x.x
3. The IP address can also be divided into intranet and public network. The following are intranet addresses, and the others are public network addresses. The intranet IP is used in the LAN:
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