(Every host on the Internet will have a unique IP address. But with the exhaustion of IPv4 addresses, the issue of IP addresses has become a hot topic again. This technical manual provides a detailed introduction to the basics of what IP is, the structure and classification of IP addresses, and the difference between IP addresses and machine addresses, as well as how to divide subnets and quickly calculate subnet masks, and how to manage DHCP scopes to prevent wireless Common techniques such as network IP address conflict, how to find the lost IP address of the access point, and how to obtain other people's IP address information.)