In the same network, the IP addresses of network addresses must be the same. Communication between computers can only be conducted between IP addresses with the same network address. If you want to communicate with computers in other network segments, you must forward them through the router.

Routers are divided into local routers and remote routers. Local routers are used to connect network transmission media, such as optical fiber, coaxial cable and twisted pair. Remote router is used to connect remote transmission media, and it needs corresponding equipment, such as telephone line with modem, wireless through wireless receiver and transmitter.

Principle:

Devices in the network communicate with each other mainly through their IP addresses, and routers can only forward data according to specific IP addresses. An IP address consists of a network address and a host address. In the Internet, subnet masks are used to determine network addresses and host addresses. Like IP addresses, the subnet mask is 32 bits.

And the two are in one-to-one correspondence. "1" in the subnet mask corresponds to the network address in the IP address, and "0" corresponds to the host address, so the network address and the host address constitute a complete IP address.