Global uniqueness, relative to INTERNET,IP as logical address

The difference between a network and a distributed cluster system: Each node is a single computer, not a functional device within a variety of computers.

IP: Has global uniqueness, as opposed to INTERNET,IP as a logical address.

Port: There can be 65,536 ports in a PC, and processes exchange data over ports. When connecting, you need to enter the IP and enter the port information.

The computer communicates the actual process communication between the hosts, and the process communication needs to be contacted on the port.

192.168.0.23:21

Protocol: A rule, standard, or convention established for data Exchange (communication) in a network.

The protocols of different layers are different.

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Global uniqueness, relative to INTERNET,IP as logical address