OSI purpose:
Support the interconnection of heterogeneous networks
The application layer, presentation layer, and session layer are responsible for data processing. The
network layer, data link layer, and physical layer are responsible for data communication. The
transmission layer is end-to-end, that is, the logical interconnection between two network devices, regardless of how much there is in between The physical device of the
physical layer is a point-to-point work, that is, two network devices are directly connected
Transmission process:
