Reference link https://en.wikipedia.org/wiki/OSI_model
APSTNDP: All People Seem To Need Data Processing.
Open Systems Interconnection Model.
Represents the bit-level transmission between network nodes over the connection medium.
Data: Bits across the wire (1s and 0s) as pulse of electricity or light.
Data Link Layer handles communications between adjacents network nodes via physical addressing (MAC).
Handles routing messages (packets) via the best route to reach its destination based on IP address.
Defines how data will be sent providing validation and security.
Layers 5-7 are typically managed by the application itself, providing the interface for the user to communicate.