The OSI is an abstract model of how web link protocols and equipment should communicate and work together.
The OSI model is a technology standard maintained by theInternational Organization for Standardization (ISO).
Layers in the OSI model are ordered from the lowest layer to highest.

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Together, these layers comprise the OSI stack.
Generally speaking, software in these layers perform app-specific functions like data formatting,encryption, and connection management.
See these commonquestions and answers about the OSI modelfor more information.