TCP/IP model

This model was developed before the OSI Reference Model, and the Internet Engineering Task Force (IETF), which is responsible for the model and protocols developed under it, has never felt obligated to be compliant with OSI. While the basic OSI model is widely used in teaching, OSI, as presented as a seven-layer model, does not reflect real-world protocol architecture (RFC 1122) as used in the dominant Internet environment.

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