Which of the following is NOT part of the OSI model?

The Network Access Layer is not part of the OSI model; instead, it is a term associated with the TCP/IP model, which is another framework for understanding network architecture. The OSI model consists of seven distinct layers, which include the Transport Layer, Session Layer, and Presentation Layer among others.

In the OSI model, the layers are structured as follows:

1. Physical Layer

2. Data Link Layer

3. Network Layer

4. Transport Layer

5. Session Layer

6. Presentation Layer

7. Application Layer

Each of these layers plays a critical role in managing data communication. The Transport Layer is responsible for end-to-end communication and reliability, the Session Layer manages sessions between applications, and the Presentation Layer handles data translation and formatting. By understanding these layers, one can better grasp how data is transmitted across networks.