Sams Teach Yourself TCP/IP in 24 Hours, Third Edition

The Network Access Layer and the OSI Model

As Hour 2, “How TCP/IP Works” mentioned, TCP/IP is officially independent of the seven-layer OSI networking model, but the OSI model is often used as a general framework for understanding protocol systems. OSI terminology and concepts are particularly common in discussions of the Network Access layer because the OSI model provides additional subdivisions to the broad category of network access. These subdivisions reveal a bit more about the inner workings of this layer. The OSI model has been influential with computer networking vendors, and the recent trend toward multiprotocol standards such as NDIS and ODI (discussed later in this section) has accentuated the need for a common terminology that the ...