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The TCP/IP Guide  9  The Open System Interconnection (OSI) Reference Model

History of the OSI Reference Model 1 The Benefits of Networking Models

Before getting into the details of how the OSI Reference Model works, I think it is a good idea to first discuss some of the basic issues related to reference models. In part, I want to explain why I place so much emphasis on the OSI model in this Guide, even going so far as to organize much of the document on the basis of this model. I also want you to understand why the model is important, and how it benefits networking not only on a conceptual level, but in reality as well.

So, in this section I describe several issues that relate to reference models in general terms, and of course, to the OSI Reference Model as well. I begin with some overview explanation of why networking models are beneficial, and why it is important for you to understand how the OSI model works. I then talk about how best to use the OSI Reference Model, and also contrast it to some “real-world” network architectures and protocol stacks.

History of the OSI Reference Model 1 The Benefits of Networking Models