Chapter 1. Networking Fundamentals

When it comes to theory, some of you out there might find it boring to read; so the first thing that may go through your mind is to skip this chapter. Don't do it. Even if you think that you know all the theoretical concepts, a recapitulation is good anytime.

Network professionals talk about protocols, devices, and software in terms of which OSI Layer they function at. When people talk about high-performance Layer 3 switches these days, they talk about switches that can perform OSI Layer 3 tasks and they expect you to know which tasks are at that layer. A simple deduction makes you realize that classic switches perform OSI Layer 2 functions.

Layer 3 switches are beyond the scope of this book, but that was a simple ...

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