Chapter 5. The OSI Model: Start from the Beginning

So now that you know how to use a systematic method for solving problems, it’s time to apply that knowledge to a well-understood model of networking behavior, the Open System Interconnection (OSI) model. The OSI model, in case you are not familiar with it, is composed of seven layers that describe all the elements in a networked connection. Think of it like building a house: To paint the outside of the house, you’ve got to have walls. To have walls, you’ve got to have a floor, and to have a floor, you need a foundation. The OSI model describes the layers of abstraction you need to create interconnected systems.

We have found that when you really don’t know where to start, looking at the problem ...

Get Troubleshooting Linux® Firewalls now with the O’Reilly learning platform.

O’Reilly members experience books, live events, courses curated by job role, and more from O’Reilly and nearly 200 top publishers.