I've worked at all levels of the computer networking field for over 20 years now and I enjoy helping newbies get started with understanding the technologies and the principles of those who advance in the I/T realm. I highly recommend Networking Made Easy by James Bernstein, as it shows you the basics of computer networking from the ground up, and makes it extremely easy to understand everything you need to get an extremely good start in networking.
If you're just starting out and you want a great bird's eye view of networking as your foundation, I highly recommend this book!
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