Introduction
Dear Reader,
Thank you for buying (or considering) this book. By way of background, this book is the latest in a
series of Networking Simplified books that have covered topics such as basic networking with Cisco
Networking Simplified, and other titles that have taken a “simplified” approach to Voice over IP
(VoIP), security, and home networking.
If you are not familiar with the approach of the Networking Simplified books, the idea is to explain
networking concepts and technologies to people who are not intending to become technical experts,
but want to know what underlying networking technologies are and how they work at a high level.
This includes business and marketing folks, salespeople, investors, people who work in technical
companies but in nontechnical roles, and even technical people from different vocations who want a
cursory introduction to networking.
In others words, I wanted to write a book that explains how all this stuff works, and why it matters,
without assuming people needed to configure a router or set up a wireless network, and without
assuming the readers were dummies. The aim is to not go too deep but not be too light either.
To that end, I’ve now written (with the help of many people listed in the acknowledgments) a book on
the next big wave in networking: software-defined networking (SDN) and network functions
virtualization (NFV). My approach to this book is similar to the previous books in that I start with
some foundational topics, which in this case is virtualization. In fact, the first several sections of the
book focus on this because 1) it’s really important and 2) I did not think that there was a good
resource out there that took the same simplified approach. The book then moves into SDN and NFV,
and through it all are parts about cloud networks, virtualized data centers, and network virtualization.
Whiteboards
Also throughout this book, typically at the end of chapters, are “whiteboard” diagrams. These hand-
drawn (and then digitized) whiteboards are meant to capture key aspects of the chapter topics and
present those ideas as if they were drawn on a whiteboard.
In keeping with the at-a-glance feature of the previous Networking Simplified books, the whiteboards
are meant as enhancements to the text, and it is hoped that they will help aid in your understanding of
the topics they cover.
Who Is This Book For, and What Will You Get Out of It?
This book is mostly meant for nontechnical people who want to know what SDN, NFV, virtualization,
and cloud networking are about: what they are, how they all work, and why they are important. You
won’t walk away from this book knowing how to configure an SDN controller, but you will know
what one is and what it does. If you are a technical person with no exposure to these topics, this book
can serve as a high-level introduction.
How This Book is Organized
I’ve broken the book into ten sections, each covering a central theme. This allows you to bounce
around and pick one topic at time. If this is all brand new to you, tackling the topics in order is