Overall, I believe the book has done an excellent job covering most of the Software Defined Networking topics, perhaps sacrificing depth in terms of the breadth of topic coverage. I think the authors would be the first to agree that it is an impossible task to do both, therefore they made a choice to cover most topics without drilling too deep into them.
As a network engineer by trade for the last 14 years, I, as well as others feel that the Software Driven (or Defined) Networking is the biggest shift in mindset and technology in the last decade. The winners of this movement is sure to dominate the market for years to come. As such, there is a lot of buzz and movement surrounding the umbrella term of ‘SDN’. It is almost mind blowing to see the pace of change at each and all of the projects. OpenStack, for example, has moved on from Quantum to Neutron in such short months since publication, which contains no small change, mind you. So the readers should keep in mind that any written book would be out-of-date by the time it is done. This should be treated as a starting point that is like sampling the food at a buffet, but to sink your teeth into a particular topic, you have to spend more time diving into that particular topic.
As a reader, I come funnily anticipated looking the lenses of the authors on the topic at hand. If there is any suggestions, I would appreciate the book to be more focused on topics that the authors feel might be more important. It does not need to be correct as there is probably no right or wrong answer, but at least thru the supporting points we can understand the analytical process of the author. For example, VxLAN vs NVGRE, OpenStack vs. CloudStack, OpenFlow vs. Hybrid; tell us what you believe will prevail with supporting thesis. This is especially important in an emerging market such as SDN, where a new consortium seems to be forming by the week.
In conclusion, I feel the book is a fantastic starting point for any interested party to start diving into this exciting new world of SDN. Happy reading.