A book of this scope and size could not have been written without help from many people. We acknowledge much stimulation that came from early discussions with Markus Hofmann who headed the Bell Labs research effort in the Cloud. We have had incisive discussions on various topics of networking with Mark Clougherty, Vijay Gurbani, and Dimitri Stiliadis.

We have been much influenced and supported by David Amzallag (then CTO of CloudBand), particularly on the topic of operations and management.

Our first steps in addressing Cloud security were made together with Doug Varney, Jack Kozik, and Herbert Ristock (now with Genesys). We owe much of our understanding of the subject to our CloudBand colleagues—Ranny Haibi, Chris Deloddere, Mark Hooper, and Avi Vachnis. Sivan Barzilay has reviewed Chapter 7, to which she has contributed a figure; we also owe to her our understanding of TOSCA.

Peter Busschbach has reviewed Chapter 3 and provided insightful comments.

A significant impetus for this book came from teaching, and the book is intended to be an assigned text in a graduate course on Cloud Computing. Such a course, taught in the Stevens Institute of Technology, has been developed with much encouragement and help from Professor Daniel Duchamp (Director of Department of Computer Science), and many useful suggestions from Professor Dominic Duggan. Important insight, reflected in the course and in the book, came from graduate students who had served over the years as teaching assistants: Bo Ye (2012); Wa Gao (2013); Xiaofang Yu (2014); and Saurabh Bagde and Harshil Bhatt (2015).

It is owing to meeting (and subsequent discussions with) Professor Ruby Lee of Princeton University that we have learned of her research on NoHype—an alternative to traditional virtualization that addresses some essential security problems.

The past two years of working in the European Telecommunications Standardization Institute (ETSI) Network Function Virtualization (NFV) Industry Specification Group have contributed significantly to our understanding of the demands of the telecommunications industry. In particular, deep discussions of the direction of NFV with Don Clarke (Cable Labs), Diego Garcia Lopez (Telefonica), Uwe Michel (Deutsche Telekom) and Prodip Sen (formerly of Verizon and then HP) were invaluable in forming our perspective. Specifically on the subject of NFV security we owe much to all participants in the NFV Security group and particularly to Bob Briscoe (BT) and Bob Moskowitz (Verizon).

We got much insight into the US standards development on this topic in our conversation with George W. Arnold, then Director of Standards in National Institute of Standards and Technology (NIST).

It has been a great delight to work under the cheerful guidance of Ms Liz Wingett, our Project Editor at John Wiley & Sons. Her vigilant attention to every detail kept us on our feet, but the manuscript improved with every suggestion she made. As the manuscript was being prepared for production, Ms Audrey Koh, Production Editor at John Wiley & Sons, has achieved a feat truly worthy of the Fifth Labor of Hercules, going through the proofs and cleaning up the Augean Stables of stylistic (and, at times, even factual) inconsistencies.

To all these individuals we express our deepest gratitude.