SDN: Software Defined Networks

Foreword by David Meyer

David Meyer

Although the ideas underlying software-defined networking (SDN) have only recently come into the public consciousness, a few of us who are active in the research, operator, and vendor communities immediately saw the applicability of SDN-like techniques to data center and service provider environments (and beyond). In addition to the explosion of innovative thinking going on in the research community, we also saw SDN as a programmatic way to optimize, monetize, and scale networks of all kinds.

In 2011, the first organization dedicated to the growth and success of SDN began with the Open Networking Foundation (ONF). Among its stated missions was to evolve the OpenFlow protocol from its academic roots to a commercially viable substrate for building networks and networking products. Within two years, the ONF’s membership had grown to approximately 100 entities, representing the diverse interest and expectations for SDN. Against this backdrop, many of us were looking at the wider implications of the ideas underlying SDN, and in the process, generalized SDN to include not only OpenFlow but other forms of network programmability as well.

Early on in this process, both Tom Nadeau and Ken Gray realized that SDN was really about general network programmability and the associated interfaces, protocols, data models, and APIs. Using this insight, they helped to organize the SDN Birds of a Feather session at IETF 82, in Taipei, to investigate this more general SDN model. At that meeting, Tom presented a framework for software-defined networks that envisioned SDN as a generalized mechanism for network programmability. This work encouraged the community to take a more general view of SDN and eventually led to the formation of the Interface to the Routing System Working Group in the IETF.

Since that time, in addition to their many contributions to Internet technologies, Tom and Ken have become well-respected senior members of the SDN community. They are active participants in the core SDN industry activities and develop products for the SDN market. Some of the key industry activities that Tom and Ken drive include the ONF, IETF, ETSI, industry events such as SDN Summit 2012/2013, as well as open source consortia such as the Open Daylight Project. This book draws on their deep understanding and experience in the field and offers a unique perspective on SDN. It will help you understand not only the technology but also how it is being developed, standardized, and deployed.

Tom and Ken are eminently qualified to give you a lucid understanding of the technology and the common-sense use and deployment of network programmability techniques. In particular, their book is an excellent and practical introduction to the fundamentals of SDN and is filled with innumerable anecdotes explaining the ideas and the background behind the development of SDN. So if you are interested in writing SDN applications, building SDN capable networks, or just understanding what SDN is, this book is for you!