"Software defined networking (SDN) provides support for geographically distributed users, without having unused resources idle. This permits dynamic scaling of network services for peak times and supports service contraction during adverse operating conditions. This book presents a thoughtful discussion of the factors which led to the emergence of SDN, why SDN is vital to the growth and deployment of cloud-based computing systems, and what the impact of the SDN revolution will be. By tracing the data plane abstractions of layers into the SDN abstraction model, readers understand the importance of the SDN revolution"--