With network functions virtualization (NFV) we are transforming the global communications network. Let me say that again: we are transforming the global communications network. This network, or really collection of networks, is retooled maybe once every ten or more years. Given that, it is a rare opportunity to be involved in such a broad scale network transformation. This is why I get so excited by NFV. NFV is a disruptive trend in the networking industry, and Tom and Ken are bringing you all the details you will need to find your way through this industry scale transformation. Whether you are a software developer, a network architect or engineer, or a network operator, this book will help you find your way through this transformation. At the core, business realities are behind the NFV movement. The networks built by communications service providers (CSPs) are under a relentless growing strain by ever-increasing data traffic. Both businesses and consumers are always connected to the network, serving and consuming data as we share information and services across the internet. Staggering growth in data traffic is largely driven by video streaming. One CSP cited 150,000% growth in data traffic from 2007–15 in the recent OpenStack Summit in Austin in April 2016. Many of the services consumers use are over the top (OTT) of the CSP’s network. OTT services such as messaging, voice, and video are a source of network strain but not a source of network revenue. Demand outpacing revenue represents an existential business risk for CSPs. To remain relevant and competitive it is time for CSPs to reinvent themselves.
Meanwhile, the IT industry is exploding with innovation. Technology shifts such as virtualization and the cloud, a focus on application programming interfaces (APIs) and automation, and services that are being continuously improved and updated fuel the IT industry’s ability to rapidly respond to changing business needs. This business agility is what draws consumers to these new services. Services that evolve quickly and converge on serving customers’ real interests have allowed the IT industry to push ahead and capture marketshare with OTT services. This same business agility is also the key to CSPs success. CSPs are looking to reinvent themselves by applying the innovation and learning from the IT industry to how they build and operate their own networks. The networking industry has historically worked through standards bodies to define the CSPs requirements and enable interoperability. This process is relatively slow. It can take years to go from initial Standards discussions to formal Standards to functional implementations to deploying those implementations in CSPs’ networks. While Standards and interoperability are still important, the process is too slow to be the only engine behind network innovation. But what does this mean in practice? It is time for the industry to collaborate more directly on not just the definition of the requirements, but also the actual underlying implementation. This is something that open source software and specifically the open source software development model excels at: fostering industry collaboration. It is no secret that the IT industry’s innovation is largely driven by open source software. Tom and Ken look at open source software projects such as OpenStack, OpenDaylight, and Open vSwitch as key building blocks for NFV. Fundamental to the NFV transformation is moving network functions trapped in function specific hardware to a more flexible fabric of compute, storage and network built from general purpose hardware – a cloud. This environment is software defined, meaning it can be quickly adjusted to new workloads using APIs and software automation. A network function becomes a piece of software executing like an application in a cloud. A simplistic view of NFV is simply virtualizing these hardware based applications, sometimes known as a “physical to virtual migration” or simply p2v. However, p2v alone is just a starting point. One challenge presented by NFV is providing sufficient packet processing efficiency in a cloud to make the transformation financially viable. A network service is typically composed of multiple network functions. Orchestrating the launch of a network service including directing network traffic through each of the network functions also provides some interesting challenges for NFV. Another challenge is providing the network Service Assurance expected by users when building from commodity infrastructure. Tom and Ken delve into these challenges in detail, looking at different industry efforts in both standards and open source.
What’s most exciting to me is that NFV is just the beginning. Significant industry trends such as Internet of Things (IoT) and 5G will be built on these next generation networks that are set in motion by NFV. Mainstream introduction of new technologies such as self-driving cars, augmented and virtual reality, and smart cities are examples of the kind of impact this new network will have on society. So coming up to speed on the terminology, the history, and evolution of NFV, and the details of how the industry is solving the challenges presented by NFV will serve you well. Tom and Ken have brought all of this information together, and I hope you enjoy learning from them as much as I have!
Chris Wright is Vice President and Chief Technologist at Red Hat where he is leading engineers who work on cloud computing, distributed storage, software defined networking and network functions virtualization, containers, machine learning, and continuous delivery. During his more than 20 years as a software engineer he has worked in the telecom industry on high availability and distributed systems and in the Linux industry on security, virtualization, and networking. He has been a Linux developer for over 15 years, most of that time spent deep in the Linux kernel. He is passionate about open source software serving as the foundation for next generation IT systems. He lives in sunny Portland, Oregon, where he is happily working with open source projects such as OpenDaylight, Open vSwitch, OPNFV, OpenStack, Open Container Initiative, and Cloud Native Computing Foundation.