There was a well-known essay by venture capitalist Marc Andreessen published in The Wall Street Journal in 2011 in which he claimed that software is “eating the world.”

It’s a useful and colorful image and gives a sense of the extent to which software influences technology.

While Andreessen’s essay focused mostly on Silicon Valley startups, software continues to impact businesses across the board and around the globe. In addition to its role in consumer-facing applications and services, the software is hard at work behind the scenes and even influences how data centers operate.

Let’s start with virtualization. Virtualization was a big change for data center operators since it automated and streamlined server provisioning. However, virtualization didn’t truly modernize network and storage infrastructure for the next wave of business challenges stemming from technologies like cloud computing. Virtualization is focused entirely on compute/server workload and doesn’t concern itself with virtualizing networks or storage. Fully deployed virtualization (virtual machines, or VMs) didn’t change traditional networking or storage strategies.

Enter software-defined networking (SDN), a concept that brings the flexibility and economy of software to data center hardware.

SDN in the data center: Sustainable support for tomorrow’s applications

SDN is essentially a way of making a network programmable by decoupling control from the underlying hardware and assigning it instead to a software-based controller. To that end, protocols like OpenFlow have been pivotal in the evolution of SDN, since they are open standards that are not tied to any particular gear or vendor.

Accordingly, a network designed for SDN can be both flexible and vendor-neutral, which benefits data center operators, network operators, customers, and end users alike. With SDN, updating a policy or optimizing for a particular application is a matter of programming the software, rather than buying a new appliance or wrangling with a proprietary physical interface¹.

What are SDN benefits? Imagine the types of applications that have become viable only in the last few years, such as high-definition (HD) video and audio streaming as well as cloud-based productivity suites. These solutions are high-bandwidth and dynamic, meaning that they may sometimes require large amounts of resources that traditional, static networks can’t reliably deliver.

More specifically, here are five key benefits that SDN offers in the data center:

Dealing with big data: Organizations are keen to comb through large data sets using parallel processing, but doing so requires ample bandwidth. SDN can help by more effectively managing throughput and connectivity
Supporting cloud-based traffic: The rise of the cloud is one of the biggest trends in IT and telecom. Cloud is predicated on the idea of on-demand capacity and self-service, which SDN can dynamically deliver based on demand and availability of resources within the data center
Managing traffic to many IP addresses and virtual machines: SDN allows for dynamic routing tables so that routing prioritization can be achieved based on real-time network feedback, making control of virtual machines simpler to manage²
Making infrastructure scalable and agile: Using SDN, devices can be more easily added to the network, lowering the risk of service interruption. At the same time, SDN better fits the parallel processing and overall design of virtualized networks
Managing policy and security: SDN can be used to more efficiently and effectively propagate security policies throughout the network, including firewalling devices and other essential elements

With these benefits in mind, it makes sense that SDN in the data center is gaining traction. A recent report by SNS Research estimates that the SDN, Network Functions Virtualization (a developing technology aimed at virtualizing components in a service provider network), and network virtualization market will account for $10 billion of revenue in 2015, with an anticipated compound annual growth rate of 37% over the next 6 years. This estimate combines all types of SDN, including data centers, enterprise IT, and service provider network virtualization.

Hope these thoughts on SDN are helpful as you are thinking about your data center strategy. Of course, we at Digital Realty stand ready to assist you with designing, developing and delivering data center solutions that are agile, flexible, and adaptable to the evolution of your IT strategy, whether it includes SDN or not.

^{1. https://www.opennetworking.org/sdn-resources/sdn-definition}
^{2. https://www.datacenterknowledge.com/archives/2013/07/26/7-software-defined-networking-considerations/}

Case Study: Transbeam