Software Defined Networks are here to stay. But in a different form from what a lot of people might think. Unfortunately the industry has been focused until recently just on technical details but not on the value that SDN can bring to the table. The notion that SDN is just for data center or just for service providers is not true. SDN provides a lot of value to the Enterprise – from their Data Centers down to the mobile and wireless Edge.

Early days of SDN focused on implementation details like the OpenFlow protocol (for Southbound API) and promised that there are CapEx savings associated with the technology by using commodity ASICs. But those don’t scale to today’s requirements and so a several mainstream vendors are developing or using custom ASICs for the data plane already. Details on this will be a good content for a subsequent blog post.

I see that the main benefits of SDN are clearly the OpEx savings. SDN is about making the network more programmable to address business benefits like

• Improve network efficiency through centralized management and control along with higher degree of orchestration and automation
• Improve IT agility and network customization through fast and reliable application services, supporting the fast deployment of new applications
• Provide advanced analytics of all resources so that business can easily monitor and control these resources and make strategic business decisions.

A similar view on SDN and where the value lies can be also found on Fiercetelecom Website. Interesting read.

A recent poll during a industry webinar that I conducted with more than 700 registrations (integration partners and customers from different enterprise verticals) showed that: in response to the multiple choice question “What do you believe are the greatest benefits of SDN technology?” I saw good confirmation of this view:

So what SDN is really about? It provides a programmatic interface (aka Northbound API – typically SOAP or RESTful web services are used here) into the network fabric that allows network administrators or other IT teams and applications to provision new services on the fly, automate tasks and orchestrate different systems – physical and virtual.

An interesting survey about SDN in the enterprise confirms the use cases Enterprises want SDN but the webinar I did showed that quite a lot of enterprises have a good sense of what SDN is and what to focus on in all of the hype that goes on.

Another question during the same webinar came also to a similar conclusion. To the question “How would you rate the importance of a standards based south-bound protocol versus an open architecture with open north-bound API? “ the response was as follows:

So what are those new services? One can imagine a lot here – and this is the beauty of SDN, innovation can take place and much more rapid than in the traditional network – but I typically group them like this:To be honest, I expected more weight on the south bound standard but lets face it: the technology is still evolving at a rapid pace and the largest acquisition so far was based also on a proprietary technology.

• Network virtualization – as of now this seems to be the most common use case
• New service provisioning and application deployment – closely following network virtualization
• Traffic engineering – last but not least. But also very hard to accomplish even early adopters of OpenFlow like Google focused on that

Other services like load balancing or an easy to provision mirroring follow and it is up to the community to come up with new and innovative applications here. So the benefits are operational/functional and are tied to these new services. A higher degree of agility, new services, lower operational cost and a simplified network operation and design is the result.

In summary, I believe SDN should address on practical needs to create  a dynamic and agile network infrastructure aimed at the deployment of new services through common APIs. Increased network reliability, simplicity and security are a result the deployment of a solid SDN architecture as well. This results in a high and consistent user experience coupled with compelling OpEx savings. Last but not least more device, user, service and application visibility coupled with advanced analytics allow businesses to make quick and strategic business decisions and stay relevant.