With the hype around software-defined networks (SDNs) having grown as high as it has, almost every vendor is looking for an angle to capitalize on the opportunity. I’ve noticed recently that many of the vendors, particularly the big-box vendors, are focused on the concept of "network programmability." While I agree that programmability is a component of SDN, it shouldn’t be the sole focus of the technology. As an example, Cisco has been pushing the Python-based ONE (Open Networking Environment), Juniper has JunosV App Engine and HP has its own programming environments. Like I said, I think these are important parts of the overall SDN solution, but it’s not aligned with where buyers are today.
I recently ran a survey with TechTarget and one of the questions asked was "How do you think SDNs can help your company?" The number one response, at 50% of the respondent base, was "simplify network architecture." The No. 2 response (46.9%) was "reduce network hardware costs." The third most popular response (45.4%) was to enable network management. Way down on the list, at 7.7%, was to "provide a more programmable network."
Programmability could be used to improve network management, but it really doesn’t have any impact on the first two options: simplification of architecture and reduction of hardware costs. Those problems are solved through the use of low-cost, standards-based switching hardware that is simple to deploy and manage. I’m not saying that the big box vendors are trying to slow innovation or aren’t taking SDNs seriously. In fact, it’s quite the opposite. The mainstream vendors do want to offer a credible SDN story, but they do need some level of vertical integration to keep the "end-to-end” value proposition intact.
For most mainstream companies, the limitations of a vertically integrated solution will probably be fine, at least in the near term. In fact, I’m not sure most mainstream companies would even know where to procure low-cost, non-brand-name network hardware. However, for those organizations with hyper-scale data centers where the network is the business, being able to cut the cost of switching through the use of low-cost, simplified network infrastructure can be significant. In a sense, it’s the same market where SeaMicro thrived by offering simpler, lower-cost rack servers.
While much of the industry will focus on the programmability of the network, the companies that want to leverage the cost benefit of SDNs now should think "open" first, and then look to leverage programmability once the architecture has been simplified and the overall network has become more manageable.