Despite that, in two years I think the OpenFlow bubble will burst, and SDN will sink into the Trough Disillusionment on Gartner's Hype Cycle. It will be reborn as part of network management.
At the end of the day, someone in the audience asked a question along the lines of why Guido Appenzeller, CEO of Big Switch Networks, and Bruce Davie, chief service provider architect at Nicira, thought organizations would adopt OpenFlow in 12 to 18 months. They gave the same answer they have been giving all day: The adoption will be slow and will be used only where it fits, etc. I can't argue with that.
Or can I?
It was the end of the day. Maybe I was grumpy. Perhaps I wanted a cookie. Maybe I just wanted to make a statement. So I probably said the most words I had said all day (or something like this): "I think you two are being too optimistic. The cards are stacked against your two companies, OpenFlow and SDN. It took VMware about seven years to reach critical mass. IT shops are conservative. They don't want to monkey with the network running mission-critical services. They don't want to monkey with part of the network running mission-critical services, for fear something will break. That's a huge hurdle.
"Nor will the big networking vendors go away silently," I continued. "They are going to muddy the water, calling their APIs and SDK--none of which come close to 100% feature coverage--SDN, and even if they did have 10% coverage, it still wouldn't allow you to control flow paths. And let's not forget all the application vendors that had to be dragged kicking and screaming into server virtualization, thinking--wrongly--that their applications need eight cores and 32Gbytes of RAM when, in reality, they only needed 10% of that.
"They aren't going to want some new networking technology interconnecting their stuff, nor will any equipment vendors that have predefined hardware compatibility lists. Like storage vendors who, once you go off the HCL, point out, your kit doesn't comply with their best practice and you get no support until you bring it into line. Those factors have nothing to do with your products or technology--all of which may be great, creative and useful--but factors beyond your control are going to be a significant drag on adoption."
Davie made a funny but pointed statement, saying we don't want IT to give up its reliable and robust network. We want IT to keep it, and that way our stuff runs even better. While his answer is somewhat tongue-in-cheek, his point is that IT still wants fast, reliable hardware--Nicira just wants to manage it better.
I talked with Appenzeller a bit after the session, and he suggested I look at all the vendors lined up against Cisco, not to mention speak with potential customers wanting an alternative to the networking giant. I'm sure Appenzeller has had those conversations--you can hardly swing a Catalyst 6500 at Interop without hitting disgruntled Cisco customers. But are those customers disgruntled enough to either switch or even augment what they already have with Cisco?
No, I don't think so. Sure, big Internet companies like Google, cloud providers, online stores and other companies that make high demands on their networks and have the staff to engineer them can make a go of OpenFlow and SDN. But in my wholly unscientific opinion, I bet most companies aren't going to seriously consider either OpenFlow or SDN for some years--a long enough time for the VC money to dry up and larger vendors to pick up the carcasses along the Internet superhighway.
Don't get me wrong: The technology these SDN startups are developing is innovative, creative and challenges the status quo. They seem to be offering useful alternatives in how IT designs and runs their networks today. William Koss sums up what SDN startups are doing in "Missing the Point on Software Defined Networking (SDN)": "We should be intrigued that people are asking: 'Is there a better way?' ... This is also the reason why I think the architects, the revolutionaries, the entrepreneurs, the leaders of the next 20 years of networking are not working at the incumbents."
Of course, many of the problems that the SDN vendors state--VM mobility, the limited range of VLAN IDs, the inability to move L2/L3 networking among data centers and the inflexibility of current networking command and control--are problems faced only by cloud providers and a handful of large, large companies with big, global data centers. In other words: a rather small number of customers.
Many of the SDN vendors will be acquired by the incumbents, and perhaps the technology will make its way into shipping products. Until then, IT will continue to do whatever it is it does inefficiently.