Art Fewell, whose views I greatly respect, has written a very good post on Network World entitled “Open Networking: The Whale That Swallowed SDN“. It’s a great historical summary of SDN 2011-present, with some noteworthy areas of concern. I agree with the general thrust of Art’s thesis, yet at many points I found myself thinking “Yeah, but…” I started to write a few comments on the Network World page, but the comments turned into a page, so here we are.
Here’s what I really liked in Art’s piece:
- Art’s observation that some of the working groups are still caught in 2011 rhetoric is spot on. It’s easy to point fingers and throw rocks, but acknowledgement of the progress made by those who have to execute the original vision is absolutely warranted at this point.
- The fact the average enterprise is largely unrepresented in these conversations is certainly a problem. There’s a chicken-and-egg question to be kicked around there, but certainly if SDN only gets discussed in fairly unique contexts, it will remain something for most to think about at some point in the indefinite future (if ever). There’s a risk of the promise of the movement fizzling out if it’s confined to corner cases.
Here’s where I differ with Art, not with regard to his observations, but with his conclusions, which seem to come from a curiously hardware-centric perspective. Let me explain:
“Cisco and VMware for example are building comprehensive self-contained SDN/NFV ecosystems that are clearly separate and distinct. Unlike x86 where an investment in software does not create a dependency on an underlying hardware (or virtual hardware) provider…”
That’s because the dependency, the chokepoint, is the OS. It’s not that x86-based application ecosystems aren’t tied to a single vendor (they are–which is why MSFT has faced Anti-Trust so many times), it’s just not tied to a hardware platform. That doesn’t really make it “open”, from either a dev or user standpoint; it just allows the user to optimize the hardware purchase separately (from a still-limited number of options, it must be said) from the choices to be made between competing applications.
“If a vendor’s software doesn’t align with a business need, simply switch out the software leaving the considerable cost and complexity of the physical network, cable plant and topology in place, drastically reduc[es] consumer exposure to the risks of new technologies.”
Again, only from a hardware perspective. And hardware has always been less sticky than software, as discussed above.This is especially true of software that is an interaction point with a human user, and even more so if it governs processes, whether IT management applications or business software, which is why the new form of lock-in is not the NOS, but the layer above–the controller. Once you have rules and processes defined in ways that work within the context of one type of controller, it will be virtually impossible to swap out the software non-disruptively. The Big 4 infrastructure management vendors have been banking on this fact for years.
This does *not* mean that even proprietary controllers can not be developed to if vendors agree to northbound API standards. It is conceivable that a vendor-independent app ecosystem could be built on the foundation of such standards–though I concur that the temptation for any vendor will be to create apps that work especially well with their platforms. All this development work has to be monetized somehow.
“open networking is not the whale that swallowed SDN; SDN was never more than a piece of this much larger goal.”
I agree with second clause, though that was less explicitly articulated by all concerned three years ago than it is now. Which is why I disagree with the first clause–I think “open” is rapidly engulfing “SDN”. I know quite a few people–enterprise people–who have built their careers around Cisco, for example, but are increasingly convinced “open” is the way forward. This is partly why we keep seeing the debates about the continued value of the CCIE in particular. More than one analyst report has OpenDaylight taking a majority share in the controller market as it matures and while deployed infrastructure management has a very long tail, the energy around OpenStack makes that case fairly compellingly as well.
Overall, I’m more optimistic about this shift than a cynical chick like me normally would be. I think more inclusion of typical enterprises and their concerns is critical to getting this whole thing past the tipping point. As an industry we are frequently guilty of being caught up in tech for tech’s sake with little regard to the context in which the technology would live and the needs of the people who would use it. (Another Network World article on Google Glass provides another vivid illustration of this problem.) But I disagree with Art that the promise of Open Networking is being lost. Fortunately, I’m sure he’d love to be wrong.