Arista’s quarterly results might be showing us something important about the evolution of networking. The company reported stronger-than-expected revenue, but what surprised many on the Street and in the media was the comment that white-box switching wasn’t seen as competition. That might even be why revenues were better than expected, I think.
I also think that there should be no surprise here. Both SDN and NFV have struggled to show a benefit case, and in the case of NFV, thinking has evolved away from “capital cost” savings (meaning box costs) to operations and service agility benefits. SDN hasn’t made that transition, and so you could argue that it’s still stalled in a weak benefit situation.
If you start at the top, buyers have made it pretty clear that their preference for the network of the future would be a cheaper (capex-wise) version of the network of the past, but one that could then respond to additional economies in operations and additional revenue-generating or revenue-enhancing features. What they want is evolution and not revolution.
If you apply this to SDN, you see some immediate issues. Evolution, in infrastructure terms, means being able to introduce new technology in place of old where the “old” has been sufficiently depreciated. That means that to “evolve” to SDN you either have to make SDN devices serve in legacy missions, or you have to make legacy boxes serve in SDN missions.
Most of the vendors out there have already made their legacy devices capable of OpenFlow control, but obviously you don’t save anything by substituting a new box for an older version of the same box (unless the box is a lot cheaper now, which is what vendors are trying to avoid). That leaves making SDN work in place of legacy, and in order to do that you have to either buff up the white-box features to the point where it’s simply a new switch/router, or you have to create an enclave of new white boxes that look like a virtual legacy device and can replace a series of legacy devices.
I don’t think that SDN players, particularly white box players but even those who supply SDN controllers, have thought this through. They draw pictures of a network of white boxes without asking how we got there financially. The most credible model for SDN “evolution” is one where a series of legacy switches of various age are first migrated to SDN behavior using OpenFlow and then gradually replaced with white boxes. That’s possible, but the problem is that with an expected useful life for switches running around five years, the process is very slow. It also poses the largest possible risk right up front, when you switch from legacy to OpenFlow control.
It seems like the Arista strategy is smart given this situation. If you go to Arista’s website you have to dig to get anything on “SDN” at all. Their products look, in their PR face, pretty much like competitive legacy switching devices. Their switch literature concentrates on legacy support, meaning that it concentrates on introducing their products as substitutes for aging legacy switches from other vendors (Cisco comes to mind!) Yes, when you do this you get SDN capability, but most competitive switches also offer that in some form.
One of the questions this poses is what would drive SDN faster than it’s now being driven. Recall that analysts said SDN was no threat to Cisco, but NFV was. Might the rationale for this be that SDN really doesn’t have a convincing driver? Do we know what it might be?
We do, sort of. The only thing that can drive switching or anything else is benefits, and benefits have to be either reductions in TCO or improvements in revenue or (in the enterprise case) productivity. So we’re back to capex, opex, and service agility.
We’re back to the same problems with those drivers too, the same as NFV poses. SDN has a very narrow scope, as narrow as NFV. It’s addressed the bottom-layer technology issues and hasn’t yet gotten to the top layer. Sadly, businesses connect to networks at the top not at the bottom, which means that we’re still struggling to climb up to where users actually get something different and valuable.
OpenDaylight seems to be on the right track here, with a little help from a topic that’s rolled into NFV via its SDN integration—the intent model. The basic notion of ODL is that you give it a service in abstract form at a northbound interface (NBI), and it uses a variety of southbound interfaces (SBIs) to realize that service using whatever resources are provided. What makes ODL valuable versus “basic” OpenFlow is its ability to control devices that are not OpenFlow white-boxes, and to exploit that capability to tell a network evolution story.
The question for SDN is whether this NBI/SBI cooperation leads to evolution to SDN and not just to evolution. Remember, the buyer doesn’t particularly want new technology—that’s just a path to new risks. They want better benefits, including lower costs. Might we be seeing this whole abstraction thing creating a path to lower cost in another way—not through technology but through commoditization?
Premier players like Cisco get more for their devices, in part because of their brand. If we put an ODL mask on a device or device complex, does that legacy device brand shine through? Arista might be benefitting from the fact that it might not. They might be a specific example of buyer thinking of low-apple pure-device-cost gains now, and letting more profound benefit sources develop in their own time. Corporate-speak translation: Save a buck today and live to see tomorrow.
Cisco’s greatest threat, then, would be not the white boxes but the box-anonymizing architectures. Arista’s greatest benefit might still be its EOS, but the reason that might be a benefit is that it would allow Arista to do cheaper legacy devices today and evolve them if necessary to a more benefit-complicated future. Cisco could argue that’s what IOS and all their other three-letter acronyms do too, but they have to be cautious because if they encourage users to migrate faster than the 20%-per-year depreciation tradition would allow, they put more of their own devices up for grabs.
It’s hard to escape the conclusion that vendors in this space, from Arista to Cisco, are hurting themselves. Arista should be driving abstraction full-bore because anonymizing stuff in intent-based NBIs would make what’s underneath brand-insensitive. Cisco should be driving revolutionary benefits through its own application networking APIs to lance the boil of change and harness those benefits to justify continued investment in legacy infrastructure. Nobody is doing quite enough, which raises the chance that somebody will decide to do more, and by doing that generate a lot of excitement.