Daily Archives: June 5, 2012

Putting an ONF Conspiracy Theory to Rest

We know that the Open Networking Foundation (ONF) is controlled by the six major service providers that constitute its board of directors.

It is no secret that the ONF is built this way by design. The board members wanted to make sure that they got what they wanted from the ONF’s deliberations, and they felt that existing standards bodies, such as the IETF and IEEE, were gerrymandered and dominated by vendors with self-serving agendas.

The ONF was devised with a different purpose in mind — not to serve the interests of the vendors, but to further the interests of the service-provider community, especially the service providers who sit on the ONF’s board of directors. In their view, conventional networking was a drag on their innovation and business agility, obstructing progress elsewhere in their data centers and IT operations. Whereas compute and storage resources had been virtualized and orchestrated, networking remained a relatively costly and unwieldy fiefdom ruled by “masters of complexity” rummaging manually through an ever-expanding bag of ad-hoc protocols.

Organizing for Clout

Not getting what they desired from their networking vendors, the service providers decided to seize the initiative. Acting on its own,  Google already had done just that, designing and deploying DIY networking gear.

The study of political elites tells us that an organized minority comprising powerful interests can impose its will on a disorganized majority.  In the past, as individual companies, the ONF board members had been unable to counter the agendas of the networking vendors. Together, they hoped to effect the change they desired.

So, we have the ONF, and it’s unlike the IETF and the IEEE in more ways than one. While not a standards body — the ONF describes itself as a “non-profit consortium dedicated to the transformation of networking through the development and standardization of a unique architecture called Software-Defined Networking (SDN)” — there’s no question that the ONF wants to ensure that it defines and delivers SDN according to its own rules  And at its own pace, too, not tied to the product-release schedules of networking vendors.

In certain respects, the ONF is all about consortium of customers taking control and dictating what it wants from the vendor community, which, in this case, should be understood to comprise not only OEM networking vendors, but also ODMs, SDN startups, and purveyors of merchant silicon.

Vehicle of Insurrection?

Just to ensure that its leadership could not be subverted, though, the ONF stipulated that vendors would not be permitted to serve on its board of directors. That means that representatives of Cisco, Juniper, and HP Networking, for example, will never be able to serve on the ONF board.

At least within their self-determined jurisdiction, the ONF’s board members call all the shots. Or do they?

Commenting on my earlier post regarding Cisco’s SDN counterstrategy, a reader, who wished to remain anonymous (Anon4This1), wrote the following:

Regarding this point: “Ultimately, [Cisco] does not control the ONF.”

That was one of the key reasons for the creation of the ONF. That is, there was a sense that existing standards bodies were under the collective thumb of large vendors. ONF was created such that only the ONF board can vote on binding decisions, and no vendors are allowed on the board. Done, right? Ah, well, not so fast. The ONF also has a Technical Advisory Group (TAG). For most decisions, the board actually acts on the recommendations of the TAG. The TAG does not have the same membership restrictions that apply to the ONF board. Indeed, the current chairman of the TAG is none other than influential Cisco honcho, Dave Ward. So if the ONF board listens to the TAG, and the TAG listens to its chairman… Who has more control over the ONF than anyone? https://www.opennetworking.org/about/tag

Board’s Iron Grip

If you follow the link provided by my anonymous commenter, you will find an extensive overview of the ONF’s Technical Advisory Group (TAG). Could the TAG, as constituted, be the tail that wags the ONF dog?

My analysis leads me to a different conclusion.  As I see it, the TAG serves at the pleasure of the ONF board of directors, individually and collectively. Nobody on the TAG does so without the express consent of the board of directors. Moreover, “TAG term appointments are annual and the chair position rotates quarterly.” Whereas Cisco’s Dave Ward serves as the current chair, his term will expire and somebody else will succeed him.

What about the suggestion that the “board actually acts on recommendations of the TAG,” as my commenter asserts. In many instances, that might be true, but the form and substance of the language on the TAG webpage articulates clearly that the TAG is, as its acronym denotes, an advisory body that reports to (and “responds to requests from”) the ONF board of directors.  The TAG offers technical guidance and recommendations, but the board makes the ultimate decisions. If the board doesn’t like what it’s getting from TAG members, annual appointments presumably can be allowed to expire and new members can succeed those who leave.

Currently, two networking-gear OEMs are represented on the ONF’s TAG. Cisco is represented by the aforementioned David Ward, and HP is represented by Jean Tourrilhes, an HP-Labs researcher in Networking and Communication who has worked with OpenFlow since 2008. These gentlemen seem to be on the TAG because those who run the ONF believe they can make meaningful contributions to the development of SDN.

No Coup

It’s instructive to note the company affiliations of the other six members serving on TAG. We find, for instance, Nicira CTO Martin Casado, as well as Verizon’s Dave McDysan, Google’s Amin Vahdat, Microsoft’s Albert Greenberg, Broadcom’s Puneet Agarwal, and Stanford’s Nick McKeown, who also is known as a Nicira co-founder and serves on that company’s board of directors.

If any company has pull, then, on the ONF’s TAG, it would seem to be Nicira Networks, not Cisco Systems. After all, Nicira has two of its corporate directors serving on the ONF’s TAG. Again, though, both gentlemen from Nicira are highly regarded and esteemed SDN proponents, who played critical roles in the advent and development of OpenFlow.

And that’s my point. If you look at who serves on the ONF’s TAG, you can clearly see why they’re in those roles and you can understand why the ONF board members would desire their contributions.

The TAG as a vehicle for an internal coup d’etat at the ONF? That’s one conspiracy theory that I’m definitely not buying.

SDN Controller Ecosystems Critical to Market Success

Software-defined networking (SDN) is a relatively new phenomenon. Consequently, analogies to preceding markets and technologies often are invoked by its proponents to communicate key concepts. One oft-cited analogy involves the server-based solution stack and the nascent SDN stack.

In this comparison, server hardware equates to networking hardware, with the CPU instruction set positioned as analogous to the OpenFlow instruction set. Above those layers, the server operating system is said to be analogous to the SDN controller, which effectively runs a “network operating system.” Above that layer, the analogy extends to similarities between server OS and network OS APIs and to the applications that run atop both stacks.

Analogies and Implications

Let’s consider the comparison of the server operating system to the SDN controller.  While the analogy is apt, it carries implications that prospective early adopters of SDN need to fully understand. As we’ve discussed before, SDN controllers based on OpenFlow today carry no guarantees of interoperability. An application that runs on one controller might not be available (or run) on another controller, just as an application developed for a Windows server might not be available on Linux (and vice versa).

Moreover, we don’t know how difficult it will be to port applications from one OpenFlow-based controller to another. It could be a trivial exercise or an agonizing one. There are many nagging questions, far fewer answers.

Keep in mind that this is an entirely different matter from the question of interoperability between OpenFlow-based controllers and switches. Presuming the OpenFlow standard is adhered to and implemented correctly in all cases, OpenFlow-based controllers on the market today should be able to communicate with OpenFlow-based switches.

But interoperability (or lack thereof) is an unwritten book at the layers where the SDN controller (an NOS akin to a server-based operating system) and the NOS APIs reside.  The poses a potential problem for the market development of a viable SDN ecosystem, at least for the enterprise market. (It’s not as much of an issue for the gargantuan service providers that drive the agenda of the Open Network Foundation; those companies have ample resources and will make their own internal standardization decisions relating to controllers and practically everything else that falls under the SDN rubric.)

Controller Derby

At SDNCentral, no fewer than seven open-source OpenFlow controllers are listed. Three of those controllers are Java based: Beacon, Floodlight, and Jaxon. The other open-source OpenFlow controllers listed at SDNCentral are FlowER, NodeFlow, POX, and Trema.  Additionally, OpenFlow controllers have been developed by several companies, including NEC, BigSwitch Networks (which offers a commercial version of the Floodlight controller), and Nicira Networks, which has built on the foundation of the Onix controller.

Interestingly, Google and Ericsson also have based their controllers on Onix. In a blog post last summer, Nicira CTO Martin Casado described Onix as a “general SDN controller” rather than an OpenFlow controller. Casado admitted that he was devising terminology on the fly, but he defined a “general SDN controller as “one in which the control application is fully decoupled from both the underlying protocol(s) communicating with the switches, and the protocol(s) exchanging state between controller instances (assuming the controllers can run in a cluster).” So, OpenFlow could be part of the picture, but it doesn’t have to be there; another mechanism could substitute for it.

Casado conceded that Onix is the right controller for many environments, but not for others. Wrote Casado:

There have been multiple control applications built on Onix, and it is used in large production deployments in the data centers, as well as in the access and core networks. However, it is probably too heavyweight for smaller networks (the home or small enterprise), and it is certainly too complex to use as a basic research tool.

Horses for Courses

So, there are horses for courses, and there are controllers for applications. Early indications suggest that it will not be a one-size-fits-all world. Nonetheless, at the end of his blog post, Casado expressed that opinion that “standards should be kept away” from controller design, and that the market’s natural-selection process should be allowed to run its course.

Perhaps that is the right prescription. It seems too early for leaden-footed standards bodies, such as the IETF and IEEE, to intervene. Nevertheless, customers will have to be wary. They’ll have to do their research, perform due diligence, and thoroughly understand the strengths, weaknesses, and characteristics of candidate controllers. Without assured controller interoperability, customers that adopt and deploy applications on one controller might have considerable difficulty shifting their investment and their software elsewhere.

Of course, if Google and the other major service providers who rule the roost at ONF want to expedite matters, they could publicly and aggressively endorse one or two controller platforms as de facto standards. But that’s probably unlikely, for a variety of reasons. Even if it were to happen, as Casado points out, any controller that proves favorable at large cloud service providers might not be the best choice for enterprises, especially smaller ones.

Opening for Networking’s Old Guard

At this point, it’s not clear how the SDN controller market will shake out. SDN controllers will struggle for sustenance not only against each other, but also against networking’s conventional distributed control planes already on the market, as well as so-called hybrid approaches — whereby the data path is jointly controlled by the conventional box-based control planes as well as by server-based controllers — that will be articulated and promoted by the major networking vendors, all of whom are keen to retard “pure SDN’s” advance from the environs of the largest cloud service providers to those of enterprise buyers. (As mentioned previously, the hybrid-control approach also is perceived by the ONF as a transitional necessity for customers seeking to move from their networks as they are constituted today to future SDN architectures.)

In that regard, the big networking powers are fortunate that the ONF’s early mandate is focused primarily, if not exclusively, on the requirements of the large cloud-service providers that populate its board of directors. The ambiguity surrounding controllers and their interoperability (or lack thereof) represents another factor that will dissuade enterprise buyers from taking an early leap of faith into the arms of SDN purveyors.

The faster the SDN market sorts out a controller hierarchy — determining the suitability and market prevalence of certain controllers in specific application environments — the sooner valuable ecosystems will form and enterprises will take serious notice.

For now, though, a shakeout doesn’t appear imminent.