Category Archives: OpenFlow

Infrastructure Virtualization Versus Converged Infrastructure

While writing about software-defined networking (SDN) and what it makes possible, I have been thinking about how its essential premise, and the premise behind infrastructure virtualization, conflicts with visions of converged infrastructure promulgated by the leading systems vendors in the information-technology (IT) industry.

According to the Wikipedia definition, converged infrastructure encompasses servers, storage, networking gear, and software for IT infrastructure management, automation, and orchestration. Accordingly, converged infrastructure leverages pooled IT resources to facilitate automated resource provisioning in support of dynamic application workloads.

Hardware Pedigrees in Software World

Leading vendors, most with more hardware than software pedigrees, have sought to offer proprietary converged-infrastructure offerings that closely integrate the hardware elements with software-based management attributes. In this regard,  we can cite vendors such as Cisco (with a storage assist from EMC or NetApp), Hewlett-Packard, Dell, Hitachi Data Systems, Oracle (though networking remains on open question there),  and, perhaps to a lesser extent, IBM.

Now, let’s think about SDN and where it ultimately leads. Cisco would like us to believe that SDN, if it leads anywhere, will eventually take us to network programmability, with a heavy emphasis on the significance of a northbound API (or APIs).  Cisco says that the means — in this case, SDN — are not as important as the desired ends, networking programmability, and many of Cisco’s enterprise customers will doubtless agree.

SDN End Games

Another SDN outcome is network virtualization, which admittedly can also be achieved through other means. But an interesting aspect of SDN’s approach to network virtualization, with its decoupling of the network’s control and data planes, is that it results in the abstracting of software-based network intelligence from the underlying hardware-based network brawn. It’s a software paradigm taken to a logical extreme, with server-based software running at the network edge controlling an abstracted pool of no-frills networking hardware.

Indeed, this is one end game for SDN, first playing out in the data centers of the major cloud service providers that guide the affairs of the Open Networking Foundation (ONF), and then — at some indeterminate future point too difficult to forecast without a Ouija board and a bottle of scotch  — also at large enterprises worldwide.

Let’s elaborate further. SDN facilitates network virtualization, which in turn is harnessed and orchestrated by cloud-management software, which also manages virtualized compute and storage infrastructure. As we’ve seen already in the compute world of servers, it’s getting increasingly difficult for a vanity hardware vendor to earn a buck in a virtualized world. Many service providers have found that they can get boxes that satisfy their needs, at lower prices, directly from ODMs that often build servers for name-brand OEMs.  Storage is being virtualized, too.

Network’s Turn

And now it is the network’s turn.

In such a world, how much longer will it make sense for customers to achieve converged infrastructure from single-source vendors that equip their hardware with proprietary fripperies and hooks to facilitate lock-in? Again, we can see these trend playing out at large service providers. Some have begun buying their networking hardware off the rack from ODMs, saving not only on capital expenditures (certainly the case for servers), but also on operating expenses relating to the ongoing management of network infrastructure. It’s true that they’re trading one sort of complexity for another, pushing it up the stack and into software rather than an operational hardware, but it’s a trade-off they’re clearly willing to make, probably because they have the resources and skill sets to make it work (and pay).

Obviously that is not a recipe for everybody, certainly not for most enterprises today. But times are changing, and it isn’t inconceivable to foresee a day when the enterprise will be able to avail itself of third-party private-cloud software and management tools that will allow it to exploit a similar model of virtualized infrastructure.

Prescience Pays Off

In the big picture, as far as the established networking vendors are concerned, the ONF’s conception of SDN is about more than just OpenFlow, and even about more than network programmability. It’s about how SDN supports a model of network virtualization, in service to infrastructure virtualization, that significantly enfeebles hardware-based business models. Some of these hardware-oriented vendors will not successfully pivot to a model of virtualized infrastructure and software primacy.

On the other hand, some vendors have had the prescience to see this trend approaching on the horizon; they understand its inevitability, and they have positioned themselves better than others to survive, and perhaps even thrive, after the eventual market transition.

We’ll look at one of those vendors in a subsequent post.

SDN Focus Turns to Infrastructure

At this year’s SIGCOMM conference in Helsinki, Finland, a workshop called Hot Topics in Software-Defined Networking (HotSDN) will be held on August 13.  A number of papers will be presented as part of HotSDN’s technical program, but one has been written as a “call to arms for the SDN community.”

The paper is called: “Fabric: A Retrospective on Evolving SDN.” Its authors are Martin Casado, CTO of Nicira Networks; Teemu Koponen of the International Computer Science Institute (ICSI); Scott Shenker, a co-founder of Nicira Networks (along with Casado) and also a professor of computer science at University of California, Berkeley; and Amin Tootoonchian, a PhD candidate at the University of Toronto and a visiting researcher at ICSI.

SDN Fabrics

We’ll get to their definition of fabric soon enough, but let’s set the stage properly by explaining at the outset that the paper discusses SDN’s shortcomings and proposes “how they can be overcome by adopting the insight underlying MPLS,” which is seen as helping to facilitate an era of simple network hardware and flexible network control.

In the paper’s introductory section, the authors contend that “current networks are too expensive, too complicated to manage, too prone to vendor lock-in, and too hard to change. “ They write that the SDN community has done considerable research on network architecture, but not as much on network infrastructure, an omission that they then attempt to rectify.

Network infrastructure, the paper’s authors contend, has two components: the underlying hardware, and the software that controls the overall behavior of the network. Ideally, they write, hardware should be simple, vendor-neutral, and future-proof, while the control plane should be flexible.

Infrastructure Inadequacies

As far as the authors are concerned, today’s network infrastructure doesn’t satisfy any of those criteria, with “the inadequacies in these infrastructural aspects . . .  probably more problematic than the Internet’s architectural deficiencies.” The deficiencies cannot be overcome through today’s SDN alone, but a better SDN can be built by, as mentioned above, “leveraging the insights underlying MPLS.”

And that’s where network fabrics enter the picture. The authors define a network fabric as “a contiguous and coherently controlled portion of the network infrastructure, and do not limit its meaning to current commercial fabric offerings.” Later, they refer to a network fabric as “a collection of forwarding elements whose primary purpose is packet transport. Under this definition, a network fabric does not provide more complex network services such as filtering or isolation.”

Filtering, isolation, policy, and other network services will be handled in software at the network edge, while the fabric will serve primarily as a “fast and cheap” interconnect. The authors contend that we can’t reach that objective with today’s SDN and OpenFlow.

OpenFlow’s Failings

They write that OpenFlow’s inability to “distinguish between the Host-Network interface (how hosts inform the network of requirements) and the Packet-Switch interface (how a packet identifies itself to a switch) has resulted in three problems, the first of which is that OpenFlow, in its current form, does not “fulfill the promise of simplified hardware” because the protocol requires switch hardware to support lookups of hundreds of bits.

The second problem relates to flexibility. As host requirements evolve, the paper’s authors anticipate “increased generality in the Host-Network interface,” which will mean increasing the generality in . . . “matching allowed and the actions supported” on any every switch supported by OpenFlow. The authors are concerned that “needing functionality to be present on every switch will bias the decision towards a more limited feature set, reducing OpenFlow’s generality.”

The third problem, similar to the second, is that the current implementation of OpenFlow “couples host requirements to the network core behavior.” Consequently, if there is a change in external network protocols (such as a transition from IPv4 to IPv6), the change in packet matching would necessarily extend into the network core.

Toward a New Infrastructure

Accordingly, the authors propose a network fabric that borrows heavily from MPLS, with its labels and encapsulation, and that also benefits from proposed modifications to the SDN model and to OpenFlow itself. What we get is a model that includes a network fabric as “architectural building block” within SDN. A diagram illustrating this SDN model shows a source host connecting to an ingress edge switch, which then applies MPLS-like label-based forwarding within the “fabric elements.” On the other side of the fabric, an egress edge switch ensures that packets are delivered to the destination host. The ingress and egress edge switches answer to an “edge controller,” while a “fabric controller” controls the fabric elements.

The key properties associated with the SDN fabric are separation of forwarding and separation of control. Separation of forwarding is intended to simplify the fabric forwarding elements, but also to “allow for independent evolution of fabric and edge.” As for separation of control, I quote from the paper:

While there are multiple reasons to keep the fabric and the edge’s control planes separate, the one we would like to focus on is that they are solving two different problems. The fabric is responsible for packet transport across the network, while the edge is responsible for providing more semantically rich services such as network security, isolation, and mobility. Separating the control planes allows them each to evolve separately, focusing on the specifics of the problem. Indeed, a good fabric should be able to support any number of intelligent edges (even concurrently) and vice versa.

Two OpenFlows?

As the authors then write, “if the fabric interfaces are clearly defined and standardized, then fabrics offer vendor independence and . . . limiting the function of the fabric to forwarding enables simpler switch implementations.”

The paper goes on to address the fabric-service model, fabric path setup, addressing and forwarding in the fabric, and how the edge context is mapped to the fabric (the options are address translation and encapsulation, which is the authors’ favored mechanism.)

To conclude, the authors look at fabric implications, one of which involves proposed changes to OpenFlow. The authors prescribe an “edge” version of OpenFlow, more general than the current manifestation of the protocol, and a “core” version of OpenFlow that is similar to MPLS forwarding. The authors say the current OpenFlow is an “unhappy medium,” insufficiently general for the edge and not simple enough for the core. The authors say the generic “edge version of OpenFlow should aggressively adopt the assumption that it will be processed in software, and be designed with that freedom in mind.”

Refinements to the Model

In the final analysis, the authors believe their proposal to address infrastructure as well as architecture will result in an SDN model “where the edge processing is done in software and the core in simple (network) hardware,” the latter of which would deliver the joint benefits of reduced costs and “vendor neutrality. “

The paper essentially proposes a refinement to both OpenFlow and to the SDN architectural model. We might call it SDN 2.0, though that might seem a little glib and presumptuous (at least on my part). Regardless of what we call it, it is evident that certain elements in the vanguard of the SDN community continue to work hard to deliver a new type of cloud-era networking that delivers software-based services running over a brawny but relatively simple network infrastructure.

How will the broader SDN community and established vendors in network infrastructure respond? We won’t have to wait long to find out.

Addressing SDN Burnout

In the universe of staccato text bursts that is Twitter, I have diagnosed a recent exhaustion of interest in software defined networking (SDN).

To a certain degree, the burnout is understandable. It is a relatively nascent space, generating more in the way of passionate sound and fury than in commercial substance. Some Twitter denizens with a networking bent have even questioned whether an SDN market — involving buyers as well as sellers — actually exists.

On that score, the pointed skepticism has been refuted. SDN vendors, including Nicira Networks and Big Switch Networks, increasingly are reporting sales and customer traction. What’s more, market-research firms have detected signs of commercial life. International Data Corporation (IDC), for example, has said the SDN market will be worth a modest $50 million this  year,  but that it will grow to $200 million in 2013 and to $2 billion by 2016. MarketsandMarkets estimates that the global SDN market will expand from $198 million in 2012 to $2.10 billion in 2017, representing a compound annual growth rate (CAGR) of 60.43% during that span.  I’m sure other market measurers will make their projections soon enough.

But just what are they counting? SDN isn’t a specific product category, like a switch; it’s an architectural model. In IDC’s case, the numbers include SDN-specific switching and routing as well as services and software (presumably including controllers and the applications that run on them). MarketsandMarkets is counting  SDN “switching, controllers, cloud virtualization applications, and network virtualization security solutions.”

Still, established networking vendors will argue that the SDN hype is out of proportion with on-the-ground reality. In that respect, they can cite recent numbers from Infonetics Research that estimate global revenue derived from sales of data-center network equipment — the market segment SDN is likely to make most headway during the next several years — was worth $2.2 billion in the first quarter of 2012. Those numbers include sales of Ethernet switches, application delivery controllers (ADCs), and WAN-optimization appliances.

This is where things get difficult and admittedly subjective. If we’re considering where the industry and customers stand today, then there’s no question that SDN gets more attention than it warrants. Most of us, including enterprise IT staff, do not wish to live in the past and don’t have the luxury of looking too far into the future.

That said, some people have the job of looking ahead and trying to figure out how the future will be different from the present. In the context of SDN, those constituencies would include the aforementioned market researchers as well as venture capitalists, strategic planners, and technology visionaries. I would also include in this class industry executives at established and emerging vendors, both those directly involved in networking technologies and those that interact with networking infrastructure in areas such as virtualization and data-center management and orchestration.

For these individuals, SDN is more than a sensationalized will-o’-the-wisp.  It’s coming. The only question is when, and getting that timing right will be tremendously important.

I suppose my point here is that some can afford to be dismissive of SDN, but others definitely cannot and should not. Is interest in SDN overdone? That’s subjective, and therefore it’s your call. I, for one, will continue to pay close attention to developments in a realm that is proving refreshingly dynamic, both technologically and as an emerging market.

Cisco’s SDN Response: Mission Accomplished, but Long Battle Ahead

In concluding my last post, I said I would write a subsequent note on whether Cisco achieved its objectives in its rejoinder to software-defined networking (SDN) at the Cisco Live conference last week in San Diego.

As the largest player in network infrastructure, Cisco’s words carry considerable weight. When Cisco talks, its customers (and the industry ecosystem) listen. As such, we witnessed extensive coverage of the company’s Cisco Open Network Environment (Cisco ONE) proclamations last week.

Really, what Cisco announced with Cisco ONE was relatively modest and wholly unsurprising. What was surprising was the broad spectrum of reactions to what was effectively a positioning statement from the networking market’s leading vendor.

Mission Accomplished . . . For Now

And that positioning statement wasn’t so much about SDN, or about the switch-control protocol OpenFlow, but about something more specific to Cisco, whose installed base of customers, especially in the enterprise, is increasingly curious about SDN. Indeed, Cisco’s response to SDN should be seen, first and foremost, as a response to its customers. One could construe it as a cynical gesture to “freeze the market,” but that would not do full justice to the rationale. Instead, let’s just say that Cisco’s customers wanted to know how their vendor of choice would respond to SDN, and Cisco was more than willing to oblige.

In that regard, it was mission accomplished. Cisco gave its enterprise customers enough reason to put off a serious dalliance with SDN, at least for the foreseeable future (which isn’t that long). But that’s all it did. I didn’t see a vision from Cisco. What I saw was an effective counterpunch — but definitely not a knockout — against a long-term threat to its core market.

Cisco achieved its objective partly by offering its own take on network programmability, replete with a heavy emphasis on APIs and northbound interfaces; but it also did it partly by bashing OpenFlow, the open  protocol that effects physical separation of the network-element control and forwarding planes.

Conflating OpenFlow and SDN

In its criticism of OpenFlow, Cisco sought to conflate the protocol with the larger SDN architecture. As I and many others have noted repeatedly, OpenFlow is not SDN;  the two are not inseparable. It is possible to deliver an SDN architecture without OpenFlow. Even when OpenFlow is included, it’s a small part of the overall picture.  SDN is more than a mechanism by which a physically separate control plane directs packet forwarding on a switch.

If you listened to Cisco last week, however, you would have gotten the distinct impression that OpenFlow and SDN are indistinguishable, and that all that’s happening in SDN is a southbound conversation from a server-based software controller and OpenFlow-capable switches. That’s not true, but the Open Networking Foundation (ONF), the custodians of SDN and OpenFlow, has left an opening that Cisco is only too happy to exploit.

The fact is, the cloud service-provider principals steering the ONF see SDN playing a much bigger role than Cisco would have you believe. OpenFlow is a starting point. It is a means to, well, another means — because SDN is an enabler, too. What SDN enables is network virtualization and network programmability, but not how Cisco would like its customers to get there.

Cisco Knows SDN More Than OpenFlow

To illustrate my point, I refer you to the relatively crude ONF SDN architectural stack showcased in a white paper, Software-Defined Networking: The New Norm for Networks. If you consult the diagram in that document, you will see that OpenFlow is the connective tissue between the controller and the switch — what ONF’s Dan Pitt has described as an “open interface to packet forwarding” — but you will also see that there are abstraction layers that reside well above OpenFlow.

If you want an ever more detailed look at a “modern” SDN architecture, you can consult a presentation given by Cisco’s David Meyer earlier this year. That presentation features physical hardware at the base, with SDN components in the middle. These SDN components include the “forwarding interface abstraction” represented by OpenFlow, a network operation system (NOS) running on a controller (server), a “nypervisor” (network hypervisor), and a global management abstraction that interfaces with the control logic of higher-layer application (control) programs.

So, Cisco clearly knows that SDN comprises more than OpenFlow, but, in its statements last week at Cisco Live, the company preferred to use the protocol as a strawman in its arguments for Cisco-centric network programmability. You can’t blame Cisco, though. It has customers to serve — and to keep in the revenue- and profit-generating fold — and an enterprise-networking franchise to protect.

Mind the Gap

But why did the ONF leave this gap for Cisco to fill? It’s partly because the ONF isn’t overly concerned with the enterprise and partly because the ONF sees OpenFlow as an open, essential precondition for the higher, richer layers of the SDN architectural model.

Without the physical separation of the control plane from the forwarding plane, after all, some of the ONF’s service-provider constituency might not have been able to break free of vendor hegemony in their networks. What’s more, they wouldn’t be able to set the stage for low-priced, ODM-manufactured networking hardware built with merchant silicon.

As you can imagine, that is not the sort of change that Cisco can get behind, much less lead. Therefore, Cisco breaks out the brickbats and goes in hot pursuit of OpenFlow, which it then portrays as deficient for the purposes of far-reaching, north-and-south network programmability.

Exiting (Not Exciting) Plumbing

Make no mistake, though. The ONF has a vision, and it extends well beyond OpenFlow. At a conference in Garmisch, Germany, earlier this year, Dan Pitt, the ONF’s executive director, offered a presentation called “A Revolution in Networking and Standards,” and made the following comments:

“I think networking is going to become an integral part of computing in a way that makes it less important, because it’s less of a problem. It’s not the black sheep any longer. And the same tools you use to create an IT computing infrastructure or virtualization, performance, and policy will flow through to the network component of that as well, without special effort.

I think enterprises are going to be exiting technology – or exiting plumbing. They are not going to care about the plumbing, whether it’s their networks or the cloud networks that increasingly meet their needs, and the cloud services. They’re going to say, here’s the function or the feature I want for my business goal, and you make it happen. And somebody worries about the plumbing, but not as many people who worry about plumbing today. And if you’ve got this virtualized view, you don’t have to look at the plumbing. . . .

The operators are gradually becoming software companies and internet companies. They are bulking up on those skills. They want to be able to add those services and features themselves instead of relying on the vendors, and doing it quickly for their customers. It gives opportunities to operators that they didn’t have before of operating more diverse services and experimenting at low cost with new services.”

No Cartwheels

Again, this is not a vision that would have John Chambers doing cartwheels across the expansive Cisco campus.

While the ONF is making plans to address the northbound interfaces that are a major element in Cisco’s network programmability, it hasn’t done so yet. Even when it does, the ONF is unlikely to standardize higher-layer APIs, at least in the near term. Instead, those APIs will be associated with the controllers that get deployed in customer networks. In other words, the ONF will let the market decide.

On that tenet, Cisco can agree with the ONF. It, too, would like the market to decide, especially since its market presence — the investments customers have made in its routers and switches, and in its protocols and management tools — towers imperiously over the meager real estate being claimed in the nascent SDN market.

With all that Cisco network infrastructure deployed in customer networks, Cisco believes it’s in a commanding position to set the terms for how the network will deliver software intelligence to programmers of applications and management systems. Theoretically, that’s true, but the challenge for Cisco will be in successfully engaging a programming constituency that isn’t its core audience. Can Cisco do it? It will be a stretch.

Do They Get It?

All the while, the ONF and its service-provider backers will be advancing and promoting the SDN model and the network virtualization and programmability that accompany it. The question for the ONF is not whether its movers and shakers understand programmers — it’s pretty clear that Google, Facebook, Microsoft, and Yahoo are familiar with programmers — but whether the ONF understands and cares enough about the enterprise to make that market a priority in its technology roadmap.

If the ONF leaves the enterprise to the dictates of the Internet Engineering Task Force (IETF) and Institute of Electrical and Electronics Engineers (IEEE), Cisco is likely to maintain its enterprise dominance with an approach that provides some benefits of network programmability without the need for server-based controllers.

Meanwhile, as Tom Nolle, president of CIMI Corporation has pointed out, Cisco ONE also serves as a challenge to Cisco’s conventional networking competitors, which are devising their own answers to SDN.

But that is a different thread, and this one is too long already.

Understanding Cisco’s Relationship to SDN Market

Analysts and observers have variously applauded or denounced Cisco for its network-Cisco ONE programmability pronouncements last week.  Some pilloried the company for being tentative in its approach to SDN, contrasting the industry giant’s perceived reticence with its aggressive pursuit of previous emerging technology markets such as IP PBX, videoconferencing, and converged infrastructure (servers).

Conversely, others have lauded Cisco’s approach to SDN as far more aggressive than its lackluster reply to challenges in market segments such as application-delivery controllers (ADCs) and WAN optimization, where F5 and Riverbed, respectively, demonstrated how a tightly focused strategy and expertise above the network layer could pay off against Cisco.

Different This TIme

But I think they’ve missed a very important point about Cisco’s relationship to the emerging SDN market.  Analogies and comparisons should be handled with care. Close inspection reveals that SDN and the applications it enables represent a completely different proposition from the markets mentioned above.

Let’s break this down by examining Cisco’s aggressive pursuit of IP-based voice and video. It’s not a mystery as to why Cisco chose to charge headlong into those markets. They were opportunities for Cisco to pursue its classic market adjacencies in application-related extensions to its hegemony in routing and switching. Cisco also saw video as synergistic with its core network-infrastructure business because it generated bandwidth-intensive traffic that filled up existing pipes and required new, bigger ones.

Meanwhile, Cisco’s move into UCS servers was driven by strategic considerations. Cisco wanted the extra revenue servers provided, but it also wanted to preemptively seize the advantage over its former server partners (HP, Dell, IBM) before they decided to take the fight to Cisco. What’s more, all the aforementioned vendors confronted the challenge of continuing to grow their businesses and public-market stock prices in markets that were maturing and slowing.

Cisco’s reticence to charge into WAN optimization and ADCs also is explicable. Strategically, at the highest echelons within Cisco, the company viewed these markets as attractive, but not as essential extensions to its core business. The difficulty was not only that Cisco didn’t possess the DNA or the acumen to play in higher-layer network services — though that was definitely a problem — but also that Cisco did not perceive those markets as conferring sufficiently compelling rewards or strategic advantages to warrant the focus and resources necessary for market domination. Hence, we have F5 Networks and its ADC market leadership, though certainly F5’s razor-sharp focus and sustained execution factored heavily into the result.

To Be Continued

Now, let’s look at SDN. For Cisco, what sort of market does it represent? Is it an opportunity to extend its IP-based hegemony, like voice, video, and servers? No, not at all. Is it an adjunct market, such as ADCs and WAN optimization, that would be nice to own but isn’t seen as strategically critical or sufficiently large to move the networking giant’s stock-price needle? No, that’s not it, either.

So, what is SDN’s market relationship to Cisco?

Simply put, it is a potential existential threat, which makes it unlike IP PBXes, videoconferencing, compute hardware, ADCs, and WAN optimization. SDN is a different sort of beast, for reasons that have been covered here and elsewhere many times.  Therefore, it necessitates a different sort of response — carefully calculated, precisely measured, and thoroughly plotted. For Cisco, the ONF-sanctioned approach to SDN is not an opportunity that the networking giant can seize,  but an incipient threat to the lifeblood of its business that it must blunt and contain — and, whatever else, keep out of its enterprise redoubt.

Did Cisco achieve its objective? That’s for a subsequent post.

Why Established Networking Vendors Aren’t Leading SDN Charge

Expressing equal parts exasperation and incredulity, Greg Ferro wonders why industry-leading networking vendors aren’t taking the innovative initiative in offering compelling strategies for software-defined networking (SDN).

The answer seems clear enough.

Although applications will be critical to the long-term commercial success of SDN, Google and the other movers and shakers that direct the affairs of the Open Networking Foundation (ONF) originally were drawn to SDN because they were frustrated with the lack of responsiveness and innovation from established vendors. As a result, they devised a networking model that not only separated the control and data planes of network elements, but that also, in the word’s of Google’s Amin Vahdat, separated the “ evolution path for (network) hardware and software.”

Two Paths

Until now, those evolutionary paths have been converged and constrained inside the largely propriety boxes of networking vendors. Google and its confreres with the ONF perceived that state of affairs as the yoke of vendor oppression. The network, slow to evolve and innovate, was getting in the way of progress.  All the combustible ingredients of a cloud-service provider insurrection had cohered. Google, taking the lead in organizing the other major service providers under the rubric of the ONF, lit the fuse.

The effects of the explosion are just being felt, and the reverberations will echo for some time. The big service providers, and perhaps many smaller ones, are gravitating away from the orbit of networking’s ancien regime. The question now is whether enterprises will follow. At some point, that probably will happen, but how and when it will unfold are less clear. Enterprises, unlike the board members of the ONF, are too diverse and prolific to organize in pursuit of common interests. Accordingly, vendors are still able to set the enterprise agenda.

But enterprises will notice the benefits that SDN is capable of conferring, and the ONF’s overlords will seek to cultivate and sustain an ecosystem that can deliver parallel hardware and software innovation. Google, for example, has indicated that while it develops its own networking hardware today, it would be amenable to buying OpenFlow switches from the vendor community. Those switches, like to carry lower margins and prices than the gear sold by the major networking vendors, will probably come from ODMs using merchant silicon from Broadcom, Marvell, Fulcrum (Intel), and others.

Money’s in the Software

The major networking vendors are saying that the cleavage of the control and data planes is not a big deal, that it’s not necessary or isn’t a critical requirement for innovation and network programmability. Perhaps there is some merit to their arguments, but there’s no question that the separation of the control and data planes is not in their business interests. If some their assertions have merit, they also are self-serving.

Cisco, as we’ve discussed before, might be able to develop software, but its business model is predicated on the sale of routers and switches. Effectively, it would have to remake itself comprehensively to recast itself as a vendor of server-based controllers (software) and the applications the run on them. A proprietary hardware box, whether a server or switch, isn’t what the ONF wants.

If the ONF’s SDN vision prevails, the money is in software: server-based controllers, applications, management/orchestration frameworks, and so on. Successful vendors not only will have to be proficient at developing software; they’ll also have to be skilled at marketing and selling it. They’ll have to build their businesses around it.

This is the challenge the major networking vendors confront. It’s why they aren’t leading the SDN charge, and it also is why they are attempting to co-opt and subvert it.

Tidbits: Oracle-Arista Rumor, Controller Complexity, More Cisco SDN

This Week’s Rumor

Rumors that Oracle is considering an acquisition of Arista Networks have circulated this week. They’re likely nothing more than idle chatter. Arista has rejected takeover overtures previously, and it seems determined to go the IPO route.

Controller Complexity

Lori MacVittie provides consistently excellent blogging at F5 Networks’ DevCentral. In a post earlier this week, she examined the challenges and opportunities facing OpenFlow-based SDN controllers. Commenting on the code complexity of controllers, she writes the following:

This likely means unless there are some guarantees regarding the quality and thoroughness of testing (and thus reliability) of OpenFlow controllers, network operators are likely to put up a fight at the suggestion said controllers be put into the network. Which may mean that the actual use of OpenFlow will be limited to an ecosystem of partners offering “certified” (aka guaranteed by the vendor) controllers.

It’s a thought-provoking read, raising valid questions, especially in the context of enterprise customers.

Cisco SDN

Last week, Cisco and Morgan Stanley hosted a conference call on Cisco’s SDN strategy. (To the best of my knowledge, Morgan Stanley doesn’t have one — yet.)  Cisco was represented on the call by David Ward, VP and chief architect of the company’s Service Provider Division; and by Shashi Kiran, senior director of market management for Data Center/Virtualization and Enterprise Switching Group.

The presentation is available online. It doesn’t contain any startling revelations, and it functions partly as a teaser for forthcoming product announcements at CiscoLive in San Diego. Still, it’s worth a perusal for those of you seeking clues on where Cisco is going with its SDN plans. If you do check it out, you’ll notice on side three that a number of headlines are featured attesting to the industry buzz surrounding SDN.  Two bloggers are cited in that slide: Greg Ferro (EtherealMind) and, yes, yours truly, who gets cited for a recent interpretation of Cisco’s SDN maneuverings.