Subscription Defined Networking

Cisco’s big announcement this week ahead of Cisco Live was their new Intent-based Networking push. This new portfolio does include new switching platforms in the guise of the Catalyst 9000 series, but the majority of the innovation is coming in the software layer. Articles released so far tout the ability of the network to sense context, provide additional security based on advanced heuristics, and more. But the one thing that seems to be getting little publicity is the way you’re going to be paying for software going forward.

The Bottom Line

Cisco licensing has always been an all-or-nothing affair for the most part. You buy a switch and you have two options – basic L2 switching or everything the switch supports. Routers are similar. Through the early 15.x releases, Cisco routers could be loaded with an advanced image that ran every service imaginable. Those early 15.x releases gave us some attempts at role-based licensing for packet, voice, and security device routers. However, those efforts were rolled back due to customer response.

Shockingly, voice licensing has been the most progressive part of Cisco’s licensing model for a while now. CallManager 4.x didn’t even bother. Hook things up and they work. 5.x through 9.x used Device License Units (DLUs) to help normalize the cost of expensive phones versus their cheaper lobby and break room brethren. But even this model soon gave way to the current Unified Licensing models that attempt to bundle phones with software applications to mimic how people actually communicate in today’s offices.

So where does that leave Cisco? Should they charge for every little thing you could want when you purchase the device? Or should Cisco leave it wide open to the world and give users the right to decide how best to use their software? If John Chambers had still been in charge of Cisco, I know the answer would have been very similar to what we’ve seen in the past. Uncle John hated the idea of software revenue cannibalizing their hardware sales. Like many stalwarts of the IT industry, Chambers believed that hardware was king and software was an afterthought.

Pay As You Go

But Chuck Robbins has different ideas. Alongside the new capabilities of Cisco’s Intuitive Network plan they have also introduced a software subscription model. Now, if you want to use all these awesome new features for the future of the network according to Cisco you are going to pay for them. And you’re going to pay every year you use them.

It’s not that radical of a shift in mindset if you look at the market today. Cable subscriptions are going away in favor of specialized subscriptions to specific content. Custom box companies will charge you a monthly fee to ship you random (and not-so-random) items. You can even set up a subscription to buy essential items from Amazon and Walmart and have them shipped to your home regularly.

People don’t mind paying for things that they use regularly. And moving the cost model away from capital expenditure (CapEx) to an operational expenditure (OpEx) model makes all the sense in the world for Cisco. Studies from industry companies like Infinity Research have said that Infrastructure as a Service (Iaas) growth is going to be around 46% over the next 5 years. That growth money is coming from organizations shift CapEx budget to OpEx budget. For traditional vendors like Cisco, EMC, and Dell, it’s increasingly important for them to capture that budget revenue as it moves into a new pool designed to be spent a month or year at a time instead of once every five to seven years.

The end goal for Cisco is to replace those somewhat frequent hardware expenditures with more regular revenue streams from OpEx budgets. If you’re nodding your head and saying, “That’s pretty obvious…” you are likely from the crowd that couldn’t understand why Cisco kept doubling down on bigger, badder switching during the formative years of SDN. Cisco’s revenue model has always looked a lot like IBM and EMC. They need to sell more boxes more frequently to hit targets. However, SDN is moving the innovation away from the hardware, where Cisco is comfortable, and into the software, where Cisco has struggled as of late.

Software development doesn’t happen in a vacuum. It doesn’t occur because you give away features designed to entice customers into buying a Nexus 9000 instead of a Nexus 6000. Software development only happens when people are paying money for the things you are developing. Sometimes that means that you get bonus features that they figure out in the process of making the main feature. But it surely means that the people focused on making the software want to get it right the first time instead of having to ship endless patches to make it work right eventually. Because if your entire revenue model comes from software, it had better be good software that people want to buy and continue to pay for.


Tom’s Take

I think Chuck Robbins is dragging Cisco into the future kicking and screaming. He’s streamlined the organization by getting rid of the multitude of “pretenders to the throne” and tightening up the rest of the organization from a collection of competing business units into a logically organized group of product lines that can be marketed. The shift toward a forward-looking software strategy built on recurring revenue that isn’t dependent on hardware is the master stroke. If you ever had any doubts about what kind of ship Chuck was going to sail, this is your indicator.

In seven years, we’re not going to be talking about Cisco in the same way we did before. Much like we don’t talk about IBM like we used to. The IBM that exists today bears little resemblance to Tom Watson’s company of the past. I think that the Cisco of the future will bear the same superficial resemblance to John Chamber’s Cisco as well. And that’s for the better.

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Cisco and Viptela – The Price of Development Debt

Cisco finally pulled themselves into the SD-WAN market by acquiring Viptela on Monday. Viptela was considered to be one of, if not the leading SD-WAN vendor in the market. That Cisco decided to pick them as an acquisition target isn’t completely surprising. But one might wonder why?

IWANna New Debt

Cisco’s premier strategy for SD-WAN up until last week was IWAN. This is their catch-all solution designed to take the various component pieces being offered by SD-WAN solutions and replicate them on Cisco hardware. IWAN has served as a vehicle for Cisco to push things like the APIC-EM solution, Cisco ONE licensing, and a variety of other enhanced technologies like NBAR and PfR.

Cisco has packaged these technologies together because they have spent a couple of decades building these protocols up to be the best at what they do in the industry. NBAR was the key to application QoS years ago. PfR and OER were the genesis of Cisco having the ability to intelligently route packets to destinations. These protocols have formed the cornerstone of their platform for many, many years.

So why is IWAN such a mess? If you have the best of breed technology built into a router that makes the packets fly across the Internet at lightning speeds how is it that companies like Viptela were eating Cisco’s lunch in the SD-WAN space? It’s because those same best-of-breed protocols are to blame for the jigsaw puzzle of IWAN.

If you are the product manager for a protocol like NBAR or PfR, you want it to be adopted by as many people as possible. Wide adoption guarantees you’re going to have a job tomorrow or even next year. The people working on EIGRP and OSPF are safe. But if you get left behind technologically, you’re in for rough seas. Just ask the folks that managed LANE. But if you can attach yourself to a movement that’s got some steam, you’re in the drivers seat.

At the same time, you want your protocol or product to be the best at what it does. And sometimes being the best means you don’t compromise. That’s great when you are the only thing running on the system. But when you’re trying to get protocols to work together to create something bigger, you often find that compromises are not just a good idea, they’re necessary. But how do you handle it when the product manager for NBAR and the product manager for IP SLA get into a screaming match over who is going to blink first?

Using existing protocols and products is a great idea because it means you don’t have to reinvent the wheel every time you design something. But, with that wheel comes the technical debt of development. Given the chance to reuse something that thousands, if not millions, of dollars of R&D has gone into, companies like Cisco will jump at the chance to get some more longevity out of a protocol.

Not Pokey, But Gumby

Now, lets look at a scrappy startup like Viptela. They have to build their protocols from the ground up. Maybe they have the opportunity of leveraging some open source projects or some basic protocol implementations to get off the ground. That means that they are starting from essentially square one. It also means they are starting off with very little technical and development debt.

When Viptela builds their application monitoring stack or their IPSec VPN stack, they aren’t trying to build the best protocol for every possible situation that could ever be encountered by a wide variety of customers. They are just trying to build a protocol that works. And not just a protocol that works on its own. They want a protocol that works with everything else they are building.

When you’re forced to do everything from scratch, you find that you avoid making some of the same choices that you were forced to make years ago. The lack of technical and development debt also means you can take a new direction with things. Don’t want to support pre-shared key IPSec VPNs? Don’t build it into the protocol. Don’t care to have some of the quirks of PfR? Build something different that meets your needs. You have complete control.

Flexibility is why SD-WAN vendors were able to dominate the market for the past two years. They were able to adapt and change quickly because they didn’t need to keep trying to make systems integrate on top the tech and dev debt they incurred during the product lifecycle. That lets them concentrate on features that customers want, not on trying to integrate features that management has decreed must be included because the product manager was convincing in the last QBR.


Tom’s Take

In the end, the acquisition of Viptela by Cisco was as much about reduction of technical and development debt in their SD-WAN offerings as it was trying to get ahead in the game. They needed something that could be used as-is without the need to rely on any internal development processes. I alluded to this during our Network Collective Off-The-Cuff show. Without the spin-out model available any longer, Cisco is going to have to start making tough decisions to get things like this done. Either those decisions are made via reduction of business units without integration or through larger dollar signs to acquire solutions to provide the cohesion they need.

The Future Of SDN Is Up In The Air

The announcement this week that Riverbed is buying Xirrus was a huge sign that the user-facing edge of the network is the new battleground for SDN and SD-WAN adoption. Riverbed is coming off a number of recent acquisitions in the SDN space, including Ocedo just over a year ago. So, why then, would Riverbed chase down a wireless company when they’re so focused on the wiring behind the walls?

The New User Experience

When SDN was a pile of buzzwords attached to an idea that had just come out of Stanford, a lot of people were trying to figure out just what exactly SDN could offer them in terms of their network. Things like network slicing were the first big pieces to be put up before things like orchestration, programmability, and APIs were really brought to the fore. People were trying to figure out how to make this hot new thing work for them. Well, almost everyone.

Wireless professionals are a bit jaded when it comes to SDN. That’s because they’ve seen it already in the form of controller-based solutions. The idea that a central device can issue commands to remote access devices and control configurations easily? Airespace was doing that over a decade ago before they got bought by Cisco. Programmability is a moot point to people that can import thousands of access points into a device and automatically have new SSIDs being broadcast on them all in a matter of seconds. Even the new crop of “controllerless” wireless systems on the market still have a central control infrastructure that sends commands to the APs. Much like we’ve found in recent years with SDN, removing the control plane from the data plane path has significant advantages.

So, what would it take to excite wireless pros about SDN? Well, as it turns out, the issue comes down to the user side of the equation. Wireless networks work very well in today’s enterprise. They form the backbone of user connectivity. Companies like Aruba are experimenting with all-wireless offices. The concept is crazy at first glance. How will users communicate without phones? As it turns out, most of them have been using instant messengers and soft phone programs for years. Their communications infrastructure has changed significantly since I learned how to install phone systems years ago. But what hasn’t changed is the need to get these applications to play nicely with each other.

Application behavior and analysis is a huge selling point for SDN and, by extension, SD-WAN. Being able to classify application traffic running on a desktop and treat it differently based on criteria like voice traffic versus web browsing traffic is huge for network professionals. This means the complicated configurations of QoS back in the day can be abstracted out of the network devices and handled by more intelligent systems further up the stack. The hard work can be done where it should be done – by systems with unencumbered CPUs making intelligent decisions rather than by devices that are processing packets as quickly as possible. These decisions can only be made if the traffic is correctly marked and identified as close to the point of origin as possible. That’s where Riverbed and Xirrus come into play.

Extending Your Brains To Your Fingers

By purchasing a company like Xirrus, Riverbed can build on their plans for SDN and SD-WAN by incorporating their software technology into the wireless edge. By classifying the applications where they live, the wireless APs can provide the right information to the SDN processes to ensure traffic is dealt with properly as it flies through the network. With SD-WAN technologies, that can mean making sure the web browsing traffic is sent through local internet links when traffic meant for main sites, like communications or enterprise applications, can be sent via encrypted tunnels and monitored for SLA performance.

Network professionals can utilize SDN and SD-WAN to make things run much more smoothly for remote users without the need to install cumbersome appliances at the edge to do the classification. Instead, the remote APs now become the devices needed to make this happen. It’s brilliant when you realize how much more effective it can be to deploy a larger number of connectivity devices that contain software for application analysis than it is to drop a huge server into a branch office where it’s not needed.

With the deployment of these remote devices, Riverbed can continue to build on the software side of technology by increasing the capabilities of these devices while not requiring new hardware every time a change comes out. You may need to upgrade your APs when a new technology shift happens in hardware, like when 802.11ax is finally released, but that shouldn’t happen for years. Instead, you can enjoy the benefits of using SDN and SD-WAN to accelerate your user’s applications.


Tom’s Take

Fortinet bought Meru. HPE bought Aruba. Now, Riverbed is buying Xirrus. The consolidation of the wireless market is about more than just finding a solution to augment your campus networking. It’s about building a platform that uses wireless networking as a delivery mechanism to provide additional value to users. The spectrum part of wireless is always going to be hard to do properly. Now, the additional benefit of turning those devices into SDN sensors is a huge value point for enterprise networking professionals as well. What better way to magically deploy SDN in your network than to flip a switch and have it everywhere all at once?

Do Network Professionals Need To Be Programmers?

With the advent of software defined networking (SDN) and the move to incorporate automation, orchestration, and extensive programmability into modern network design, it could easily be argued that programming is a must-have skill. Many networking professionals are asking themselves if it’s time to pick up Python, Ruby or some other language to create programs in the network. But is it a necessity?

Interfaces In Your Faces

The move toward using API interfaces is one of the more striking aspects of SDN that has been picked up quickly. Instead of forcing information to be input via CLI or information to be collected from the network via scraping the same CLI, APIs have unlocked more power than we ever imagined. RESTful APIs have giving nascent programmers the ability to query devices and push configurations without the need to learn cumbersome syntax. The ability to grab this information and feed it to a network management system and analytics platform has extended the capabilites of the systems that support these architectures.

The syntaxes that power these new APIs aren’t the copyrighted CLIs that networking professionals spend their waking hours memorizing in excruciating detail. JUNOS and Cisco’s “standard” CLI are as much relics of the past as CatOS. At least, that’s the refrain that comes from both sides of the discussion. The traditional networking professionals hold tight to the access methods they have experience with and can tune like a fine instrument. More progressive networkers argue that standardizing around programming languages is the way to go. Why learn a propriety access method when Python can do it for you?

Who is right here? Is there a middle ground? Is the issue really about programming? Is the prattle from programming proponents posturing about potential pitfalls in the perfect positioning of professional progress? Or are anti-programmers arguing against attacks, aghast at an area absent archetypical architecture?

Who You Gonna Call?

One clue in this discussion comes from the world of the smartphone. The very first devices that could be called “smartphones” were really very dumb. They were computing devices with strict user interfaces designed to mimic phone functions. Only when the device potential was recognized did phone manufacturers start to realize that things other than address books and phone dialers be created. Even the initial plans for application development weren’t straightforward. It took time for smartphone developers to understand how to create smartphone apps.

Today, it’s difficult to imagine using a phone without social media, augmented reality, and other important applications. But do you need to be a programmer to use a phone with all these functions? There is a huge market for smartphone apps and a ton of courses that can teach someone how to write apps in very little time. People can create simple apps in their spare time or dedicate themselves to make something truly spectacular. However, users of these phones don’t need to have any specific programming knowledge. Operators can just use their devices and install applications as needed without the requirement to learn Swift or Java or Objective C.

That doesn’t mean that programming isn’t important to the mobile device community. It does mean that programming isn’t a requirement for all mobile device users. Programming is something that can be used to extend the device and provide additional functionality. But no one in an AT&T or Verizon store is going to give an average user a programming test before they sell them the phone.

This, to me, is the argument for network programmability in a nutshell. Network operators aren’t going to learn programming. They don’t need to. Programmers can create software that gathers information and provides interfaces to make configuration changes. But the rank-and-file administrator isn’t going to need to pull out a Java manual to do their job. Instead, they can leverage the experience and intelligence of people that do know how to program in order to extend their network functionality.


Tom’s Take

It seems like this should be a fairly open-and-shut case, but there is a bit of debate yet left to have on the subject. I’m going to be moderating a discussion between Truman Boyes of Bloomberg and Vijay Gill of Salesforce around this topic on April 25th. Will they agree that networking professionals don’t need to be programmers? Will we find a middle ground? Or is there some aspect to this discussion that will surprise us all? I’ll make sure to keep you updated!

There Won’t Be A CCIE: SDN. Here’s Why

There’s a lot of work that’s been done recently to bring the CCIE up to modern network standards. Yusuf and his team are working hard to incorporate new concepts into the written exam. Candidates are broadening their horizons and picking up new ideas as they learn about industry stalwarts like OSPF and spanning tree. But the biggest challenge out there is incorporating the ideas behind software defined networking (SDN) into the exam. I don’t believe that this will ever happen. Here’s why.

Take This Broken Network

If you look at the CCIE and what it’s really testing, the exam is really about troubleshooting and existing network integration. The CCIE introduces and tests on concepts like link aggregation, routing protocol redistribution, and network service implementation. These are things that professionals are expected to do when they walk in the door, either as a consultant or as someone advising on the incorporation of a new network.

The CCIE doesn’t deal with the design of a network from the ground up. It doesn’t task someone with coming up with the implementation of a greenfield network from scratch. The CCIE exam, especially the lab component, only tests a candidate on their ability to work on something that has already exists. That’s been one of the biggest criticisms of the CCIE for a very long time. Since the knowledge level of a CCIE is at the highest level, they are often drafted to design networks rather than implementing them.

That’s the reason why the CCDE was created. CCDEs create networks from nothing. Their coursework focuses on taking requirements and making a network out of it. That’s why their practical exam focuses less on command lines and more on product knowledge and implementation details. The CCDE is where people that build networks prove they know their trade.

The Road You Must Design For

When you look at the concepts behind SDN, it’s not really built for troubleshooting and implementation without thought. Yes, automation does help implementation. Orchestration helps new devices configure themselves on the fly. API access allows us to pull all kinds of useful information out of the network for the purposes of troubleshooting and management. But each and every one of these things is not in the domain of the CCIE.

Can SDN solve the thorny issues behind redistributing EIGRP into OSPF? How about creating Multiple Spanning Tree instances for odd numbered VLANs? Will SDN finally help me figure out how to implement Frame Relay Traffic Shaping without screwing up the QoS policies? The answer to almost every one of these questions is no.

SDNs major advantages can only be realized with forethought and guidelines. Orchestration and automation make sense when implemented in pods or with new greenfield deployments. Once they have been tested and proven, these concepts can be spread across the entire network and used to ease design woes.

Does it make more sense to start using Ansible and Jinja at the beginning? Or halfway through a deployment? Would you prefer to create Python scripts to poll against APIs after you’ve implemented a different network monitoring system (NMS)? Or would it make more sense to do it right from the start?

CCIEs may see SDN in practice as they start using things like APIC-EM to roll out polices in the network, but CCDEs are the real SDN gatekeepers. They alone can make the decisions to incorporate these ideas from the very beginning to leverage capabilities to ease deployment and make troubleshooting easier. Even though CCIEs won’t see SDN, they will reap the benefits from it being baked in to everything they do.


Tom’s Take

Rather than asking when the CCIE is going to get SDN-ified, a better question would be “Should the CCIE worry?” The answer, as explained above, is no. SDN isn’t something that a CCIE needs to study for. CCDEs, on the other hand, will be hugely impacted by SDN and it will make a big difference to them in the long run. Rather than forcing CCIEs into a niche role that they aren’t necessarily suited for, we should instead let them do what they do best. We should incorporate SDN concepts into the CCDE and let them do what they do best and make the network a better place for CCIEs. Everyone will be better in the long run.

Sorting Through SD-WAN

lightspeed

SD-WAN has finally arrived. We’re not longer talking about it in terms of whether or not it is a thing that’s going to happen, but a thing that will happen provided the budgets are right. But while the concept of SD-WAN is certain, one must start to wonder about what’s going to happen to the providers of SD-WAN services.

Any Which Way You Can

I’ve written a lot about SDN and SD-WAN. SD-WAN is the best example of how SDN should be marketed to people. Instead of talking about features like APIs, orchestration, and programmability, you need to focus on the right hook. Do you see a food processor by talking about how many attachments it has? Or do you sell a Swiss Army knife by talking about all the crazy screwdrivers it holds? Or do you simply boil it down to “This thing makes your life easier”?

The most successful companies have made the “easier” pitch the way forward. Throwing a kitchen sink at people doesn’t make them buy a whole kitchen. But showing them how easy and automated you can make installation and management will sell boxes by the truckload. You have to appeal the opposite nature that SD-WAN was created to solve. WANs are hard, SD-WANs make them easy.

But that only works if your SD-WAN solution is easy in the first place. The biggest, most obvious target is Cisco IWAN. I will be the first to argue that the reason that Cisco hasn’t captured the SD-WAN market is because IWAN isn’t SD-WAN. It’s a series of existing technologies that were brought together to try and make and SD-WAN competitor. IWAN has all the technical credibility of a laboratory full of parts of amazing machines. What it lacks is any kind of ability to tie all that together easily.

IWAN is a moving target. Which platform should I use? Do I need this software to make it run correctly? How do I do zero-touch deployments? Or traffic control? How do I plug a 4G/LTE modem into the router? The answers to each of these questions involves typing commands or buying additional software features. That’s not the way to attack the complexity of WANs. In fact, it feeds into that complexity even more.

Cisco needs to look at a true SD-WAN technology. That likely means acquisition. Sure, it’s going to be a huge pain to integrate an acquisition with other components like APIC-EM, but given the lead that other competitors have right now, it’s time for Cisco to come up with a solution that knocks the socks off their longtime customers. Or face the very real possibility of not having longtime customers any longer.

Every Which Way But Loose

The first-generation providers of SD-WAN bounced onto the scene to pick up the pieces from IWAN. Names like Viptela, VeloCloud, CloudGenix, Versa Networks, and more. But, aside from all managing to build roughly the same platform with very similar features, they’ve hit a might big wall. They need to start making money in order for these gambles to pay off. Some have customers. Others are managing the migration into other services, like catering their offerings toward service providers. Still others are ripe acquisition targets for companies that lack an SD-WAN strategy, like HPE or Dell. I expect to see some fallout from the first generation providers consolidating this year.

The second generation providers, like Riverbed and Silver Peak, all have something in common. They are building on a business they’ve already proven. It’s no coincidence that both Riverbed and Silver Peak are the most well-known names in WAN optimization. How well known? Even major Cisco partners will argue that they sell these two “best of breed” offerings over Cisco’s own WAAS solution. Riverbed and Silver Peak have a definite advantage because they have a lot of existing customers that rely on WAN optimization. That market alone is going to net them a significant number of customers over the next few years. They can easily sell SD-WAN as the perfect addition to make WAN optimization even easier.

The third category of SD-WAN providers is the late comers. I still can’t believe it, but I’ve been reading about providers that aren’t traditional companies trying to get into the space. Talk about being the ninth horse in an eight horse race. Honestly, at this point you’re better off plowing your investment money into something else, like Internet of Things or Virtual Reality. There’s precious little room among the existing first generation providers and the second generation stalwarts. At best, all you can hope for is a quick exit. At worst, your “novel” technology will be snapped up for pennies after you’re bankrupt and liquidating everything but the standing desks.


Tom’s Take

Why am I excited about the arrival of SD-WAN? Because now I can finally stop talking about it! In all seriousness, when the boardroom starts talking about things that means it’s past the point of being a hobby project and now has become a real debate. SD-WAN is going to change one of the most irritating aspects of networking technology for us. I can remember trying to study for my CCNP and cramming all the DSL and T1 knowledge a person could fit into a brain in my head. Now, it’s all point-and-click and done. IPSec VPNs, traffic analytics, and application identification are so easy it’s scary. That’s the power of SD-WAN to me. Easy to use and easy to extend. I think that the landscape of providers of SD-WAN technologies is going to look vastly different by the end of 2017. But SD-WAN is going to be here for the long haul.

Automating Your Job Away Isn’t Easy

programming

One of the most common complaints about SDN that comes from entry-level networking folks is that SDN is going to take their job away. People fear what SDN represents because it has the ability to replace their everyday tasks and put them out of a job. While this is nowhere close to reality, it’s a common enough argument that I hear it very often during Q&A sessions. How is it that SDN has the ability to ruin so many jobs? And how is it that we just now have found a way to do this?

Measure Twice

One of the biggest reasons that the automation portion of SDN has become so effective in today’s IT environment is that we can finally measure what it is that networks are supposed to be doing and how best to configure them. Think about the work that was done in the past to configure and troubleshoot networks. It’s often a very difficult task that involves a lot of intuition and guesswork. If you tried to explain to someone the best way to do things, you’d likely find yourself at a loss for words.

However, we’ve had boring, predictable standards for many years. Instead of cobbling together half-built networks and integrating them in the most obscene ways possible, we’ve instead worked toward planning and architecting things properly so they are built correctly from the ground up. No more guess work. No more last minute decisions that come back to haunt us years down the road. Those kinds of things are the basic building blocks for automation.

When something is built along the lines of predictable rules with proper adherence to standards, it’s something that can be understood by a non-human. Going all the way back to Basic Computing 101, the inputs of a system determine the outputs. More simply, Garbage In, Garbage Out. If your network configuration looks like a messy pile of barely operational commands it will only really work when a human can understand what’s going on. Machines don’t guess. They do exactly what they are told to do. Which means that they tend to break when the decisions aren’t clear.

Cut Once

When a system, script, or program can read inputs and make procedural decisions on those inputs, you can make some very powerful things happen. Provided, that is, that your chosen language is powerful enough to do those things. I’m reminded of a problem I worked on fifteen years ago during my internship at IBM. I needed to change the MTU size for a network adapter in the Windows 2000 registry. My programming language of choice wasn’t powerful enough for me to say something like, “Read these values into an array and change the last 2 or 3 to the following MTU”. So instead, I built a nested if statement that was about 15 levels deep to ensure I caught every possible permutation of the adapter binding order. It was messy. It was ugly. And it worked. But there was no way it would scale.

The most important thing to realize about SDN and automation is that we’ve moved past simply understanding basic values. We’ve finally graduated to a place where programs can make complex decisions based on a number of inputs. We’ve graduated from simple if-then-else constructs and up to a point where programs can take a number of inputs and make decisions based on them. Sure, in many cases the inputs are simple little things like tags or labels. But what we’re gaining is the ability to process more and more of those labels. We can create provisioning scripts that ensure that prod never talks to dev. We can automate turn-up of a new switch with multiple VLANs on different ports through the use of labels and object classes. We can even extrapolate this to a policy-based network language that we can use to build a task once and execute it over and over again on different hardware because we’re doing higher level processing instead of being hamstrung by specific device syntax.

Automation is going to cost some people their jobs. That’s a given. Just like every other manufacturing position, the menial tasks of assembling simple pieces or performing repetitive tasks can easily be accomplished by a machine or software construct. But writing those programs and working on those machines is a new kind of job in and of itself. A humorous anecdote from the auto industry says that the introduction of robots onto assembly lines caused many workers to complain and threaten to walk off the job. However, one worker picked up the manual for the robot and realized that he could easily start working on the it instead of the assembly line.


Tom’s Take

Automation isn’t a magic bullet to fix all your problems. It only works if things are ordered and structured in such a way that you can predictably repeat tasks over and over. And it’s not going to stop with one script or process. You need to continue to build, change, and extend your environment. Which means that your job of programming switches should now be looked at in light of building the programs that program switches. Does it mean that you need to forget the basics of networking? No, but it does mean that they way in which you think about them will change.