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Habits of Network Experts

For any field of study, there are some mental habits that will make you an expert over time. Whether you are an infrastructure architect, a network designer, or a network reliability engineer, what are the habits of mind those involved in the building and operation of networks follow that mark out expertise?

Experts involve the user

Experts don’t just listen to the user, they involve the user. This means taking the time to teach the developer or application owner how their applications interact with the network, showing them how their applications either simplify or complicate the network, and the impact of these decisions on the overall network.

Experts think about data

Rather than applications. What does the data look like? How does the business use the data? Where does the data need to be, when does it need to be there, how often does it need to go, and what is the cost of moving it? What might be in the data that can be harmful? How can I protect the data while at rest and in flight?

Experts think in modules, surfaces, and protocols

Devices and configurations can, and should, change over time. The way a problem is broken up into modules and the interaction surfaces (interfaces) between those modules can be permanent. Choosing the wrong protocol means choosing a different protocol to solve every problem, leading to accretion of complexity, ossification, and ultimately brittleness. Break the problem up right the first time, and choose the protocols carefully, and let the devices and configurations follow.

Choosing devices first is like selecting the hammer you’re going to use to build a house, and then selecting the design and materials used in the house based on what you can use the hammer for.

Experts think about tradeoffs

State, optimization, and surface is an ironclad tradeoff. If you increase state, you increase complexity while also increasing optimization. If you increase surfaces through abstraction, you are both increasing and decreasing state, which has an impact both on complexity and optimization. All nontrivial abstractions leak. Every time you move data you are facing the speed of serialization, queueing, and light, and hence you are dealing with the choice between consistency, availablity, and partitioning.

If you haven’t found the tradeoffs, you haven’t looked hard enough.

Experts focus on the essence

Every problem has an essential core—something you are trying to solve, and a reason for solving it. Experts know how to divide between the essential and the nonessential. Experts think about what they are not designing, and what they are not trying to accomplish, as well as what they are. This doesn’t mean the rest isn’t there, it just means it’s not quite in focus all the time.

Experts are mentally stimulated to simulate

Labs are great—but moving beyond the lab and thinking about how the system works as a whole is better. Experts mentally simulate how the data moves, how the network converges, how attackers might try to break in, and other things besides.

Experts look around

Interior designers go to famous spaces to see how others have designed before them. Building designers walk through cities and famous buildings to see how others have designed before them. The more you know about how others have designed, the more you know about the history of networks, the more of an expert you will be.

Experts reshape the problem space

Experts are unafraid to think about the problem in a different way, to say “no,” and to try solutions that have not been tried before. Best common practice is a place to start, not a final arbiter of all that is good and true. Experts do not fall to the “is/ought” fallacy.

Experts treat problems as opportunities

Whether the problem is a mistake or a failure, or even a little bit of both, every problem is an opportunity to learn how the system works, and how networks work in general.


Is it planning… or just plain engineering?

Over at the ECI blog, Jonathan Homa has a nice article about the importance of network planning–

In the classic movie, The Graduate (1967), the protagonist is advised on career choices, “In one word – plastics.” If you were asked by a young person today, graduating with an engineering or similar degree about a career choice in telecommunications, would you think of responding, “network planning”? Well, probably not.

Jonathan describes why this is so–traffic is constantly increasing, and the choice of tools we have to support the traffic loads of today and tomorrow can be classified in two ways: slim and none (as I remember a weather forecaster saying when I “wore a younger man’s shoes”). The problem, however, is not just tools. The network is increasingly seen as a commodity, “pure bandwidth that should be replaceable like memory,” made up of entirely interchangeable parts and pieces, primarily driven by the cost to move a bit across a given distance.

This situation is driving several different reactions in the network engineering world, none of which are really healthy. There is a sense of resignation among people who work on networks. If commodities are driven by price, then the entire life of a network operator or engineer is driven by speed, and speed alone. All that matters is how you can build ever larger networks with ever fewer people–so long as you get the bandwidth you need, nothing else matters.

This is compounded by a simple reality–network world has driven itself into the corner of focusing on the appliance–the entire network is appliances running customized software, with little thought about the entire system. Regardless of whether this is because of the way we educate engineers through our college programs and our certifications, this is the reality on the ground level of network engineering. When your skill set is primarily built around configuring and managing appliances, and the world is increasingly making those appliances into commodities, you find yourself in a rather depressing place.

Further, there is a belief that there is no more real innovation to be had–the end of the road is nigh, and things are going to look pretty much like they look right now for the rest of … well, forever.

I want you, as a network engineer, operator, or whatever you call yourself, to look these beliefs in the eye and call them what they are: nonsense on stilts.

The real situation is this: the current “networking industry,” such as it is, has backed itself into a corner. The emphasis on planning Jonathan brings out is valid, but it is just the tip of the proverbial iceberg. There is a hint in this direction in Jonathan’s article in the list of suggestions (or requirements). Thinking across layers, thinking about failure, continuous optimization… these are all… system level thinking, To put this another way, a railway boxcar might be a commodity, but the railroad system is not. The individual over-the-road truck might be a commodity, and the individual road might not be all that remarkable, but the road system is definitely not a commodity.

The sooner we start thinking outside the appliance as network engineers or operators (or whatever you call yourself), the sooner we will start adding value to the business. This means thinking about algorithms, protocols, and systems–all that “theory stuff” we typically decry as being less than usefl–rather than how to configure x on device y. This means thinking about security across the network, rather than as how you configure a firewall. This means thinking about the tradeoffs with implementing security, including what systemic risk looks like, and when the risks are acceptable when trying to accomplish as specific goal, rather than thinking about how to route traffic through a firewall.

If demand is growing, why is the networking world such a depressing place right now? Why do I see lots of people saying things like “there will be no network engineers in enterprises in five years?” Rather than blaming the world, maybe we should start looking at how we are trying to solve the problems in front of us.

The End of Specialization?

There is a rule in sports and music about practice—the 10,000 hour rule—which says that if you want to be an expert on something, you need ten thousand hours of intentional practice. The corollary to this rule is: if you want to be really good at something, specialize. In colloquial language, you cannot be both a jack of all trades and a master of one.

Translating this to the network engineering world, we might say something like: it takes 10,000 hours to really know the full range of products from vendor x and how to use them. Or perhaps: only after you have spent 10,000 hours of intentional study and practice in building data center networks will you know how to build these things. We might respond to this challenge by focusing our studies and time in one specific area, gaining one series of certifications, learning one vendor’s gear, or learning one specific kind of work (such as design or troubleshooting).

This line of thinking, however, should immediately raise two questions. First, is it true? Anecdotal evidence seems to abound for this kind of thinking; we have all heard of the child prodigy who spent their entire lives focusing on a single sport. We also all know of people who have “paper skills” instead of “real skills;” the reason we often attribute to this is they have not done enough lab work, or they have not put in hours configuring, troubleshooting, or working on the piece of gear in question. Second, is it healthy for the person or the organization the person works for?

To make matters worse, we often see this show p in the job hunting process. The manager wants someone who can “hit the ground running” on this project, using this piece of equipment, and they want them on board and working tomorrow. In response, we see job descriptions and recruiting drives for specific skill sets, down to individual hardware and software.

I recently ran across two articles that push back on this 10,000 hours10,000 rule way of learning does not work.

Over time, as I delved further into studies about learning and specialisation, I came across more and more evidence that it takes time to develop personal and professional range – and that there are benefits to doing so. I discovered research showing that highly credentialed experts can become so narrow-minded that they actually get worse with experience, even while becoming more confident (a dangerous combination). And I was stunned when cognitive psychologists I spoke with led me to an enormous and too-often ignored body of work demonstrating that learning itself is best done slowly to accumulate lasting knowledge, even when that means performing poorly on tests of immediate progress. That is, the most effective learning looks inefficient – it looks like falling behind.

Re-read that last sentence—what turns out to be the most effective learning strategy often looks just like falling behind. Another recent article pointed out that deep expertise seems to be losing its sway in many workplaces. The author spends time around a new United States Navy littoral ship, which are designed to operate with much smaller crews—one-half to one-third of a comparably sized ship staffed in the traditional way. How do these ships operate? By cross training crew members to be able to do many different tasks.

One of the interesting things this latter article points out is this ability to do many different tasks requires fluid intelligence, which is a completely different set of skills than crystallized intelligence. Fluid intelligence, it seems, becomes stronger over time, peaking much later in life. While the article does not discuss how to develop the kind of fluid intelligence that will serve you well later in life, when this kind of thinking overtakes your narrower skill sets, it makes sense that building a broader set of skills over time is a more likely path than following the 10,000 hour rule.

There is, however, one question that neither author spends a lot of time discussing: if you are not focusing on learning one thing, then how, and on what, should you focus your time spent learning on? For the top athletes in the sports article, it seems like they spent a lot of time in different kinds of physical activity. There was an area of focus, but it was not the kind of narrow focus we normally associate with being excellent at one sport. In the same way, the sailors in the second article were all focused in a broader area—anything required to run a ship. Again, there is focus, but not the kind of narrow focus you might have expect on more standard boats, where one set of sailors just focus on working the lines, while another just focus on navigating, etc. The focus is still there, then—it is just a broader focus.

Why and how does this work? My guess is it works because the skills you learn in dancing, for instance, will help you learn better footwork in boxing and other sports (an example given in the sports article linked above). The skill you learn in handling the lines will help you understand the lay and movement of the boat in ways that are helpful in navigation. These skills, in other words, are somewhat adjacent.

But these skills are more than adjacent. Many of them are also basic, or theoretical, in ways we do not value in the network engineering world. The point I often hear made is: I don’t care about how BGP really works, so long as I can write a script that configures it, and I can troubleshoot it when it breaks. Or: I actually work on vendor x model 1234 all day, what I really need to know to be effective is how to configure it… when I need to replace that piece of gear, I will learn the next one so I can keep doing my job.

My point is this: this way of building skills, this way of working, does not “work” in the long term. There will come a point in your life, and in the life of your company, when point skills will weaken and lose their importance. The research, and experience, shows the better way to learn is to take on the long game, to learn the theory, and to practice the theory in many different settings, rather than focusing too deeply on one thing.

Reaction: Overly Attached

In a recent edition of ACM Queue, Kate Matsudaira has an article discussing the problem of being overly attached to a project or solution.

The longer you work on one system or application, the deeper the attachment. For years you have been investing in it—adding new features, updating functionality, fixing bugs and corner cases, polishing, and refactoring. If the product serves a need, you likely reap satisfaction for a job well done (and maybe you even received some raises or promotions as a result of your great work).

Attachment is a two-edged sword—without some form of attachment, it seems there is no way to have pride in your work. On the other hand, attachment leads to poorly designed solutions. For instance, we all know the hyper-certified person who knows every in and out of a particular vendor’s solution, and hence solves every problem in terms of that vendor’s products. Or the person who knows a particular network automation system and, as a result, solves every problem through automation.

The most pernicious forms of attachment in the network engineering world are to a single technology or vendor. One of the cycles I have seen play out many times across the last 30 years is: a new idea is invented; this new idea is applied to every possible problem anyone has ever faced in designing or operating a network; the  resulting solution becomes overburdened and complicated; people complain about the complexity of the solution and rush to… the next new idea. I could name tens or hundreds of technologies that have been through this cycle over time.

Another related cycle: a team adopts a new technology in order to solve a problem.

Kate points out some very helpful ways to solve over-attachment at an organizational level. For instance, aligning on goals and purpose, and asking everyone to be open to ideas and alternatives. But these organizational level solutions are more difficult to apply at an individual level. How can this be applied to the individual—to your life?

Perhaps the most important piece of advice Kate gives here is ask for stories, not solutions. In telling stories you are not eliminating attachment but refocusing it. Rather than becoming attached to a solution or technology, you are becoming attached to a goal or a narrative. This accepts that you will always be attached to something—in fact, that it is ultimately healthy to be attached to something outside yourself in a fundamental way. The life that is attached to nothing is ugly and self-centered, ultimately failing to accomplish anything.

Even here, however, there are tradeoffs. You can attach yourself to the story of a company, dedicating yourself to that single brand. To expand this a little, then, you should focus on stories about solving problems for people rather than stories about a product or technology. This might mean telling people they are wrong, by the way—sometimes the best thing is not what someone thinks they want.

Stories are ultimately about people. This is something not many people in engineering fields like to hear, because most of us are in these kinds of fields because we are either introverted, or because we struggle to relate to people in some other way.

To expand this a bit more, you should be willing to tell multiple stories, rather than just one. These stories might overlap or intersect, of course—I have been invested in a story about reducing complexity, disaggregation, and understanding why rather than how for the last ten or fifteen years. These three stories are, in many ways, the same story, just told from different perspectives. You need to allow the story to be shaped, and the path to tell that story to change, over time.

Realize your work is neither as bad as you think it is, nor as good as you think it is. Do not take criticism personally. This is a lesson I had to learn the hard way, from receiving many manuscripts back covered in red marks, either physical or virtual. Failure is not an option; it is a requirement. The more you fail, the more you will actively seek out the tradeoffs, and approach problems and people with humility.

Finally, you need to internalize modularity. Do not try to solve all the problems with a single solution, no matter how neat or new. Part of this is going to go back to understanding why things work the way they do and the limits of people (including yourself!). Solve problems incrementally and set limits on what you will try to do with any single technology.

Ultimately, refusing to become overly attached is a matter of attitude. It is something that is learned through hard work, a skill developed across time.

Mentorship and Early Career Development

In this episode of the Network Collective, John Fraizer, Denise Fishburn, and Trey Aspelund join the NC crew to talk about the importance of mentorship and practical advice on how to mentor and be mentored.

Outro Music:
Danger Storm Kevin MacLeod (
Licensed under Creative Commons: By Attribution 3.0 License

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