Growing up, I heard this one a lot.

Someone would point at two kids and say this one is book smart and that one is street smart. It was never a compliment to both. Book smart meant good grades and nothing else. Street smart was the kid who barely passed, always had money, and could fix anything. Nobody called him smart in a classroom. Outside the classroom, everybody did.

So you could finish top of the class and still be told you did not understand anything real. The label was never about intelligence. It was about which room you were standing in. But it wasn’t really about intelligence itself, that is a whole other topic. Book smart and street smart are not two types of people. They are two halves of one skill, and most of us start with only one of them.

Book smart is knowing why something works. Street smart is knowing what usually happens. One is a model in your head. The other is pattern recognition you earned by being wrong many times.

#Then I became a network engineer and since life is nothing but a big game of spotting patterns, I managed to apply this to my job (because I love my job) On paper, a network is a beautiful thing. Clean diagram. Protocols that behave exactly like the book says. Every device answers when you talk to it.

In real life:

  • The diagram is two years old.
  • The documented VLAN does not exist.
  • The client swears nothing changed.

Book smart taught me why an IPsec tunnel needs NAT-T. It taught me what happens to the packet, why the port changes, why the peer stops recognizing it.

Street smart taught me the tunnel is down because someone rebooted a firewall on a Friday evening and went home. Book smart taught me the theory of SIP. Signaling here, media there, this codec, that timer.

Street smart taught me that “the phones are cutting out” is never really about the phones. It is the link. It is always the link. Book smart gives you one command that does one job. Street smart is knowing that IOS-XE, VRP and OneOS all want that command written a different way, and the one you memorized is the one that will not work tonight.

What happens when you only have one⌗

I have seen both failures.

Skip the books and you become the engineer who reboots things until they work (You memorize but you don’t understand). You will close the ticket. You will look fast. But you never fixed the problem, you just moved it, and it will come back on a day you are not on call. Skip the field and you become the engineer who can explain the OSI model perfectly while the client is still offline. Your explanation is correct. It is also useless right now.

Both of these people believe they are good at their job. I believe that both are half an engineer.

How you get both⌗

In the spirit of self-criticism, this where I am : A not so bad mix of both. I spend my time studying the theory of how things work, till the day I get to apply it in real life. But you cannot wait for experience to arrive. And Nobody hands a junior a broken production network and says go ahead.

So you build one. You study a topic until you understand why it works. Then you build it in a lab and break it on purpose. You unplug things. You misconfigure things. You watch what the failure actually looks like from the other side, because that is the view you will get in real life. You will never get a ticket that says “STP is blocking the wrong port.” You will get a ticket that says “the internet is slow.” That is the whole trick. Theory tells you where to look. Experience tells you where to look first.

Study hard. Then go break things. Then go fix those things.

Do that long enough and nobody has to pick a label for you.