Icarus The Network Engineer

I don’t remember the movie. A character is afraid of flying. Even after his fellow passengers explain the science behind the Bernoulli effect and jet engines, he’s not convinced.

If the gods struck down Icarus for flying too close to the sun, imagine what they will so when this monstrosity roars through the skies.

The theory behind flight is well understood. And yet, who can look at a 200 ton 747 jumbo jet without questioning the science. . .at least a little.

My son-in-law is a professional airline pilot. He’s logged thousands of hours in everything from a single engine Cessna to a multi-engine passenger jet. And yet, I still have trouble believing he can lift thousands of pounds of aircraft off terra firma and deposit it again safely thousands of miles away.

I’m a computer expert. I’m not bragging when I say that. It’s just what I’ve been trained in. I have more certifications than I can remember. I’ve helped write software certification exams. I’ve written computer books and magazine articles.

There was a time when “the computer guy” knew pretty much everything there was to know about computers. Those days are long gone. But, I do know networks and how computers talk to each other. I’ve written training courses on how networks communicate.

And yet, like the cobbler’s poor children, my home network often has been a mess. I finally decided I was going to clean it up. I ran some network cable to my new office. I installed jacks and computer “plugs” called RJ-45 connectors. I’ve had multiple WIFI networks for the past year. And then I broke one a few months ago.

So, I set out to “fix” my home network. As I moved devices around (computers, TVs, gaming consoles, cameras,) at times stuff didn’t work that should have. And other times stuff did work when it shouldn’t have.

They say that when a scuba diver gets disoriented underwater they need to “follow the bubbles.” It’s possible to confuse up for down when swimming under water without a fixed reference point. But, bubbles ALWAYS go up. So, even if you believe “up” is one direction, if the bubbles are going the other way, you have to trust the bubbles.

Living in Utah, avalanches are a danger. The advice to avalanche victims is similar to scuba divers. But, instead of bubbles going up, spit goes down. If you can create a breathing hole during the avalanche let some spit dribble out of your mouth. The spit will ALWAYS go down. So, start digging in the opposite direction. (Oh, and take an avalanche beacon. Doesn’t fit my example, but it’s the best way to prepare for an avalanche.)

When computer networks, the same principle applies. If you design the network properly, especially if you are changing an existing configuration, you have to trust that all the pieces will do what they are supposed to do.

It’s like Novocaine. Just give it time, it always works

– Coach Herman Boone Remember The Titans

When a computer, or any device, joins a network, the device will go out and ask for the correct configuration information; IP Address, IP Mask, DNS server, default gateway.

The information is provided by something called the DHCP server. And the information is called a lease. The lease has an expiration date and time. The thing the device sometimes won’t go look for a new DHCP lease until the old one expires. So, you can set a network up correctly, and when you first attach the devices they won’t be able to communicate or get to the internet. But, if you’ve done it correctly eventually it will work. . .just like Novocaine.

And yet, despite understanding everything I just said, I’m still surprised when I build a network and everything works. Especially if I had to redesign a broken system.

I feel like Icharus just waiting for the wax to melt.

It helps to draw a network map

Stay safe

Rodney M Bliss is an author, columnist and IT Consultant. His blog updates every weekday. He lives in Pleasant Grove, UT with his lovely wife, thirteen children and grandchildren.

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