'I Wonder What This Cable Does': How To Tell Thicknet From A Thickhead

On Call Is a Loose Cannon worse than a Big Cheese? What happens when the two are combined? Stir in some overconfidence and you have today's entry in the On Call archives.

Our tale today comes from a reader Regomized as "Jon", who was working for a small software development company in Cupertino, California (no, not that one.) One of the company's customers was a large corporation (also not that one) and the principal contact was their Director of Engineering "who was ... let's say a bit of a loose cannon," said a diplomatic Jon.

"This individual would show up to talk to our management, toting a Compaq luggable, and we'd put him into a conference room to wait while we gathered the requested people. And with remarkable frequency, shortly afterward, the network would go down."

Frantic calls were made. Users scrambled for connectivity. But the connection (pun not intended) was not made until the fourth time the network toppled over and the root cause was discovered.

First, a little bit of background on Jon's network. The backbone was thicknet, and off it sprung thinnet extensions. The thicknet backbone terminated in the very conference room where our friend, the Loose Cannon, was deposited. The terminator on the end of cable was just one of the critical parts of the network and, if missing, would mean some pretty severe communication disruption.

You can probably see where this is going.

The Loose Cannon's luggable sported a thinnet Ethernet card. And there was the end of the thicknet backbone, with a connector that looked for all the world like it would make a good fit and introduce the luggable to the network.

"Once he'd noticed this fact, being somewhat short on precise knowledge of how thinnet worked and also, as mentioned, a Loose Cannon, he would just pop the terminator off the end of the thinnet and plug it directly onto his network card without a T."

Naturally, no permission was requested. There was a cable. A handy connector. He was sat alone. What could go wrong?

The network would immediately crash, but for our Loose Cannon it simply looked like he couldn't connect to anything. Nothing ventured, nothing gained, he'd simply unplug his Compaq, put the terminator back on and carry on as though nothing had happened.

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Three times he did this, unleashing all manner of mayhem outside the conference room. But for him, it was simply duff connectivity. Or perhaps some really good security. Either way, Compaq's heftiest and finest remained resolutely offline.

The fourth time, however, he was caught in the act. Either by someone turning up with beverages and cookies as cables were connected or support staff that had developed a nervous tic when the something-bad-has-happened pager went off.

Sadly, the education that was dispensed is lost to the mists of time.

"Words," said Jon, "were said."

Ever been faced with a seemingly insoluble networking problem, only to find the solution sitting in a conference room, eating cookies? Or were you the person that triggered the pagers with an innocent "I wonder what this cable does?" Tell all with an email to On Call. ®