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When computers go wrong

When computers go wrong

Posted on 10 Dec 2010 at 15:18

Stewart Mitchell charts the world's ten most calamitous computer cock-ups

When computers go wrong, they often go spectacularly wrong.

In most cases, catastrophic failures are blamed on “computer bugs”, although human error is normally the root cause for embarrassing failures.

No-one really knows where the term “bug” comes from. Some say it dates back to Thomas Edison’s pioneering work in the 19th century; others claim it refers to a moth that was evicted from the computer of one Grace Murray Hopper at Harvard University in 1947. What we do know is that bugs can make a mess of the best-laid plans.

Here, we look at ten IT disasters that highlight the precariously fickle nature of computers. Although our top ten mistakes may have caused lasting damage to the finances or reputations of those involved, nobody was physically harmed in the making of this list.

Gas pipe piracy

By the early 1980s, the Soviet Union was searching for better technology for its industrial control systems, and the simplest and cheapest way to develop state-of-the-art software was by pinching it from the West. This, however, was to prove a costly mistake.

The USA – deeply troubled by the emergence of Russia’s gas pipelines as a major economic beating stick to wield over Europe – learned of the Soviets’ intentions to steal software, and thought the opportunity of giving them bogus code was too good to pass up.

In a classic piece of espionage that would earn a standing ovation from John Le Carré, the CIA uncovered a KGB operation to harvest technical details and set up a counter-intelligence sting

In a classic piece of espionage that would earn a standing ovation from John Le Carré, the CIA uncovered a KGB operation to harvest technical details and set up a counter-intelligence sting.

Working on a tip-off from a French connection who had defected from Russia, US agents planted a specially modified version of the pipeline software at the Canadian company the KGB was targeting.

The time bombs in the software were so cunningly hidden that the code passed Russian inspection and went into the master control system for a pipeline designed to carry over 40 billion cubic metres of gas a year to Europe.

The software wreaked havoc with the pipes. As valves, pumps and turbines turned on and off at random, internal pressure reached bursting point, rupturing the pipe and causing an explosion that could be seen from space. Remarkably, no-one was hurt, but the tactic was the sort of copyright protection the record industry would kill for.

Pentium flunks long division

Q: What do you get when you cross a Pentium PC with a research grant?

A: A mad scientist.

This is just one of the science community’s in-jokes after a glitch in Intel’s Pentium processors meant they spat out incorrect answers to calculations.

Intel had been promoting Pentium chips heavily in the early summer of 1994. Professor Thomas Nicely was using one of the early models to run a program that generated prime numbers, and their twin, triplet and quadruplet prime relatives.

Taxing work at the best of times, but actually impossible if your calculator is on the blink.

Nicely noticed anomalies in the results of his research, but it took him five months to trace the problem, and he was understandably catatonic to learn that the mistake came from his state-of-the-art processor.

Unlike previous CPUs from Intel, the 486DX and Pentiums included a floating-point unit (FPU) – also known as a maths co-processor – that was used for calculating maths problems using floating-point numbers (numbers too large to be represented as integers).

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User comments

Has history changed?

I recall reading that the primary cause of the August 2003 blackout was that the MS based monitoring systems were down due to a virus. Is Microsoft rewriting history?

By MashedPotatoes on 12 Dec 2010

Regarding Oko...

It's a shame no mention was made of the "Able Archer 83" NATO exercise (simulating everything leading up to a nuclear strike, and conducted barely a month after) since the Soviets thought it was the real deal.

By Pyrion on 12 Dec 2010

Re: MashedPotatoes

No, the article is correct. The blackout was caused, in large part, due to a race condition bug in GE's XA/21 SCADA system, which has since been corrected. The bug was uncovered after two months of extensive code reviews by GE.

By dvalle686 on 12 Dec 2010


By DeadlyNinja on 12 Dec 2010

Admiral Grace Hopper

The reference to 'one Grace Murray Hopper' implies that Grace Hopper was a nobody. She was, in fact, one of the greatest pioneers of the early days of computing.

Please correct this reference to show the proper respect!

By rreiner on 12 Dec 2010

But if it wasn't for the MS Blaster worm...

The MS based PCs monitoring the grid that were infected with Blaster would have alerted operators to the problem and given them a chance to react.

By MashedPotatoes on 13 Dec 2010

Cost of 1990 AT&T network outage

AT&T $60 mil lost revenue (alleged) This is perhaps an arguable figure, but we'll accept it.

What was unacceptable and likely cost much more over time was the expense of a nationwide witchhunt, involving 2 USG agencies and prosecutors all over the country, to blame innocent hackers and BBS sysops for AT&T's cock-up.

AT&T even summarily shut down, an AT&T 3b2 based Unix BBS one of it's employees had set up on an unused system
in the Dallas Trade Mart. The sysop had made the mistake of passing along to corporate security a copy of the notorious E911 documents which had showed up on the system.

Just goes to show you no good deed goes unpunished when it comes to suits. Bonus points if you remember the sysop's name.

By jbdigriz on 13 Dec 2010

Re: Admiral Grace Hopper

I read the article differently it seems, since it implied Grace Hopper was so famous that she needed no further introduction. Which sounds right to me.

By pheasnt on 13 Dec 2010

@ MashedPotatoes

No, no and no. Just plain no. No idea what your agenda is (I can guess, though) but the NERC report after the investigation into the blackout specifically states it was nothing to do with Blaster - people merely drew that conclusion because the virus was so prevalent around that time.

It was all down to the bug in the XA/21 system - that's it.

By bioreit on 15 Dec 2010

IT links to blackout under scrutiny

"On January 25, 2003, Davis-Besse nuclear power plant was infected
with the MS SQL Server 2000 worm. The infection caused data overload
in the site network, resulting in the inability of the computers to
communicate with each other."

By doperative on 16 Dec 2010

other failed software projects

Lets not forget the London Ambulance fiasco

See also Sabina SEIFERT's Project

By doperative on 16 Dec 2010

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