BUGS and FAULTS

1
BUGS and FAULTS
2
Mercury software bug

• Syntax error in software
• DO I1.10 .... DO I1,10
• Luckily the software mistake was detected before
  the moon flights.

3
Ariane 5

• Missile failure.
• The launcher veered off its flight path broke up
  and exploded.
• The incident occured 37 seconds after the launch.

4
Human mistakes

• Falklands war. February 10 83.
• The Exocet sank the sheffield boat.
• Missing report of an incoming missile
• Satellite phone was used at the time so the radar
  could not be used

5
Wrong diagnostics

• 99 years old man.
• Highly abnormal white blood cell count.
• The computer reported of a normal white blood
  cells count.
• The computer reported values for an infant child.
• The prefix 19 was ignored by the computer (1889
  gt 1989).

6
Bad facilities

• UK 1982.
• 1000 cancer patients were given radiation doses
  10-30 less than required for a period of 10
  years
• Unnecessary correction factor was entered by the
  system administrator.

7
Medical DataBase mistakes

• Germany 1987
• A woman got wrong information about incurable
  syphilis she had passed to her children.
• She murdered both children and tried to kill her
  self.

8
Emergency problems

• 1989 Sun-Francisco - A death of a 5 years old
  child.
• The system truncated the last digit in his street
  number.
• The ambulance didnt arrive on time.

9
Billing and Skewing

• Electrifying bills
• A Tampa couple was build 4,062,599,57 (monthly
  payment)
• The original bill 146,76
• Water bills
• Water bill for 22,000 (one million gallons)
• Mistake in the replacement of the meter

10
IRS Over billing

• September 1990 Texas
• Woman was billed 67,000
• After a year she received a 1 billion bill
• Accurate calculation of interest

11
Jail Security

• Computer sets prisoners free
• Los Angeles Jail August 25 1987
• Jailed Cocaine dealer freed by email.
• Access to the jail computer system.
• Santa Fe jail computer system control of
  security was down (7 prisoners escaped)

12
Computer New Justice

• Dutch computer system sets criminals free and
  arrests innocent people.
• San Joaquin County jail doors were unlocked.
• A release of 120 dangerous inmates.
• Computer system jailed jailers for 10 hours and
  released few prisoners due to a 5 minute
  outage(Oklahoma jail).

13
The lottery

• Autonomic computer
• Let users fill the numbers beyond the time
  permitted
• 6 man won the lottery price

14
Computing errors

• Fortran in German
• In German Device Unit are the same word
• writing to unit 6 gives standard output
• Writing to device 6 overwrites the disk.

15
Accidental financial losses

• The Bank Of NY had 32 billion dollars overdraft.
• Overflow of a 16 bit counter was not checked .
• Self borrowing of 24 billion dollars to cover
  itself.
• self payments of 5 million dollars interest per
  day.

16
Hi-tech theater controls

• The rotating stage for the American premiere of
  Les Miserable failed
• the turntable could be operated only at full
  speed, which was much too fast to be safe
• The Amsterdam Opera had installed a modern
  computer-controlled door system.
  Unfortunately, the doors did not work properly,
  and people were locked inside.

17
Ambient Interference

• Interference from electronic or other signals is
• a nasty problem because it is difficult to
• prevent and is difficult to diagnose when it
• does occur.

18
Garage doors for openers

• Years ago, signals from Sputnik, the first
• Soviet orbiter, opened and closed garage
• doors as it went overhead.

19
Automobile microprocessor interference

• There have been numerous reports on
• microprocessor-controlled automobile control
• systems being sensitive to electromagnetic
• interference, particularly from nearby
• citizen's-band transmitters. Effects have
• included the sudden speeding up of cars on
• automatic cruise control.

20
Particle Escalator and Fishing

• The calculation of a huge particle escalator in
  the states did not agree with measurments
• A programmer noticed that the problem where
  especially bad when his father goes fishing
• The solution?

21
Spelling correctors often suggest inappropriate
corrections.

• Spelling checker for a Unix system failed to
  recognize the word Unix
• Microsoft Word failed to recognize Microsoft word.

22
Yes, But I'm Not Dead!

• Computer databases have created the
• mistaken impression that someone was dead,
• with various consequences.

23
Checks bounced

• Forman Brown wrote in
• the Los Angeles Times that his bank was
• rejecting his checks with a deceased stamp,
• the Social Security Administration had
• stopped depositing checks into his account,
• and Medicare objected to paying bills 6
• months after his alleged death. His death had
• been erroneously recorded.

24
Refund blocked

• Judi Sommer in Vancouver (at 40 years of
• age) was prevented from receiving a tax
• refund from Revenue Canada, which
• insisted she was dead. Her social insurance
• number had been inadvertently reported,
• instead of her deceased mother's.

25
But what if you really are dead?

• The death of a reclusive 51-year-old Dutch
  man was masked for 6 months because all of his
  bills were being paid automatically.
• The 1990 death of an elderly Swedish woman
  went unnoticed for 3 years for the same reason.

26
Beware of name similarities

• Donny Ray Boone spent 41 days in jail in Florida
  because of a confusion with a similarly named
  individual .
• Two people named Shirley Jones had different
  birthdays, heights (6 inches apart) and weights
  (70 pounds apart). The wrong one was arrested
  despite the obvious disparities, while the real
  suspect was already in jail .

27
Name-and-Address Problems

• Mail addressed to SWITZERLAND was routed to a
  nonexistent town in North Dakota, Switzerla ND.
• Mail to WEST GERMANY was sent to West Germa NY.
• Mail to DEUTSCHLAND was sent to DEUTSCHLA ND

28
ToysRUs
29
ToysRUs Disasters (1999-2000)

• 2M (14) net loss due to performance problems
• 4M spent to increase performance
• 1.5M in civil penalties for Federal mail-order
  rule violations with late merchandise shipping
  (missed promised Christmas deliveries)
• 9M (75) net loss due to decline in on-line sales

30
eBay
31
eBay Disaster (1999)

• 21 hour outage.
• 5M net loss.
• 11 drop in share price.
• 1.2M daily website visitors lost bids.
• Outage occurred as eBay was readying itself for
  an open house for Wall Street analysts.

32
Victoria's Secret
33
Victoria's Secret Disaster (1999)

• Annual Spring Fashion show on the internet
  crashed as millions of viewers tried to log on.
• Advertised during Super Bowl XXXIII to attract
  the maximum number of customers.
• Super Bowl XXXIII advertisement cost 1.6M for 30
  seconds worth of air time.
• The computers were configured to handle from 250K
  to 500K simultaneous viewers. The web site went
  down as 5M viewers tried to log on.
• The first large-scale live video event attempted
  on the internet.