1 / 33

BUGS and FAULTS

Explore various software bugs and faults, including syntax errors, human mistakes, wrong diagnostics, and their real-world consequences. Learn from past incidents to avoid future mishaps.

clementd
Download Presentation

BUGS and FAULTS

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript


  1. BUGS and FAULTS

  2. Mercury software bug • Syntax error in software • DO I=1.10 .... DO I=1,10 • 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 => 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 didn’t 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.

More Related