Technological Failures Biggest challenges are foreseeing a technologies impact before it is put into widespread use. Even if the problems are foreseen, humans may be unable to prevent failure of a technology if cultural and social issues get in the way (e.g. NASA culture and org. structure). Poorly designed interface of complex systems can lead to devastating accidents (e.g. cluttered control panels). For digital technology – complexity and security issues dominate concerns Denial of service attacks, power grid dependability Bug fixing is never 100% PhD in math can prove correctness of 10 lines of code/day Cyber attacks – cyberwar Media “spin” affects cultural public opinion Hindenburg, shuttle, nuclear power, etc. Ice fall off was normal on shuttle, bugs normal in testing with abnormal data but ignored in production X-ray SW, denial of service attack ITEC 102

Bugs in software Verify and validate Testing is expensive Testing is never done Users can do things never considered by developers codecs ITEC 102