Can anybody explain what fault masking is, and and what its consequences are?
A:
From Wikipedia:
a way to ignore faults by seamlessly preparing a backup component to execute something as soon as the instruction is sent, using a sort of voting protocol where if the main and backups don't give the same results, the flawed output is ignored.
Imagine the five CPUs on the Space Shuttle, all crunching the same numbers. If one of them produces an anomalous result, that result is ignored. The other four CPUs "won the election" and "masked" (hid) the bad result.
Michael Petrotta
2010-09-24 05:43:30
Learned something new today.
Michael Petrotta
2010-09-24 05:43:39
I have a little knowledge about it...this is not i think is the right answer
Guri
2010-09-24 05:52:05
@Guri: well, Google in general disagrees with you. What do you think it means?
Michael Petrotta
2010-09-24 05:57:31
@Michael, Sir what you are talking about is fault tolerance not fault masking?
Guri
2010-09-24 06:12:55
@Guri: no, I don't think so. Fault tolerance might be the *tolerance* of errors, but fault masking is the *preparation* for the possibility of errors by preparing seamless backup.
Michael Petrotta
2010-09-24 06:17:59
@Michael:little bit i know about this is that it is error condition hiding another error condition...this is related to software testing
Guri
2010-09-24 06:30:28
@Guri: you probably should have said that. Meanings change based on context. You should edit your question with that context.
Michael Petrotta
2010-09-24 06:34:33
A:
Since you've tagged this as testing, this textbook definition might be what you're looking for
http://hissa.nist.gov/chissa/SEI_Framework/framework_17.html
An acceptance test successfully masks a bad value if a retry or alternate results in a new, correct result within the time limit set for declaring failure.
Also see some discussion here but the final answer is not too clear as an example
http://www.geekinterview.com/talk/7964-fault-masking-is.html
JoseK
2010-09-24 06:34:48