[SystemSafety] What do we know about software reliability?

[Derek M Jones]

Martyn,

> .... Bev's
> paper on "How reliable is a program that has never failed?" offers a
> useful rule-of-thumb: that aften n hours of fault free operation, there
> is about 50% chance of a failure in the following n hours (subject to
> some obvious constraints).

Is this the only (bit) useful theory paper from years past that has stood
the test of time?


> The difficulties rapidly escalate when you need 10^-4 or better at >90%
> confidence.
> 
> Martyn
> 
> On 14/09/2020 14:14, SPRIGGS, John J wrote:
>>
>> In my experience, if Software Reliability is mentioned at a
>> conference, at least one member of the audience will laugh, and if it
>> is mentioned in a work discussion, at least one member of the group
>> will get angry.
>>
>> Interestingly, some of the same people who say it is impossible to
>> quantify software failure rates will set numerical requirements for
>> Software Availability – if you get one of those, ask the Customer how
>> (s)he wants you to demonstrate satisfaction of the requirement.
>>
>>   
>>
>> John
>>
>> *From:*systemsafety
>> <systemsafety-bounces at lists.techfak.uni-bielefeld.de> *On Behalf Of
>> *Derek M Jones
>> *Sent:* 14 September 2020 12:54
>> *To:* systemsafety at lists.techfak.uni-bielefeld.de
>> *Subject:* [SystemSafety] What do we know about software reliability?
>>
>>   
>>
>> All,
>>
>> What do we know about software reliability?
>>
>> The answer appears to be, not a lot:
>> http://shape-of-code.coding-guidelines.com/2020/09/13/learning-useful-stuff-from-the-reliability-chapter-of-my-book/
>> <http://shape-of-code.coding-guidelines.com/2020/09/13/learning-useful-stuff-from-the-reliability-chapter-of-my-book>
>>
>> -- 
>> Derek M. Jones Evidence-based software engineering
>> tel: +44 (0)1252 520667 blog:shape-of-code.coding-guidelines.com
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-- 
Derek M. Jones           Evidence-based software engineering
tel: +44 (0)1252 520667  blog:shape-of-code.coding-guidelines.com