Sunday, August 19, 2012

Difference between Fault and Failure

Difference between Fault and Failure

Source Fault Failure
StackExchange Fault is a software defect (incorrect step, process or data definition) that causes a failure. The inability of a software to perform its required functions within specified performance requirements.
Testing Standards A manifestation of an error in software. A fault, if encountered may cause a failure. Deviation of the software from its expected delivery or service.
Identifying Relevant Information for Testing Technique Selection: By Sira Vegas, Natalia Juristo, Victor R. Basili An error becomes a fault when it is written (included) in any of the developed software products. Failures occur when a software system does not behave as desired (does not do what it should do), which reveals a fault in the software.
StackOverflow A fault is the cause of an error. A software fault lies in software, a hardware fault lies in hardware A failure occurs when the observed behaviour differs from the expected one. Note that the reference is the expected behaviour, not the specification, since even the spec could be false.
FDA An incorrect step, process, or data definition in a computer program. The inability of a system or component to perform its required functions within specified performance requirements. It is manifested as a fault.

Another good differentiation between fault & failure [Rob Davis]