The termination of the ability of a product to perform a required function or its inability to perform within previously specified limits. [ ISO/IEC 9126-1, ISO/IEC 14598-5, ISO/IEC 25000 ]
Failure [ SIGIST ]: Deviation of the software from its expected delivery or service.
Failure [ IEEE 610.12 ]: The inability of a system or component to perform its required functions within specified performance requirements.
Failure [ ISO/IEC/IEEE 24765 ]: An event in which a system or system component does not perform a required function within specified limits.
- According to Laprie et al.[], "a system failure occurs when the delivered service no longer complies with the specifications, the latter being an agreed description of the system's expected function and/or service". This definition applies to both hardware and software system failures. Faults or bugs in a hardware or a software component cause errors. An error is defined by Laprie et al. as that part of the system which is liable to lead to subsequent failure, and an error affecting the service is an indication that a failure occurs or has occurred. If the system comprises of multiple components, errors can lead to a component failure. As various components in the system interact, failure of one component might introduce one or more faults in another. [ University of Duke ]
- The fault tolerance discipline distinguishes between a human action (a mistake), its manifestation (a hardware or software fault), the result of the fault (a failure), and the amount by which the result is incorrect (the error). [ IEEE 610.12 ]
