# IT:AD:FURPS #

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* See also:
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* [[IT/AD/Supplemental Specifications/]]
    * [[IT/AD/Non-Functional Requirements/]]
    * [[IT/AD/Requirements/]]
    * [[IT/AD/ISO 9126/]]
    * [[Business/Concepts/Quality/]]


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<panel title="Summary">

FURPS was an acronym to classify requirements outside of Domain (ie Business) [[IT/AD/Functional Requirements/]].

The most important thing to know about FURPS is: it's supercedd by [[IT/AD/ISO 25010/]].


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## Notes ##

FURPS+ stands for:

* Function Requirements: cross-system requirements.
* Usability Requirements: UX consistency, usability, accessibility, aesthetics.
* Reliability Requirements: availability, accuracy, recoverability.
* Performance Requirements:  throughput, response time, recovery time, start-up time, and shutdown time.
* Supportability Requirements: testability, adaptability, maintainability, compatibility, configurability, installability, scalability, and localizability.

The '+' define the following constraints:
* Design requirements: architectural, infrastructural constraints.
* Implementation requirements: coding constraints (standards, language, resource limits). 
* Interface requirements (SAML, REST, throughput, schedule, format, with what system)
* Physical requirements (not often an issue with software, but location, shape, size, weight)


### ACiD
* Advantages:
    * In addition to providing a way of classifying [[IT/AD/Non-Functional Requirements/]], [[IT/AD/FURPS+/]] provides a framework to define *System* [[IT/AD/Functional Requirements/]].
* Considerations:
    * The acronym is valuable at ensuring key requirements are not missed -- but there is risk in getting complacent and believing the acronym covers all requirements. 
        * This is why [[IT/AD/FURPS/]] ended up being replaced by first [[IT/AD/ISO 9126/]] and then [[IT/AD/ISO 25010/]]
* Disadvantages:
    * The term *Supplemental* in an unfortunate choice: stakeholders do not readily see their value, instead perceiving the supplemental specifications as afterthoughts to the Functional Requirements.


## Resources
* http://www.ibm.com/developerworks/rational/library/4706.html#N100A7