Quality Attributes & Constraints

constraintsSystem Concepts, Architecture & Capabilities, System Requirement & Functions

Quality attributes are Non-Functional Requirements that more or less restrict the Functions and features of a system. These are mostly “How” questions, i.e. how fast, how big, how heavy, how expensive, how long-lasting, how robust, how safe? These requirements often have to be balanced against each other. For this purpose, minimum achievable and desired values ​​are often given. P4 also requires that these are put in a clear order (in the form of a QA/C backlog) so that decisions can be made more easily in the event of conflicts.

Constraints are restrictions that must be observed. They correspond to Quality Attributes that have only a minimum value. The sources of Constraints are often regulatory or legal requirements, as well as product norms and standards*. Due to their severely restrictive effect, the Constraints are usually the top priority in the QA/C backlog.

(see also FURPS and ISO / IEC 9126 )

*) Process norms and standards are referenced within the Organization’s Definition of Done (DoD).


Further suitable links:

Events Roles Groups Artifacts
Cluster Planning

Cluster Sync

Cluster Backlog Refinement

Cluster Review


Cluster Product Owner

Cluster System Engineer


Portfolio Owner

Portfolio Architect

Team Product Owner Group

Team System Engineer Group


Cluster Product Owner Group

Cluster System Engineer Group

Inspectable Results

Team DoD


Usable Knowledge & System Increment

Cluster DoD


Systems & Applications

System Platforms & Variants

Organisation DoD