What is the difference?
The requirement specification describes what the client needs and why. The system specification explains how and with what the supplier will implement those requirements.
| Requirement specification | System specification | |
|---|---|---|
| Owner | client or appointed planner | supplier |
| Question | what and why? | how and with what? |
| Purpose | tender and comparison | implementation basis |
Quality rules
- Number and version requirements.
- Separate function, constraint and acceptance evidence.
- Keep dependencies, contradictions and open points visible.
- Preserve solution freedom where no justified constraint exists.
Current framework
The valid VDI/VDE 3694:2014-04 provides a structure for automation systems. A revision is in progress; the announced project is not yet a valid new edition.
Application: WMS requirement specification.
Requirement and system specification in practice: Our services overview brings together the relevant planning and consulting approaches.