Glossary · System coordination, integration and orchestration
Hardware-software allocation
Also known as: HW/SW allocation, hardware-software partitioning
German: Hardware-Software-Zuordnung
In systems engineering, hardware-software allocation is the decision about which functions of a system are realized in hardware and which in software, and on which hardware units each software component runs.
- System integration
In one sentence
Hardware-software allocation decides which functions are realized in hardware or software and on which hardware each software component runs.
Example
The team allocates overspeed detection to a dedicated safety relay module, while speed ramp calculation runs as software on the drive controller.
How it applies
- Systems engineering: The allocation affects cost, performance, updateability and timing. Software is easier to change; hardware can be faster and more deterministic.
- Functional safety: Allocating safety functions to hardware or software changes the requirements that apply, for example software safety requirements under IEC 61508-3. Allocating redundant channels to the same hardware can introduce a Common-cause failure (CCF).
- Documentation: Record the allocation and its rationale in the architecture documentation. Service documentation needs it to explain whether a fault is fixed by a part replacement or by a software update.
Hardware-software allocation vs. function allocation
Function allocation assigns functions to any kind of element, including people and external systems. Hardware-software allocation is the specific case of splitting technical functions between hardware and software.