Product engineering is a system engineering approach which starts with system analysis.
The system engineer identifies the customer's requirement, determines economic and economic technical, feasibility and allocates performance and function to hardware, software, databases and people the key engineering parts.
An architectural model of the product or system is representations and produced of each major subsystem can be developed. In the final stage the system engineer can built a reactive system model that can be used as the basis for a simulation of behaviour and performance.
The system engineering task culminates with the building of a system specification a document which forms the foundation for all engineering work which follows.