Systems Engineering

The third major step in the systems engineering process is Requirements Allocation. To ensure all the top level requirements will be met, they are assigned to one or more functions to implement. The assignment may be the whole requirement, or by dividing it into parts and then assigning the parts to separate functions. Allocated requirements are documented in lower level requirements documents or specifications that apply to parts of a project. Traceability is being able to trace the links between lower and higher level requirements and the logic of how they were generated. At the lowest level, a subset of the requirements are assigned to a particular hardware or software item, skilled staff, procedures, facilities, interfaces, services, or other elements of the final system. With a complex project, software tools become very useful for the requirements allocation and tracking process. They can help manage the mass of details, and ensure everyone on a project has the most current information.

Requirements allocation is not a one-time task, although it is weighted towards the early stages of a project. As design and testing make progress, they can provide feedback and adjustment to the assigned requirements. These changes propagate to higher levels, and by tracing back their impacts, you can determine how they affect the top-level goals of the project. Changes can also have sideways effects at the same level. For example, an increase in weight of one part of a system may require weight-saving efforts elsewhere to not affect top level performance.