Complexity of the system design problem

The system design problem describes the process used to translating the need or requirements for a system into an actual design. It requires selecting components from a given set and matching the interfaces between them. Those that can be connected to meet the top-level system´s input and output requirements are tested to see how well they meet the system´s performance and cost goals. We prove that this system design process is NP-complete by restricting the knapsack problem, which is known to be NP-complete, to an instance of the system design process problem. The results indicate that designing optimal systems with deterministic, polynomial-time procedures is not possible.