Introduction to System Modeling

A model is a simplified representation of a system at some particular point in time or space intended to promote understanding of the real system. A system is understood to be an entity which maintains its existence through the interaction of its parts. A model is a simplified representation of the actual system intended to promote understanding. Whether a model is a good model or not depends on the extent to which it promotes understanding. Since all models are simplifications of reality there is always a trade-off as to what level of detail is included in the model. If too little detail is included in the model one runs the risk of missing relevant interactions and the resultant model does not promote understanding. If too much detail is included in the model the model may become overly complicated and actually preclude the development of understanding.

System modeling shows how the system should be working. To construct a system model, the system engineer should consider the following factors :
- Assumptions : It reduces the number of possible permutations and variations, thus enabling a model to reflect the problem in a reasonable manner.
- Simplifications : It enable the model to be created in a timely manner.
- Limitations : It helps to bound the system.
- Constraints : It will guide the manner in which the model is created and the approach taken when the model is implemented.
- Preferences : It indicates the preferred architecture for all data, functions, and technology. The preferred solution sometimes comes into conflict with other restraining factors.yet, customer satisfaction is often predicated on the degree to which the preferred approach is realized.