“…Usually, the control of several system modules (e.g., unit power and low level control) is proprietary and cannot be modified by user, other levels are considered open (e.g., communication interface and high-level control), i.e., they are based on hardware and software standards with specifications of open interface. In (Pritschow & Altintas, 2001), (Lutz & Sperling, 1997) and (Ford, 1994), the "degree of openness" of a system is defined in agreement with access concept to controller layers, like this, they can be classified in three categories: Proprietary: That system modality allows the access just to application layer, being therefore, a closed system. In those systems is extremely difficult or impossible the integration of external modules.…”