The real-time system is used widely since the 1990's. In the paper some typical design approaches are introduced. Then the object-oriented design approach for real-time system and the use of UML is analyzed.
After the persistent practice in the 1990's,using "Open System" idea to integrate large scale computer systems has been the consenting fact. The new mechanism based on mobile agent is discussed and the core architecture called common agent request broker architecture (CARBA)is established to embody intelligent collaboration in the next generation open system. In order to evaluate whether CARBA is open system,ODP specification is used to validate the openness of CARBA.
