Real-time middleware for the requirements of distributed process control

Process control applications are large distributed systems containing a vast number of communication links between their fragments. These links may have unique properties with respect to communication mechanisms and real-time quality of service attributes. Frequent dynamic reconfiguration of the application is only possible if these links can be updated automatically. This paper explores the possibility of using commercially available standard-based real-time middleware for managing the communication links. The special requirements of process automation are described and used to derive test cases for middleware products. Some results and experiences with the real-time publish-subscribe middleware are presented.