A software architecture for remote participation at the Textor-94 experiment

The Trilateral Euregio Cluster (TEC) is a collaboration between three plasma-physics institutes: the Laboratory for Plasma Physics at the Koninklijke Militaire School (KMS) in Brussels, Belgium, the FOM Institute for Plasma Physics in Rijnhuizen, the Netherlands and the Institute for Plasma Physics at the Forschungszentrum Jülich (FZJ) in Germany. They jointly perform nuclear fusion experiments at the tokamak reactor ‘Textor-94’ in Jülich. Currently, scientists from FOM and KMS have to be physically present at the Textor-94 control room to participate in experiments. To show that remote participation is feasible, the Dynacore project built a software demonstrator that allows scientists to view measurement data, control measurement equipment and view the status of Textor-94. The demonstrator uses Java applets as clients, C++ servers, and CORBA for communication. The chosen architecture has the following advantages. It is portable, modular and reusable, eases collaboration in software development and optimizes for performance over the Internet. We solved the problems we had with applet security policies, the performance of our design and the integration of legacy systems. Our demonstrator shows that remote participation is feasible. The reactions from potential users are very positive. However, the demonstrator has to be improved for real usage in the future.