2. 4. Communication between visualization client and visualization server

Besides driving the user interface on the client's site, the JAVA applet has a second task. As soon as the user's input is collected and the user's data is accessed, the applet builds up a socket communication link to the visualization server. The visualization server is independent of the WWW server which was used to download the front-end to the client's site. A separate communication channel is used to send the data to the visualization server (Figure 1). After having received the data, the visualization server will create the visualization according to the controls set by the user in the front-end. After the visualization is created, the JAVA applet on the client's site is notified in order to initiate the downloading of the visualization.