. . . .Suppose you're licensed to use a 3rd-party Java applet. Suppose that applet periodically communicates with the server and always communicates before being terminated (e.g., save -> close). Suppose that this applet periodically calls web services. Finally, suppose you don't have rights to modify the applet code or web services.

. . . .How do you go about tracking end-users' usage of such an applet? I would be content knowing when an applet was downloaded and its last communique before termination. Here, I'd be assuming the applet was being used the whole time and if there wasn't a save by the end of the work day, I'd assume the download was a fluke.
. . . .It would be much better to capture the applet's call to web services, which would tend to show work being done by virtue of periodic calls (connect the dots).

. . . .I'm exploring ways in which my organization can bill clients on a time and materials basis rather than charging a flat-fee. Having this ability to "audit" is a move towards improving client confidence that they're not being overcharged.

Thanking you,