I am currently writing two applications that need to do some limited communication between themselves. The first application is the UI application and the 2nd application is a worker/processing application (might be running on a different server).
Sometimes I would like the 1st application to be able to tell the 2nd application to take a pause so that the 1st application can have full control.
At this stage I am gathering ideas on how this could be solved.
Any thoughts would be appreciated.

Thanks,
Einar