I need a remote & local software solution (a web page interface + a Windows app.) to activate and deactivate a sine wave sound on my PC using an ON/OFF button on a remote web page.
This remote button will be used simultaneously by multiple persons in different browsers/PCs so its appearance (ON or OFF) must be updated in real-time everywhere. I mean, if an user switches the button ON it must IMMEDIATELY change its appearance (ON) in the browsers of the other users too, and viceversa for OFF.
ALL the updates must happen in real-time therefore you CAN'T use a "polling" method. You must use a "push" (real-time) method, like a permanent TCP connection.