I'm setting up a "Panic Button" for our Front Office. The concept is to have a master Arduino with the button and 4 other Arduinos with Strobes and/or alarms to alert the rest of the staff. The bells and whistles are fairly straight forward. My only block is how to have the remote Arduinos poll the master and receice a simple on/off value over the existing ethernet/wifi network (necessary because we are physically 2 different buildings so bluetooth or standard serial communicaitons would be prohibitive). Master will be hardwired to ethernet while the remotes will need to be wifi. Any and all suggestions would be greatly appreciated.