Abstract: A plurality of telephone devices responsive to computer commands are connected to a telecommunications switch. A computer controlled apparatus sends command messages to the telephone devices causing them to initiate conventional actions such as dialing. The apparatus receives reply messages from the telephone devices which represent the status of parameters such as ringing associated with the telephone device. Reply messages are identified relative to previously sent command messages. If the actual status of parameters represented by a reply message matches an anticipated status of the parameters corresponding to actions expected in response to a command message, a successful test of the switch functions associated with the command message results. An unmatched condition corresponds to a test failure requiring user analysis.