COMMUNICATION DEVICE AND REPEATING DEVICE EQUIPPED WITH HOLD CONTROL FUNCTION AND HOLD CONTROL METHOD THEREOF

摘要

PROBLEM TO BE SOLVED: To enable efficient and economical holding operation as to holding control over a call even when holding functions of both devices which have the call are different. SOLUTION: A communication device which has a function of holding an active communication with a communication partner by sending a 1st request signal to the communication partner and a function of holding the communication by sending a 2nd request signal to the communication partner and receiving an answer signal from the communication partner is so constituted that the 1st request signal is sent to the communication partner on detecting the answer signal not being received with a predetermined time after the 2nd request signal is sent to the communication partner. Consequently, the communication partner which does not have the holding function using the 2nd request signal can also be held forcibly.