Device for transmitting push-to-talk message

A device for transmitting a push-to-talk (PTT) message, the device comprising:

• a communication interface;
• and
• an operation processor configured to:
• (a) transmit a first segment group of the PTT message among multiple segments of the PTT message to a first PTT device to an n-th PTT device (where “n” is a natural number equal to or greater than 2) through the communication interface;
• (b) transmit a heartbeat signal to the first PTT device to the n-th PTT device through the communication interface;
• (c) receive an i-th response signal to the heartbeat signal from an i-th PTT device (where “i” is a natural number from 1 to n) through the communication interface;
• (d) allocate, based on the i-th response signal, the i-th PTT device to either one of:
• a first group to which a second segment group of the PTT message among the multiple segments of the PTT message is transmitted without any conversion;
• and a second group to which data obtained by converting all segments of the second segment group of the PTT message is transmitted;
• and
• (e) transmit the second segment group of the PTT message to the first group through the communication interface and transmit the data to the second group through the communication interface.