Patent ID: 7805152

Claim:
A system for Push-To-Talk (PTT) communication over cellular network, the system comprising: a first PTT multicast group comprising one or more PTT-capable communication devices configured to communicate in half duplex PTT mode using a first PTT encoding-decoding format supported by coders-encoders of the PTT-capable communication devices of the first PTT multicast group; a second PTT multicast group comprising one or more other PTT-capable communication devices configured to communicate in half duplex PTT mode using a second PTT encoding-decoding format supported by coders-encoders of the PTT-capable communication devices of the second PTT multicast group; wherein the system further comprises virtual PTT multicast group comprising a first network element and a second network element configured to communicate in half duplex PTT mode using a third PTT encoding-decoding format, wherein the first network element is: (a) to receive, as listener in the first PTT multicast group, a PTT vocal message encoded in the first PTT encoding-decoding format; (b) to transcode the PTT vocal message from the first PTT encoding-decoding format to the third PTT encoding-decoding format; (c) to transmit, as sender in the virtual PTT multicast group, the PTT vocal message encoded in the third PTT encoding-decoding format, to the second network element; wherein the second network element is: (a) to receive, as listener in the virtual PTT multicast group, the PTT vocal message encoded in the third PTT encoding-decoding format; (b) to transcode the PTT vocal message from the third PTT encoding-decoding format to the second PTT encoding-decoding format; (c) to transmit, as sender in the second PTT multicast group, the PTT vocal message encoded in the second PTT encoding-decoding format.