1.Two 10/100 Ethernet 2.Echo cancellation for Speakerphone 3. ... (Radio over IP)technology is to convert the audio and PTT signals in a radio terminal into IP packets and then ... system in high performance ARM 9 Processor Basic FeaturesSupport a PTT port LEDs for Power, Ready, Status, WAN, PC, FXS Call ... Codec: G.711 (A/µ law), G.729A/B, G.723.1 DTMF: RFC 2833, In-band DTMF, SIP INFO Physical and ...