Patent ID: 6400709
Filing Date: 2002-06-04
Classification: H04M

Abstract:
Apparatus for transmitting telephone calls over a data network using a packet switching protocol, said apparatus comprising:a telephone; a transmitting gateway and a receiving gateway, each of said transmitting and receiving gateways being connected to the data network, said transmitting gateway including audio processing means for conducting telephone calls with said telephone, digitizing and packetizing audio signals received from said telephone, and transmitting the digitized packetized audio signals over the data network to the receiving gateway, said receiving gateway being arranged to convert digitized packetized audio signals to analog audio signals for transmission to a voice processing system; means included at said transmitting gateway to monitor said audio signals received from said telephone and to determine whether said audio signals are suspected of having a control tone therein; means responsive to said means to monitor and to determine for delaying transmission of any portion of said received audio signal if said means to monitor and to determine indicate that said portion is suspected of being a control tone; means responsive to said means for delaying for verifying, based upon additional portions of said received audio signal, whether said portion and said additional portions are verified to contain a control tone; and means responsive to said means for verifying for (i) discarding all portions containing said control tone and sending over said data network a digital signal indicative of said tone and its value if said tone is verified and for (ii) sending said portions as packetized audio data if said tone is not verified after being suspected.