An apparatus for and a method of audio recording in packet based telephony
systems. Using the present invention, the equivalent of four audio
channels are recorded utilizing only two recording channels. Each channel
recorded comprises the stream of packets generated and transmitted by
each endpoint to the other side. The RTP packets include the samples
generated by the particular endpoint in addition to the timestamp of the
samples received from the other side actually played by the endpoint. The
recording device has knowledge of what was played at the other endpoint
in order to accurately playback the audio samples generated by and
received from the other endpoint. The recording device receives a packet
stream containing the audio generated on each endpoint and the timestamp
of the packet from the other side that was played on the endpoint. The
recording device can reconstruct from this data the audio signal that was
actually played on each endpoint.