Abstract: In one embodiment, a first audio waveform is produced at a first side of a network connection and then encoded and sent by a first endpoint device to a second endpoint device at a second side of the network connection. A second audio waveform is then detected after being played out by the first endpoint device, the second audio waveform having been produced at the second side of the network connection in response to the second endpoint device playing out the first audio waveform. A round-trip delay is then calculating based on a time period measured from output of the first audio waveform to detection of the second audio waveform. It is emphasized that this abstract is provided to comply with the rules requiring an abstract that will allow a searcher or other reader to quickly ascertain the subject matter of the technical disclosure.

Abstract: In one embodiment, a method includes synchronizing to a common reference timeframe between a sender node and a plurality of receiver nodes connected over a packet-based network. The sender node sends Real-Time Protocol (RTP) frames to the receiver nodes, and also sends a RTP Control Protocol (RTCP) sender report to each receiver node that contains a rendering offset value, each receiver node rendering the RTP frames at a render time equal to a sampling time in units of the common reference timeframe plus the rendering offset value. It is emphasized that this abstract is provided to comply with the rules requiring an abstract that will allow a searcher or other reader to quickly ascertain the subject matter of the technical disclosure.

Abstract: In one embodiment, a system includes a video mixer coupled with an audio mixer for exchange of information that includes a first set of delay values respecting input audio streams received by the audio mixer from a plurality of source endpoints, and output audio streams sent from the audio mixer to a plurality of destination endpoints. The information further including a second set of delay values respecting the corresponding input video streams. The audio mixer calculates end-to-end video delays, and the video mixer calculates end-to-end audio delays. The audio mixer delays the output audio streams to equalize the end-to-end audio and video delays in the event that the end-to-end audio delays are less than the end-to-end video delays, and the video mixer delays the output video streams to equalize the end-to-end audio and video delays in the event that the end-to-end video delays are less than the end-to-end audio delays.

Abstract: A method for volume indication during a communication session includes detecting analog audio at a telephony device. First communication packets are transmitted from the telephony device indicating that the analog audio is being received. The analog audio is encoded to a digital audio stream and second communication packets comprising the digital audio stream are transmitted from the telephony device. In accordance with a particular embodiment, the first communication packets indicate an approximate volume level of the analog audio. The method may also include receiving, at the telephony device, analog video. The analog video is converted to a digital video stream. The digital video stream may be transmitted from the telephony device.

Abstract: In one embodiment, a method includes synchronizing to a common reference timeframe between a sender node and a plurality of receiver nodes connected over a packet-based network. The sender node sends Real-Time Protocol (RTP) frames to the receiver nodes, and also sends a RTP Control Protocol (RTCP) sender report to each receiver node that contains a rendering offset value, each receiver node rendering the RTP frames at a render time equal to a sampling time in units of the common reference timeframe plus the rendering offset value. It is emphasized that this abstract is provided to comply with the rules requiring an abstract that will allow a searcher or other reader to quickly ascertain the subject matter of the technical disclosure.

Abstract: In one embodiment, a system includes a video mixer coupled with an audio mixer for exchange of information that includes a first set of delay values respecting input audio streams received by the audio mixer from a plurality of source endpoints, and output audio streams sent from the audio mixer to a plurality of destination endpoints. The information further including a second set of delay values respecting the corresponding input video streams. The audio mixer calculates end-to-end video delays, and the video mixer calculates end-to-end audio delays. The audio mixer delays the output audio streams to equalize the end-to-end audio and video delays in the event that the end-to-end audio delays are less than the end-to-end video delays, and the video mixer delays the output video streams to equalize the end-to-end audio and video delays in the event that the end-to-end video delays are less than the end-to-end audio delays.

Abstract: A method includes determining information regarding a conference among a plurality of participants. The information may include a respective cumulative talk time of each of the plurality of participants. In accordance with a particular embodiment of the present invention, the respective cumulative talk times of each of the plurality of participants is graphically presented to at least one of the plurality of participants.

Abstract: In one embodiment, a first audio waveform is produced at a first side of a network connection and then encoded and sent by a first endpoint device to a second endpoint device at a second side of the network connection. A second audio waveform is then detected after being played out by the first endpoint device, the second audio waveform having been produced at the second side of the network connection in response to the second endpoint device playing out the first audio waveform. A round-trip delay is then calculating based on a time period measured from output of the first audio waveform to detection of the second audio waveform. It is emphasized that this abstract is provided to comply with the rules requiring an abstract that will allow a searcher or other reader to quickly ascertain the subject matter of the technical disclosure.

Abstract: A method for tracing communications includes receiving trace criteria from a first remote element and determining whether a call signaling message matches the trace criteria. The method includes attaching a trace tag to the call signaling message, if the call signaling message matches the trace criteria. The method further includes transmitting the call signaling message to a second remote element.

Abstract: A method for tracing communications includes receiving trace criteria from a first remote element and determining whether a call signaling message matches the trace criteria. The method includes attaching a trace tag to the call signaling message, if the call signaling message matches the trace criteria. The method further includes transmitting the call signaling message to a second remote element.

Abstract: According to an embodiment of the present invention, an apparatus for performing video conferencing is provided that includes an I-frame injector element operable to intercept I-frame requests from one or more end points and to attempt to service the I-frame requests such that at least a portion of the requests are prevented from propagating back to an originating sender. In more specific embodiments, when a receiver endpoint sends a fast video update (FVU) request upstream, it is intercepted by the I-frame injector element and rather than passing the FVU request to the sender the I-frame injector element replaces a next P-frame from the sender with an I-frame, whereby the I-frame is constructed so that when decoded, it matches the P-frame that it replaced. In still more detailed embodiments, the I-frame injector element operates in one of three modes that are associated with bandwidth parameters.

Abstract: Authenticating an endpoint using a STUN server includes facilitating a communication session between a first endpoint and a second endpoint over a network. A challenge request is sent to the second endpoint. The challenge request attempts to authenticate the second endpoint and includes an identification. The identification is associated with an expected response identification. A response to the challenge request is received from the second endpoint. The response has an actual response identification. The received response is verified to establish whether the second endpoint is legitimate. The second endpoint is legitimate if the actual response identification includes the expected response identification.

Abstract: A method for tracing communications includes receiving trace criteria from a first remote element and determining whether a call signaling message matches the trace criteria. The method includes attaching a trace tag to the call signaling message, if the call signaling message matches the trace criteria. The method further includes transmitting the call signaling message to a second remote element.

Abstract: A method for tracing communications includes receiving trace criteria from a first remote element and determining whether a call signaling message matches the trace criteria. The method includes attaching a trace tag to the call signaling message, if the call signaling message matches the trace criteria. The method further includes transmitting the call signaling message to a second remote element.

Abstract: A method for tracing communications includes receiving trace criteria from a first remote element and determining whether a call signaling message matches the trace criteria. The method includes attaching a trace tag to the call signaling message, if the call signaling message matches the trace criteria. The method further includes transmitting the call signaling message to a second remote element.

Abstract: A method for executing a video conference is provided that includes receiving one or more audio streams associated with a video conference from one or more end points and determining an active speaker associated with one of the end points. Audio information associated with the active speaker may be received at one or more media switches. One or more video streams may be suppressed except for a selected video stream associated with the active speaker, the selected video stream propagating to one or more of the media switches during the video conference. The selected video stream may be replicated such that it may be communicated to one or more of the end points associated with a selected one of the media switches.

Abstract: A method for non-causal speaker selection is provided. In accordance with a particular embodiment of the present invention the method includes receiving a plurality of video streams at a multipoint control unit, each of the plurality of video streams being associated with a respective endpoint of a multipoint conference. A plurality of audio streams may also be received at the multipoint control unit, and each audio stream may be associated with a respective one of the video streams. The audio streams are buffered in respective audio buffers, and the video streams are buffered in respective video buffers. First video data is copied from the video buffers to obtain a low latency video stream for distribution to active conference participants. In a particular embodiment, second video data may be copied from the video buffers to obtain a high latency video stream for distribution to passive conference participants, the high latency video streams being delayed in time with respect to the low latency video stream.

Abstract: A method for executing a video conference is provided that includes receiving one or more audio streams associated with a video conference from one or more end points and determining an active speaker associated with one of the end points. Audio information associated with the active speaker may be received at one or more media switches. One or more video streams may be suppressed except for a selected video stream associated with the active speaker, the selected video stream propagating to one or more of the media switches during the video conference. The selected video stream may be replicated such that it may be communicated to one or more of the end points associated with a selected one of the media switches.

Abstract: A method for executing a video conference is provided that includes receiving one or more audio streams associated with a video conference from one or more end points and determining an active speaker associated with one of the end points. Audio information associated with the active speaker may be received at one or more media switches. One or more video streams may be suppressed except for a selected video stream associated with the active speaker, the selected video stream propagating to one or more of the media switches during the video conference. The selected video stream may be replicated such that it may be communicated to one or more of the end points associated with a selected one of the media switches.

Abstract: Apparatus and methods for matching data rates is useful for a receiver receiving real-time data over a medium. Implementations feature a process establishing a buffer in a receiver; receiving source data from a source having a nominal source data rate, the received source data arriving at an incoming data rate that differs from time-to-time from the nominal source data rate; filling the buffer with source data as it is received at the incoming data rate and emptying the buffer to provide data for consumption in real time at a consumption data rate; setting a rate-matching factor M, the factor M affecting the rate at which the buffer is emptied; and tracking the level of data in the buffer and resetting the value of M to increase the rate at which the buffer is emptied when the buffer fills above a target range, and resetting the value of M to decrease the rate at which the buffer is emptied when the buffer empties below a target range.