Abstract: After completion of a voice-over IP call, for example, first information representing a Layer 3 path of a packet flow of a completed call that has passed through a packet-switched network is created. Second information representing a Layer 2 path of a packet flow of the completed call is also created. One or more selected phone call detail records are retrieved, which are associated with the completed call. Thus, the likely path of a troubled call is determined, and phone call detail records associated with key points in the path are located. The first information, second information, and selected phone call detail records are provided to a user for use in evaluating one or more problems experienced in the completed call.

Abstract: A method and apparatus that provide for determining a multilayer switching path are disclosed. In one embodiment of the invention, a Layer 3 path and a Layer 2 path between a source device and destination device are first determined in order to identify the relevant switch engines that perform the multilayer switching. Determining whether the switch engines satisfy a set of criteria identifies the relevant switch engines.

Abstract: In one embodiment, one or more gateways sniff the voice channel during the voice mode. If it is determined that V.8bis signals are being initiated, then the gateway breaks these exchanges by suppressing such signaling, thereby avoiding the above-described detrimental effects. Modem relay communications then are allowed to proceed. Briefly, the method and apparatus involve monitoring a call during a voice mode phase for an initiating signal representative of the defined signaling, the monitoring being performed by a local gateway and, if such an initiating signal is detected during the monitoring, then suppressing such detected signaling in such manner that the signaling does not reach the remote gateway. Preferably, the monitoring is for an initiating signal characterized by a dual tone of defined frequency and duration of approximately 1375 Hz and 2002 Hz for a duration of approximately 400 ms or 285 ms, in agreement with the ITU-T Recommendation V.

Abstract: A technique for processing data carried by a Time Division Multiplexing (TDM) channel in a TDM network. A data stream associated with a TDM channel is monitored to determine if it contains data frames. If so, the channel associated with the data stream enters a clear channel mode which causes data in the data stream to be placed in packets for transfer over the packet network without being modified. Provided the data stream continues to carry data frames, the data stream stays in clear channel mode. After the data stream data no longer carries data frames, the channel exits clear channel mode.

Abstract: A method and system for fax passthrough that can detect fax calls and which can distinguish between fax calls and modem calls. Both V.21 flags and the CM fax signals are detected to determine if a call is a fax call. If a call is from a G3 fax machine, the v.21 flags will be detected. On the other hand if the call is from a SG3 fax machine the CM fax signal will be detected. The method and system therefore detects fax calls and it distinguishes between fax and modem calls in a fax passthrough system.

Abstract: Text is interleaved and transported along with media data over the same real-time Internet Protocol (IP) media transport session. A network processing device identifies text characters corresponding with text signaling. The identified text characters are formatted into text packets and sent over the same real-time IP media transport session used for real-time media transport. The media transport session can identify the sequence that the text characters are transmitted and can specify a maximum character transfer rate.

Abstract: A method and apparatus that provide for determining a multilayer switching path are disclosed. In one embodiment of the invention, a Layer 3 path and a Layer 2 path between a source device and destination device are first determined in order to identify the relevant switch engines that perform the multilayer switching. Determining whether the switch engines satisfy a set of criteria identifies the relevant switch engines.

Abstract: An improved method and system for connecting Super Group 3 fax machines over network gateways that operate using the un-enhanced T.38 protocol. With the present invention, the CM tone is suppressed. Thus a gateway that generates an AnsAm tone, will not receive a CM tone in response. The T.38 protocol does not specify what occurs if a CM tone is not received; however, it has been found that, in practice, existing fax machines fall back to V.21 mode if a CM tone is not received.

Abstract: A method and apparatus that provide for determining a multilayer switching path are disclosed. In one embodiment of the invention, a Layer 3 path and a Layer 2 path between a source device and destination device are first determined in order to identify the relevant switch engines that perform the multilayer switching. Determining whether the switch engines satisfy a set of criteria identifies the relevant switch engines.

Abstract: A mechanism for determining a data link path in a managed network between a source device and a destination device is disclosed. To determine the data link path, a mechanism determines the topology of the network. Information on the topology is needed in order to create a Connected Group space based on the topology. By creating a Connected Group space, the problem of determining a data link path is reduced to an optimization problem of finding the shortest path between the source device and destination device in the managed network. The shortest path is then transformed back into the topology space to reveal the data link path network between the source device and the destination device.

Abstract: A system that packetizes telephone calls using loss-less codecs for transmission over a communication link. The system includes a call admission control mechanism that admits calls for transmission over the communication link. An adaptive system which monitors bandwidth usage and which dynamically provides a feedback loop to the CAC system. The bandwidth allocation for transmission of the calls and the admission of calls is based upon actual bandwidth usage conditions in the system.

Abstract: A network device is disclosed. The network device includes a port to allow the device to communicate on a full bandwidth channel, a main processor to control reception and transmission of data and a compressor. The compressor identifies repeated fixed sequences in the data, and replaces repeated fixed sequences with an identifier sequence, a count of repetitions and the fixed sequence. The network device may have a decompressor instead of, or in addition to, the compressor that can decompress received data that is compressed.

Abstract: A method is disclosed for creating and storing troubleshooting information for diagnosing one or more problems experienced in one or more completed voice calls that are carried by a packet-switched data network. After completion of a voice-over IP call, for example, first information representing a Layer 3 path of a packet flow of a completed call that has passed through the data network is created and stored. Second information representing a Layer 2 path of a packet flow of a completed call that has passed through the data network is also created and stored. From a phone call detail record database, one or more selected phone call detail records are retrieved, which are associated with the completed call from a database of phone call detail records for a large plurality of completed calls. Thus, the likely path of a troubled call is determined, and phone call detail records associated with key points in the path are located.