Abstract: A method for compensating for asynchronous clock sources is presented. A buffer is provided for storing frames received from a packet network. The buffer having a preselected playout delay. Upon detecting a buffer overflow, a drain operation is performed on the buffer and the playout delay is modified to provide a sufficient number of buffer locations for frames to be stored. Upon detecting a buffer underflow, a fill operation is performed on the buffer and the playout delay is modified to provide a sufficient number of frames to be played out.

Abstract: A method for providing fail-over capability in a local branch of a call center includes determining, by a local device, which of a plurality of phones are call center phones. The determination is based on a predetermined rule set. In an alternative embodiment, the method may also include determining, by the local device, which of the plurality of call center phones are available for receiving calls. This may include determining whether a “do not disturb” function of each respective call center phone is invoked, and in response, determining whether the call center phone is available. In addition, this method may involve placing, by the local device, each call center phone into a “do not disturb” mode if the call center phone does not answer a call sent to the call center phone.

Abstract: In a telephony system have management of telephony devices distributed among multiple call management devices, the call management devices use call redirection and relaying of message waiting indications to provide voicemail services to the telephony devices using a centralized voicemail server.

Abstract: Routing a call includes receiving a request to initiate a call session for a call from a caller endpoint to a callee endpoint, where the caller endpoint belongs to an internal network. Whether the call is internal or external is determined. A routing mode is selected in accordance with the determination, and the call is routed according to the selected routing mode.

Abstract: Method for maintaining a virtual presence of a first remote telephone user in a PBX system having a frame relay network connection between two endpoint routers while permitting the first remote user to make local calls includes first signaling a PBX to represent the remote telephone as being off hook; routing a telephone call placed at the remote telephone in accordance with a defined protocol; and when the routed telephone call is terminated, second signaling the PBX to restore the on-hook status of the remote telephone. Preferably, the first and second signaling are performed in-band, in accordance with an FRF.11 or VToA AAL2 voice over packet protocol. The telephone call-routing may be to a public switched telephone network (PSTN) local to the remote telephone or it may be to another remote telephone user at the same site within the PBX system as the first remote telephone user.

Abstract: The method involves transmitting plural endpoint probes to produce plural endpoint probe results indicating the preparedness of the endpoints for calls routed thereto; identifying similarly situated endpoints; and representing each of the similarly situated endpoints by a reduced number of recorded endpoint probe results that substantially represent the inter-connective preparedness of each of the similarly situated endpoints. The apparatus includes a mapping mechanism for mapping the probe results for the similarly situated endpoints into a reduced number of endpoint probe results that substantially represent the inter-connective preparedness of each of the similarly situated endpoints, and a recording mechanism for recording the reduced number of endpoint probe results. Such mapping permits an Internet operating system (IOS) router/gateway to act as an real-time responder/service assurance agent (RTR/SAA) proxy on behalf of non-RTR/SAA capable voice over Internet protocol (VoIP) endpoints.

Abstract: A method for compensating for asynchronous clock sources is presented. A buffer is provided for storing frames received from a packet network. The buffer having a preselected playout delay. Upon detecting a buffer overflow, a drain operation is performed on the buffer and the playout delay is modified to provide a sufficient number of buffer locations for frames to be stored. Upon detecting a buffer underflow, a fill operation is performed on the buffer and the playout delay is modified to provide a sufficient number of frames to be played out.

Abstract: In a telephony voice network having at least two connectable endpoint nodes with a trunk therebetween and a trunking alarm associated with each endpoint node, an alarm aggregation method is proposed. The method involves first detecting a trunking alarm associated with one of the endpoint nodes and second detecting a second trunking alarm associated with another of the endpoint nodes. The method aggregates the results of the first and second detecting to assist in determining a condition of the trunk between the two endpoint nodes. Such an out-of-service condition of the trunk may be signaled onto an outgoing T1/E1 connection coupled with the affected trunk. Preferably, plural connectable endpoint node pairs define plural ones of such trunks therebetween with each of the plural trunks having a trunking alarm associated with each endpoint node pair.

Abstract: Dynamic compressor/decompressor (codec) speed selection includes monitoring a call in a telephone system to determine the type of codec being used thereon and to measure the payload on the codec. The capacity of the codec is determined based upon the determined type of codec being used. Speed selection further includes comparing the determined capacity with the measured payload; and selectively switching the call to a higher operational speed based upon the result of the comparing. Preferably, the monitoring includes detecting a modem answer tone of the telephone call and basing the determination of the type of codec at least partly thereon. The monitoring also preferably includes detecting silence of the telephone call and basing the selective switching at least partly thereon. Echo cancellation and/or suppression is disabled upon such selective switching. In accordance with one embodiment of the invention, the switching includes requesting an up-speed codec.