Audio conferencing system

• US 6,539,087 B1
• Filed: 11/17/2000
• Issued: 03/25/2003
• Est. Priority Date: 11/17/1999
• Status: Expired

• Current Assignee: Avaya Management L.P. (Avaya Incorporated)
• Original Assignee: Spectel Operations Limited (Avaya Incorporated)
• Inventors: Horne, Robert S., Watson, John T., Martel, Paul P., Walsh, Bruce E., Baun, Philip J. Jr.
• Primary Examiner(s): Matar, Ahmad F.
• Assistant Examiner(s): AGDEPPA, HECTOR A
• Application Number:
  US09/715,906
• Time in Patent Office: 858 Days
• Field of Search: 370/260-266, 379/202-1-2
• US Class Current: 379/202.01
• CPC Class Codes: H04M 3/56 Arrangements for connecting several subscribers to a common circuit, i.e. affording conference facilities video conference systems H04N7/15
• CPC Class Codes: H04M 3/568 audio processing specific to telephonic conferencing, e.g. spatial distribution, mixing of participants echo suppression in two-way loud-speaking telephone systems H04M9/02; sound field processing per se H04S7/30

Abstract

According to the principles of the invention, there is provided a conferencing system that dynamically assigns calls to DSP resources. The system may attempt to process each audio conference on a single DSP node, so that information about conference participants does not need to be shared across DSP nodes. Further, the mapping of call channels to resources within a DSP node may be automated so that it is transparent to a conferencing system control application. Where more than one DSP node is required for a particular conference, there is further provided a system for linking DSP nodes. There are also provided methods for managing audio conferencing resources.

Claims

1. A method for managing channels within an audio conferencing system comprising:

receiving a call on a channel, the call associated with a conference;

identifying a first resource having a predetermined capacity to receive additional conferences, the first resource having a plurality of channels and operating under control of a processor to handle audio conferences;

mapping the channel to one of the plurality of channels of the first resource if the capacity of the first resource is sufficient to add the channel;

moving at least one of the plurality of channels of the first resource associated with a second conference to at least one other resource if the capacity of the first resource is not sufficient to add the channel;

for respective conferences, determining a predetermined number of highest talk level channels associated with the respective conference based on a comparison of channels of the resources having channels associated with the respective conference, the predetermined number independent of a total number of resources having channels associated with the respective conference; and

summing the predetermined number of highest talk level channels as output for the respective conference.

2. The method of claim 1 further comprising linking a plurality of resources to provide a conference that is distributed among the plurality of resources.

3. The method of claim 1 wherein the first resource is a digital signal processor and the second resource is a digital signal processor.

4. The method of claim 1 wherein the predetermined capacity to receive additional conferences is determined using a spacing parameter, the spacing parameter indicative of a capacity for growth of conferences on a resource.

5. The method of claim 1 wherein moving a channel includes moving the channel in a manner that is inaudible to a human listener.

6. The method of claim 1 further comprising reallocating conferences among a plurality of resources at predetermined times.

7. The method of claim 6 wherein predetermined times include at least one of fixed intervals, the beginning of a new conference, or the end of an existing conference.

18. The method of claim 1, comprising:

determining a switch delay indicative of a delay for switching a line from a source resource to a target resource;

buffering audio data for a line from the source resource at the target resource for an amount of time at least as great as the switch delay, the audio data including talk data for the line;

transferring conference data for the line from the source resource to the target resource, the conference data including state data for the line;

switching the line from the source resource to the target resource; and

using the buffered audio data to maintain audio continuity while switching the line.

23. The method of claim 1, comprising:

detecting a loss of one of the at least one other resource;

identifying one or more lines of an audio conference associated with the other resource; and

allocating the one or more lines to one of the first or second resources.

8. An audio conferencing system comprising:

a plurality of network interface cards connected by a first bus to a host and connected by a second bus to a plurality of digital signal processing units, and further connected to one or more telecommunications lines, each digital signal processing unit comprising a plurality of digital signal processing resources configured to manage channels in one or more audio conferences associated with one or more of the telecommunications lines, and each digital signal processing unit including a processor connected in a communicating relationship with the host and connected in a communicating relationship with the digital signal processing resources of the digital signal processing unit, each digital signal processing unit further including a memory, the memory storing state information relating to one or more audio conferences and the memory connected in a communicating relationship with the host, and each digital signal processing unit further including a switch for selectively coupling the digital signal processing resources of the digital signal processing unit to the second bus, the host accessing the processor, memory, and switch of one or more of the digital signal processing units to dynamically assign digital signal processing resources to one or more conferences present within the audio conferencing system.

9. The system of claim 8 wherein the first bus includes a time-slot interchange bus.

24. The audio conferencing system of claim 9, wherein:

each of the plurality of network interface cards couples one or more lines to the time-slot interchange bus using fixed time slots, the switch operable under control of the host to couple with one or more predetermined time slots of the time-slot interchange bus; and

a local time-slot interchange bus, the local bus transmitting data among the digital signal processing resources and the switch,

whereby any one of the one or more lines can communicate with any one of the digital signal processing resources and whereby a time slot associated with the line on the time-slot interchange bus is maintained.

10. A method for managing conferences within an audio conferencing system, the method comprising:

identifying a first resource with a predetermined capacity to receive additional conferences, the first resource having a plurality of channels and operating under control of a processor to handle audio conferences;

identifying a second resource with a predetermined capacity to receive additional conferences, the second resource having a plurality of channels and operating under control of a processor to handle audio conferences, the capacity of the second resource being less than the capacity of the first resource, and the second resource including a conference;

moving the conference on the second resource to the first resource if the first resource has a capacity to include the conference, and attempting to identify a third resource if the first resource does not have the capacity to include the conference;

for respective conferences, determining a predetermined number of highest talk level channels associated with the respective conference based on a comparison of channels of the resources having channels associated with the respective conference, the predetermined number independent of a total number of resources having channels associated with the respective conference; and

summing the predetermined number of highest talk level channels as output for the respective conference.

11. The method of claim 10 further comprising repeating identifying a first resource, identifying a second resource, and conditionally moving the conference at predetermined times to balance a distribution of conferences among a plurality of resources.

12. The method of claim 10, comprising:

establishing a link line from the first resource to the second resource; and

transmitting data from the first resource to the second resource.

13. The method of claim 12 wherein the data includes talk levels for one or more lines participating in a conference.

14. The method of claim 12 wherein the link line is formed using a time-slot interchange bus.

15. The method of claim 12 further comprising transmitting data from the second resource to the first resource.

16. The method of claim 15 further comprising establishing a plurality of bi-directional links among a plurality of audio conferencing resources.

17. The method of claim 12 wherein the data includes state data for one or more of the one or more lines or conferencing resources.

19. A method for managing audio conferencing resources comprising:

detecting a loss of a first physical resource, the first physical resource being a resource for conducting at least one audio conference;

identifying one or more audio conferences of the at least one audio conference associated with the first physical resource;

identifying a second physical resource, the second physical resource being a resource for conducting at least one audio conference, and the second physical resource having a capacity for the one or more conferences;

allocating the one or more conferences to the second physical resource;

for respective conferences, determining a predetermined number of highest talk level channels associated with the respective conference based on a comparison of channels of the physical resources having channels associated with the respective conference, the predetermined number independent of a total number of physical resources having channels associated with the respective conference; and

summing the predetermined number of highest talk level channels as output for the respective conference.

20. The method of claim 19 wherein the loss is due to at least one of a power failure or a component failure.

21. The method of claim 19 wherein the loss is due to an intentional removal of a resource.

22. The method of claim 19 further comprising repeating the steps of detecting a loss, identifying one or more audio conferences associated with the first physical resource, identifying a second physical resource and allocating the one or more conferences to the second physical resource continuously.