Dynamic selection of interworking functions in a communication system

• US 6,359,896 B1
• Filed: 02/27/1998
• Issued: 03/19/2002
• Est. Priority Date: 02/27/1998
• Status: Expired due to Term

• Current Assignee: Avaya Incorporated
• Original Assignee: Avaya Technology Corporation Miami Lakes FLA US
• Inventors: Liu, James C., Iyengar, Venkatesh G., Choy, Vincent H., Baker, Albert D., Rose, Eileen P.
• Primary Examiner(s): Kizou, Hassan
• Assistant Examiner(s): LOGSDON, JOSEPH B
• Application Number:
  US09/031,581
• Time in Patent Office: 1,481 Days
• Field of Search: 370/236, 370/477, 370/467, 370/466, 370/271, 370/260, 370/347, 370/252, 370/259, 370/310, 370/357, 370/359, 370/360, 370/400, 370/410, 370/913, 379/230, 455/426, 455/413, 348/15, 395/200.68
• US Class Current: 370/410
• CPC Class Codes: H04L 69/08 Protocols for interworking; Protocol conversion
• CPC Class Codes: H04L 9/40 Network security protocols
• CPC Class Codes: H04Q 2213/13034 A/D conversion, code compression/expansion
• CPC Class Codes: H04Q 2213/1305 Software aspects
• CPC Class Codes: H04Q 2213/13095 PIN / Access code, authentication
• CPC Class Codes: H04Q 2213/13098 Mobile subscriber
• CPC Class Codes: H04Q 2213/13103 Memory
• CPC Class Codes: H04Q 2213/13106 Microprocessor, CPU
• CPC Class Codes: H04Q 2213/13196 Connection circuit/link/trunk/junction, bridge, router, gateway
• CPC Class Codes: H04Q 2213/13204 Protocols
• CPC Class Codes: H04Q 2213/13213 Counting, timing circuits
• CPC Class Codes: H04Q 2213/13292 Time division multiplexing, TDM
• CPC Class Codes: H04Q 2213/13337 Picturephone, videotelephony
• CPC Class Codes: H04Q 2213/13353 Routing table, map memory
• CPC Class Codes: H04Q 3/625 Arrangements in the private branch exchange
• CPC Class Codes: H04W 8/245 from a network towards a terminal
• CPC Class Codes: Y10S 370/913 Wireless or radio

Abstract

The invention provides techniques for selecting, on a dynamic basis, an interworking function (IWF) that can modify a communication protocol to a particular format required by bridged terminal equipment in a communication system. The IWF can be selected to ensure compatibility between transmission bandwidth, coding and other format parameters of a call and the corresponding parameters of its destination terminal in the system. An IWF in accordance with the invention may be utilized to allow a user to bind to different terminals having different capabilities over the duration of a given call. An IWF in accordance with the invention may also be used to insert additional data, retrieved from a database of the switch, into a reverse portion of the call directed from the destination terminal to the source terminal. The invention can thus be used to ensure that the established bandwidth between the destination terminal and the source terminal is substantially bidirectionally symmetric.

Claims

1. A method for processing a call received in a switch of a communication system, the method comprising the steps of:

identifying a parameter of the call;

retrieving previously-stored information regarding a corresponding parameter of a destination terminal of the call, the destination terminal being determined based on an association established in the switch on a dynamic basis between the destination terminal and at least one other terminal of the system; and

processing the call in accordance with at least one inter working function selected from a set of inter working functions implemented in the switch, wherein the selected interworking function is operative to provide compatibility between the parameter of the call and the corresponding parameter of the destination terminal.

2. The method of claim 1 wherein the parameter of the call is a service type associated with the call.

3. The method of claim 1 wherein the parameter of the call is a bandwidth utilized by the call.

4. The method of claim 1 wherein the parameter of the call is a transport stream characteristic of the call.

5. The method of claim 1 wherein the parameter of the call is a voice coding technique used in the call.

6. The method of claim 1 wherein the processing step includes inserting a transcoder implementing the interworking function between an input receiving the call and the destination terminal.

7. The method of claim 6 wherein the call is a voice call and the transcoder is an ADPCM-to-PCM transcoder for interworking the voice call.

8. The method of claim 1 wherein the call is moved from the destination terminal to at least one other terminal of the system during the call, and the processing step further includes the step of processing the call using a first interworking function to provide compatibility with the destination terminal and a second interworking function to provide compatibility with the other system terminal.

9. The method of claim 1 wherein the processing step includes the step of inserting additional data, for presentation in a user-perceptible manner at a source terminal of the call, the additional data being retrieved from a database of the switch, into a reverse portion of the call directed from the destination terminal to the source terminal of the call.

10. The method of claim 9 wherein the call is a video call, the destination terminal is a terminal without video generating capability, and the additional data is video data retrieved from the database and inserted in a signal delivered from the destination terminal to the source terminal as part of the reverse portion of the call.

11. The method of claim 1 wherein the call is a video call including a transport stream, and the processing step further includes:

extracting voice samples from the transport stream;

transcoding the voice samples to match one or more parameters of the destination terminal; and

delivering the voice samples to the destination terminal.

12. The method of claim 11 further including the step of inserting additional video data, retrieved from a database of the switch, into a transport stream directed, in a reverse portion of the call, from the destination terminal to a source terminal of the call, such that the established bandwidth between the destination terminal and the source terminal is substantially bidirectionally symmetric.

13. An apparatus for processing a call in a switch of a communication system, comprising:

a processor implementing at least one interworking function selected from a set of interworking functions implemented in the switch, wherein the selected interworking function is operative to provide compatibility between a parameter of the call and a corresponding parameter of a destination terminal of the call, the destination terminal being determined based on an association established in the switch on a dynamic basis between the destination terminal and at least one other terminal of the system; and

a memory for storing information regarding the corresponding parameter of the destination terminal.

14. The apparatus of claim 13 wherein the parameter of the call is a service type associated with the call.

15. The apparatus of claim 13 wherein the parameter of the call is a bandwidth utilized by the call.

16. The apparatus of claim 13 wherein the parameter of the call is a transport stream characteristic of the call.

17. The apparatus of claim 13 wherein the parameter of the call is a voice coding technique used in the call.

18. The apparatus of claim 13 wherein the processor includes a transcoder implementing the interworking function, wherein the transcoder is inserted between an input of the switch which receives the call and the destination terminal.

19. The apparatus of claim 18 wherein the call is a voice call and the transcoder is an ADPCM-to-PCM transcoder for interworking the voice call.

20. The apparatus of claim 13 wherein the call is moved from the destination terminal to at least one other terminal of the system during the call, and the processor is further operative to process the call using a first interworking function to provide compatibility with the destination terminal and a second interworking function to provide compatibility with the other system terminal.

21. The apparatus of claim 13 wherein the processor is further operative to insert additional data, for presentation in a user-perceptible manner at a source terminal of the call, the additional data being retrieved from a database of the switch, into a reverse portion of the call directed from the destination terminal to the source terminal of the call.

22. The apparatus of claim 21 wherein the call is a video call, the destination terminal is a terminal without video generating capability, and the additional data is video data retrieved from the database and inserted in a signal delivered from the destination terminal to the source terminal as part of the reverse portion of the call.

23. The apparatus of claim 13 wherein the call is a video call including a transport stream, and the processor is further operative to extract voice samples from the transport stream, to transcode the voice samples to match one or more parameters of the destination terminal, and to deliver the voice samples to the destination terminal.

24. The apparatus of claim 23 wherein the processor is further operative to insert additional video data, retrieved from a database of the switch, into a transport stream which is directed, in a reverse portion of the call, from the destination terminal to a source terminal of the call, such that the established bandwidth between the destination terminal and the source terminal is substantially bidirectionally symmetric.

25. A method for processing a call received in a switch of a communication system, the method comprising the steps of:

identifying a parameter of the call;

retrieving previously-stored information regarding a corresponding parameter of a destination terminal of the call; and

processing the call in accordance with at least one interworking function selected from a set of interworking functions implemented in the switch, wherein the selected interworking function is operative to provide compatibility between the parameter of the call and the corresponding parameter of the destination terminal;

wherein the call is moved from the destination terminal to at least one other terminal of the system during the call, and the processing step further includes the step of processing the call using a first interworking function to provide compatibility with the destination terminal and a second interworking function to provide compatibility with the other system terminal.

26. A method for processing a call received in a switch of a communication system, the method comprising the steps of:

identifying a parameter of the call;

retrieving previously-stored information regarding a corresponding parameter of a destination terminal of the call; and

processing the call in accordance with at least one interworking function selected from a set of interworking functions implemented in the switch, wherein the selected interworking function is operative to provide compatibility between the parameter of the call and the corresponding parameter of the destination terminal;

wherein the call is a video call including a transport stream, and the processing step further includes;

extracting voice samples from the transport stream;

transcoding the voice samples to match one or more parameters of the destination terminal; and

delivering the voice samples to the destination terminal.

27. An apparatus for processing a call in a switch of a communication system, comprising:

a processor implementing at least one interworking function selected from a set of interworking functions implemented in the switch, wherein the selected interworking function is operative to provide compatibility between a parameter of the call and a corresponding parameter of a destination terminal of the call; and

a memory for storing information regarding the corresponding parameter of the destination terminal;

wherein the call is moved firm the destination terminal to at least one other terminal of the system during the call, and the processor is further operative to process the call using a first interworking function to provide compatibility with the destination terminal and a second interworking function to provide compatibility with the other system terminal.

28. An apparatus for processing a call in a switch of a communication system, comprising:

a processor implementing at least one interworking function selected from a set of interworking functions implemented in the switch, wherein the selected interworking function is operative to provide compatibility between a parameter of the call and a corresponding parameter of a destination terminal of the call; and

a memory for storing information regarding the corresponding parameter of the destination terminal;

wherein the call is a video call including a transport stream, and the processor is further operative to extract voice samples from the transport stream, to transcode the voice samples to match one or more parameters of the destination terminal, and to deliver the voice samples to the destination terminal.