Call clearing for legacy mobile circuit switched domain wireless systems

• US 7,436,817 B2
• Filed: 12/20/2002
• Issued: 10/14/2008
• Est. Priority Date: 03/08/2002
• Status: Expired due to Fees

• Current Assignee: Blackberry Limited
• Original Assignee: Nortel Networks Limited (Nortel Networks Corporation)
• Inventors: Bienn, Marvin, Bharatia, Jayshree A., Pendleton, Amy
• Primary Examiner(s): Chan, Wing F.
• Assistant Examiner(s): Mais, Mark A.
• Application Number:
  US10/326,324
• Publication Number:
  US 20030169729A1
• Time in Patent Office: 2,125 Days
• Field of Search: 370/352, 370/353, 370/354, 370/355, 370/356, 370/401, 370/466, 370/467
• US Class Current: 370/352
• CPC Class Codes: H04L 12/4633 Interconnection of networks using encapsulation techniques, e.g. tunneling
• CPC Class Codes: H04L 12/66 Arrangements for connecting between networks having differing types of switching systems, e.g. gateways
• CPC Class Codes: H04L 69/08 Protocols for interworking; Protocol conversion
• CPC Class Codes: H04L 9/40 Network security protocols

Abstract

A telecommunications system having a first PS network, second PS network and a third circuit-switched core network includes a system for terminating a legacy domain circuit-switched communication upon receipt of a trigger signal requesting termination of communication. The system includes first and second functional entities in each network. The first and second functional entities of the first network can communicate signals over an interface using a PS protocol. The first and second functional entities of the second network can communicate signals over an interface using a PS protocol. The first functional entity of the first network can communicate packet data to and from the first functional entity of the second network. The second functional entity of the first network communicates a PS protocol signal to the second entity of the second network, which then communicates a circuit-switched protocol signal to and from the third circuit-switched protocol core network to terminate the circuit-switched communication.

Claims

1. A telecommunications system comprising:

a first functional entity comprising a mobile gateway and a second functional entity comprising a mobile switching control emulator (MSCe) in first packet switched (PS) network; and

a third functional entity comprising a mobile gateway and a fourth functional entity comprising an MSCe in a second PS network;

said first functional entity and said second functional entity including means for communicating signals using a first PS protocol;

said third functional entity and said fourth functional entity including means for communicating signals using the first PS protocol;

said first functional entity having means for communicating packet data to and from said third functional entity;

said second functional entity having means for mapping a circuit switched (CS) network message to a first PS protocol signal message using a second PS protocol;

said second functional entity further having means for transmitting the first PS protocol signal message to said fourth functional entity using a second PS protocol;

said fourth functional entity further including means for communicating the CS network message using a CS protocol to and from a CS network to terminate the CS communication; and

said second functional entity further including means for communicating a signal using a third PS protocol to and from an access network.

2. The system defined in claim 1, wherein said CS network comprises a public switched telephone network.

3. The system defined in claim 1, wherein said second functional entity comprises means for receiving a trigger signal requesting termination of the CS communication.

4. The system defined in claim 3, wherein said trigger signal is a clear signal from the access network.

5. The system defined in claim 3, wherein said trigger signal is a service release signal from the fourth functional entity using the second PS protocol.

6. The system defined in claim 1, wherein said first PS protocol comprises Megaco protocol.

7. The system defined in claim 1, wherein said second PS protocol comprises SIP protocol.

8. The system defined in claim 1, wherein said CS protocol comprises an open-standards communications protocol.

9. The system defined in claim 8, wherein said CS protocol includes an SS7 REL signal.

10. The system defined in claim 8, wherein said CS protocol includes an SS7 RLC signal.

11. The system defined in claim 1, wherein said means for said second functional entity to communicate signals to and from said fourth functional entity comprises an SIP BYE signal.

12. The system defined in claim 1, wherein said means for said second functional entity to communicate signals to and from said fourth functional entity comprises an SIP OK signal.

13. The system defined in claim 1, wherein said third PS protocol comprises IOS protocol.

14. The system defined in claim 1, wherein said means for mapping the CS communication to the first PS protocol signal message includes means for encapsulating the CS communication within the first PS protocol signal message using the second PS protocol.

15. A method for terminating a communication, the method comprising:

communicating a first signal from a first functional entity in a first network to an access network using a first packet switched (PS) protocol;

communicating a second signal from said first functional entity to a second functional entity in said first network using a second PS protocol;

receiving a third signal from said second functional entity by said first functional entity;

mapping a circuit switched (CS) communication in a CS protocol to a fourth signal, wherein the fourth signal comprises the second PS protocol signal in a third PS protocol;

communicating the fourth signal from said first functional entity to a third functional entity in a second network using the third PS protocol, the second network coupled to a CS network; and

communicating a fifth signal from the third functional entity in the second network to the CS network using the CS protocol.

16. The method defined in claim 15 further comprising communicating a fifth signal to the CS network, wherein the CS network comprises a public switched telephone network.

17. The method defined in claim 15 further comprising receiving by said first functional entity, a trigger signal requesting termination of a CS communication.

18. The method defined in claim 17, wherein said trigger signal includes a clear signal.

19. The method defined in claim 17, wherein said trigger signal includes a service release signal.

20. The method defined in claim 15, wherein said second signal comprises a Megaco subtract trunk signal and a subtract RTP signal.

21. The method defined in claim 15, wherein said third signal comprises a Megaco reply signal.

22. The method defined in claim 15 further comprising communicating signals to and from said CS network using an open-standards CS protocol.

23. The method defined in claim 22, wherein said CS protocol includes an SS7 REL signal.

24. The method defined in claim 22, wherein said CS protocol includes an SS7 RLC signal.

25. The method defined in claim 15, further comprising communicating an SIP BYE signal from said first functional entity to said third functional entity.

26. The method defined in claim 15, further comprising communicating an SIP OK signal from said first functional entity to said third functional entity.

27. A system operable in a first packet switched (PS) network comprising a first mobile switching control emulator (MSCe) for call clearing in a second PS network comprising a second MSCe and a circuit switched (CS) network, the system comprising:

the first MSCe configured for;

receiving from an access network a first signal to trigger initiation of a call clearing action over a first PS protocol;

transmitting a second signal over the first PS protocol to the access network, the second signal relating to clearing the call;

mapping a third signal from the first PS protocol to a second PS protocol, resulting in a fourth signal;

transmitting the fourth signal over a second PS protocol to a media gateway requesting subtraction of a trunk line and subtraction of an RTP bearer channel;

receiving a fifth signal over the second PS protocol from the media gateway;

mapping a sixth input signal from the first PS protocol to a third PS protocol resulting in a seventh signal, wherein the seventh signal comprises a circuit switched (CS) communication mapped into the third PS protocol;

transmitting the seventh signal over the third protocol to the second MSCe; and

receiving an eighth signal over the third protocol from the second MSCe relating to the clearing of the call.

28. The system of claim 27, wherein the first PS protocol comprises IOS protocol.

29. The system of claim 27, wherein the first signal comprises a Clear Request.

30. The system of claim 27, wherein the second PS protocol comprises Megaco protocol.

31. The system of claim 27, wherein the fifth signal comprises a reply to the fourth signal.

32. The system of claim 27, wherein the third PS protocol response comprises SIP protocol.