Method, system and gateway device for enabling interworking between IP and CS networks

• US 20040190498A1
• Filed: 05/21/2003
• Published: 09/30/2004
• Est. Priority Date: 03/25/2003
• Status: Active Grant

• Current Assignee: Intellectual Ventures I LLC (Intellectual Ventures LLC)
• Original Assignee: Intellectual Ventures I LLC (Intellectual Ventures LLC)
• Inventors: Kallio, Juha, Mutikainen, Jari, Jylha-Ollila, Markku
• Granted Patent: US 7,898,990 B2
• Time in Patent Office: Days
• US Class Current: 370/352
• CPC Class Codes: H04L 65/1016 IP multimedia subsystem [IMS]
• CPC Class Codes: H04L 65/1026 at the edge
• CPC Class Codes: H04L 65/1036 at the edge
• CPC Class Codes: H04L 65/1043 Gateway controllers, e.g. media gateway control protocol [MGCP] controllers
• CPC Class Codes: H04L 65/1104 Session initiation protocol [SIP]
• CPC Class Codes: H04M 7/0093 signalling arrangements in networks
• CPC Class Codes: H04M 7/128 Details of addressing, directories or routing tables
• CPC Class Codes: H04W 92/02 Inter-networking arrangements

Abstract

A method, system and gateway device enables interworking between an IP-based network and a circuit-switched network. A first address information of a first connection end located in the circuit-switched network is routed in a trigger message from the IP-based network to a gateway control function. The first and second call legs are established in parallel towards the first connection end based on the first address information, and towards a second connection end located in the IP-based network based on a second address information obtained from the trigger message. A single connection between the two connection ends is then established by connecting the first and second call legs. Thereby, IP-based signaling functionality can be used to add capability for subscribers located in the CS domain to be invited into conferences or calls with subscribers located in an IP-based domain, e.g. the IMS domain.

Claims

1. A method for enabling interworking between an IP-based network and a circuit-switched network, said method comprising the steps of:

forwarding a first address information of a first connection end located in a circuit-switched network in a trigger message routed from an IP-based network to a gateway control function;

establishing a first call leg towards said first connection end based on said first address information;

establishing a second call leg towards a second connection end located in said IP-based network based on a second address information obtained from said trigger message; and

connecting said first and second call legs to form a single connection.

2. A method according to claim 1, wherein said forwarding step comprises forwarding said first address information in said trigger message comprising a Session Initiation Protocol Refer message.

3. A method according to claim 1 wherein said establishing a second call leg step is performed before said establishing a first call leg step.

4. A method according to claim 2, wherein said forwarding step comprises forwarding said first address information in said Refer message comprising said first address information in a Refer-to header and said second address information in a Referred-by header.

5. A method according to claim 1, wherein said forwarding step comprises forwarding said first address information comprising a Session Initiation Protocol Uniform Resource Indicator with telephone information.

6. A method according to claim 5, wherein said forwarding step comprises forwarding said first address information comprising a Telephony Uniform Resource Indicator.

7. A method according to claim 1, further comprising setting up a dial-in type of Session Initiation Protocol conferencing and adding a participant at said first connection end to a conference.

8. A method according to claim 1, further comprising using said gateway control function to represent said first connection end in said IP-based network and to setup a circuit-switched call towards said first connection end.

9. A method according to claim 8, wherein said step of establishing said second call leg comprises providing an inband indication to said first connection end during said establishment of said second call leg.

10. A method according to claim 8, further comprising providing an in-band indication by a media gateway function.

11. A method according to claim 1, further comprising requesting a subscriber identity from said first connection end and checking said first address information based on said requested subscriber identity.

12. A method according to claim 11, wherein said requesting step comprises requesting said subscriber identity comprising a Connected Line identity.

13. A method according to claim 1, wherein said connecting step comprises connecting user plane connections of said first and second call legs together in a media gateway function controlled by said gateway control function.

14. A method according to claim 1, wherein said connecting step comprises mapping said trigger message to an initial address message of said circuit-switched network.

15. A method according to claim 14, wherein said mapping step comprises mapping said initial address message comprising an Integrated Services Digital Network User Part Initial Address Message.

16. A gateway device for enabling interworking between an IP-based network and a circuit-switched network said gateway device being configured to receive from said IP-based network a trigger message comprising a first address information and a second address information, and in response to said trigger message establish a first call leg towards a first connection end located in said circuit-switched network, based on said first address information, and establish a second call leg towards a second connection end located in said IP-based network based on said second address information.

17. A device according to claim 16, wherein said gateway device is configured to establish a circuit-switched connection towards said first connection end, and to establish a new Session Initiation Protocol session towards said second connection end.

18. A device according to claim 17, wherein said gateway device is configured to establish said new Session Initiation Protocol session after having established said circuit-switched connection.

19. A device according to claim 17, wherein said gateway device is configured to establish said new Session Initiation Protocol session before having established said circuit-switched connection.

20. A device according to claim 16, wherein said gateway device is configured to connect the established first call leg to at least one of an in-band announcement and tone in order to notify a user at said first connection end of the intended connection setup.

21. A device according to claim 16, wherein said gateway device comprises an Media Gateway Control Function of an IP Multimedia Subsystem network.

22. A device according to claim 16, wherein said gateway device is configured to connect user plane connections of said first and second call legs together in a media gateway function.

23. A device according to claim 22, wherein said media gateway function comprises a Media Gateway Function of an IP Multimedia Subsystem network.

24. A network system for enabling interworking between different networks, said system comprising:

a circuit-switched network;

an IP-based network; and

a gateway device for enabling interworking between said circuit-switched network and said IP-based network.

25. A system according to claim 24, wherein said circuit-switched network comprises a Global System for Mobile Communication network.

26. A system according to claim 24, wherein said IP-based network comprises an IP Multimedia Subsystem network.

27. A gateway device for enabling interworking between an IP-based network and a circuit-switched network, said gateway device comprising:

receiving means for receiving a first address information of a first connection end located in a circuit-switched network in a trigger message;

first establishing means for establishing a first call leg towards said first connection end based on said first address information;

second establishing means for establishing a second call leg towards a second connection end located in said IP-based network based on a second address information obtained from said trigger message; and

connecting means for connecting said first and second call legs to form a single connection.

28. The device according to claim 27, further comprising representing means for using said gateway control function to represent said first connection end in said IP-based network and setting up means for setting up a circuit-switched call towards said first connection end.