Method for listening to signal tone from a called party by a calling party during network interworking

• US 20070201663A1
• Filed: 02/16/2007
• Published: 08/30/2007
• Est. Priority Date: 05/29/2005
• Status: Active Grant

• Current Assignee: INVT SPE LLC (FIG LLC (d/b/a Fortress Investment Group LLC))
• Original Assignee: Huawei Technologies Co., Ltd. (Huawei Investment & Holding Co., Ltd.)
• Inventors: Shi, Youzhu
• Granted Patent: US 8,335,221 B2
• Time in Patent Office: Days
• US Class Current: 379/201.10
• CPC Class Codes: H04L 65/1016 IP multimedia subsystem [IMS]
• CPC Class Codes: H04L 65/103 in the network
• CPC Class Codes: H04L 65/104 in the network
• CPC Class Codes: H04L 65/1069 Session establishment or de-establishment
• CPC Class Codes: H04L 65/1095 Inter-network session transfer or sharing
• CPC Class Codes: H04L 65/1096 Supplementary features, e.g. call forwarding or call holding systems providing special services or facilities to telephony subscribers H04M3/42
• CPC Class Codes: H04M 3/42017 Customized ring-back tones
• CPC Class Codes: H04M 7/123 where the packet-switched network is an Internet Protocol Multimedia System-type network
• CPC Class Codes: H04M 7/129 Details of providing call progress tones or announcements

Abstract

A method for listening to signal tone from a called party by a calling party during network interworking. When the media gateway control unit receives an Address Complete message or Call Progress message from the circuit domain network, the media gateway control unit instructs a media gateway to open a media stream channel. If the received message carries an indicator indicating the called party is free, the media gateway control unit sends a Ringing response message to the packet core network; if the received message does not carry a indicator indicating the called party is free, the media gateway control unit sends a response message carrying indicator of failed call but successful media stream setup or a response message indicating failed call but successful media stream setup to the packet core network. With the method according to the embodiments of the present invention, the calling party may hear ring-back tone indicating successful call, or signal tone or voice announcement indicating failed call.

Claims

1. A method for listening to signal tone from a called party by a calling party during network interworking, wherein a packet core network is connected to a circuit domain network via a Media Gateway Control Unit and accesses a user terminal via a network access node,

the method comprising:

instructing a media gateway (MGW) to open a media stream channel when the media gateway control unit receives an Address Complete message or Call Progress message from the circuit domain network, and,

sending a ringing response message to the packet core network if the received message carries an indicator indicating the called party is free.

2. The method of claim 1, wherein, the instructing a media gateway to open a media stream channel is instructing a media gateway to establish a unidirectional connection.

3. The method of claim 2, further comprising:

opening the media stream channel when a media control device of the calling party receives the ringing response message.

4. The method of claim 1, further comprising:

sending a response message carrying an indicator of failed call but successful media stream setup or a response message indicating failed call but successful media stream setup to the packet core network when the media gateway control unit receives the Address Complete message or Call Progress message from the circuit domain network and the received message does not carry the indicator indicating the called party is free.

5. The method of claim 4, wherein, the indicator indicating the called party is free comprises at least one of:

a subscriber free indicator, an in-band information indicator, and a cause indicator.

6. The method of claim 3, wherein, the media control device of the calling party is at least one of a terminal of the calling party and a network access node of the calling party.

7. A method for listening to signal tone from a called party by a calling party during network interworking, wherein a packet core network is connected to a circuit domain network via a media gateway control unit,

the method comprising:

sending a response message carrying indicator of failed call but successful media stream setup or a response message indicating failed call but successful media stream setup to the packet core network when the media gateway control unit receives an Address Complete message or Call Progress message from the circuit domain network and the received message does not carry an indicator indicating the called party is free.

8. The method of claim 7, wherein, the indicator indicating the called party is free comprises at least one of a subscriber free indicator, an in-band information indicator, and a cause indicator.

9. A communication system, in which a calling party in a packet core network is able to hear signal tone from a called party in a circuit domain network during network interworking, comprising:

a network access node, providing registration, authentication and authentification services for a user terminal to access a packet core network and translating between SIP and other access protocols;

a call session control unit, providing call control, route switching, and other functions for a registered user which accesses the packet core network and triggering a call to a service control unit;

a service control unit, providing a variety of service logic control functions for the registered user which accesses the packet core network, and serving as the host execution environment for the services;

a media resource control unit, providing control functions of media resource request, application, and release for the registered user which accesses the packet core network;

a media gateway control unit, providing interworking control function for a call between the registered user in the packet core network and another user in the circuit domain network and translating between SIP and other call control protocols.

10. The communication system of claim 9, wherein, an interface is arranged between the network access node and the call session control unit, the interface is SIP or a customized internal interface.

11. The communication system of claim 9, wherein, an interface is arranged between the service control unit and the call session control unit, the interface is SIP or a customized internal interface.

12. The communication system of claim 9, wherein, an interface is arranged between the media resource control unit and the call session control unit, the interface is SIP or a customized internal interface.

13. The communication system of claim 9, wherein, an interface is arranged between the media gateway control unit and the call session control unit, the interface is SIP or a customized internal interface.