Method of and apparatus for use in forwarding calls intended for roaming subscriber units

• US 6,996,396 B1
• Filed: 12/30/1999
• Issued: 02/07/2006
• Est. Priority Date: 12/30/1999
• Status: Expired due to Fees

• Current Assignee: AT&T Mobility II LLC (AT&T, Inc.)
• Original Assignee: Cingular Wireless II LLC (AT&T, Inc.)
• Inventors: Snapp, John Lawrence
• Primary Examiner(s): Appiah, Charles N.
• Assistant Examiner(s): Ly, Nghi H.
• Application Number:
  US09/476,461
• Time in Patent Office: 2,231 Days
• Field of Search: 455/422, 455/426, 455/412, 455/432, 455/433, 455/445, 455/461, 455/414, 455/417, 455/560, 455/422.1, 455/426.1, 455/412.1, 455/432.1, 455/414.1
• US Class Current: 455/417
• CPC Class Codes: H04M 2207/18 wireless networks
• CPC Class Codes: H04M 3/533 Voice mail systems
• CPC Class Codes: H04M 3/54 Arrangements for diverting calls for one subscriber to another predetermined subscriber based on the calling party profile H04M3/42059; based on location H04M3/42348; based on presence H04M3/42365; to voice mail H04M3/53308
• CPC Class Codes: H04W 4/16 Communication-related supplementary services, e.g. call-transfer or call-hold
• CPC Class Codes: H04W 76/30 Connection release
• CPC Class Codes: H04W 92/02 Inter-networking arrangements
• CPC Class Codes: H04W 92/24 between backbone network devices

Abstract

A method for use in forwarding a call intended for a GSM-roaming subscriber unit (106) is performed by a mobility gateway (102) connected between an ANSI-41 network and a GSM network. The method includes associating the roaming subscriber unit (106) with one of a plurality of temporary transfer-to telephone numbers homed on a mobile switching center (118). The temporary transfer-to telephone number is used for an intermediate and temporary transfer of a call intended for the roaming subscriber unit (106) in response to some predetermined condition, such as a busy indication or expiration of time. This number is used to facilitate both the forwarding of the call to a voice mail system (116) and the tearing down of international long-distance connections.

Claims

1. A method for use in a mobility gateway for forwarding a call directed to a roaming subscriber unit, the method comprising:

storing in memory, at the mobility gateway coupled between a GSM network and an ANSI-41 based network, a plurality of temporary transfer-to telephone numbers;

selecting, for association with the roaming subscriber unit, one of the temporary transfer-to telephone numbers;

sending a message having the temporary transfer-to telephone number to a mobile switching center serving the roaming subscriber unit;

after selecting and sending, receiving, and storing information related to a call request for the roaming subscriber unit; and

after receiving and storing, receiving a location request message from a mobile switching center which homes the temporary transfer-to telephone number.

2. The method according to claim 1, wherein the temporary

transfer-to telephone number is homed on a mobile switching center that is different from a mobile switching center serving the roaming subscriber unit.

3. The method according to claim 1, further comprising:

associating the location request message with the call request for the roaming subscriber unit.

4. The method according to claim 3, further comprising:

after associating, sending a redirection request message to a gateway mobile switching center which received the call request.

5. The method according to claim 1, further comprising:

associating the location request message with the call request for the roaming subscriber unit based at least in part on the temporary transfer-to telephone number.

6. A mobility gateway for use in connection between an ANSI-41-based network and a GSM-based network, the mobility gateway comprising:

a processor;

memory for storing a plurality of temporary transfer-to telephone numbers homed on one or more mobile switching centers (MSCs) that is different from a mobile switching center serving a roaming subscriber unit;

said processor being operative for;

selecting one of the plurality of temporary transfer-to telephone numbers for association with the roaming subscriber unit;

sending a message having the temporary transfer-to telephone number to a GSM MSC serving the roaming subscriber unit;

after selecting and sending, receiving and storing information related to a call request for the roaming subscriber unit; and

after receiving and storing, receiving a location request message from an MSC which homes the temporary transfer-to telephone number.

7. The mobility gateway according to claim 6, wherein the selected temporary transfer-to telephone number associated with the roaming subscriber unit is homed on an ANSI-41 MSC different from a GSM MSC serving the roaming subscriber unit.

8. The mobility gateway according to claim 6, wherein said processor is further operative for:

associating the location request message with the call request for the roaming subscriber unit.

9. The mobility gateway according to claim 8, wherein said processor is further operative for:

after associating, sending a redirection request message to an ANSI gateway MSC Which received the call request.

10. The mobility gateway according to claim 6, wherein said processor is further operative for:

associating the location request message with the call request for the roaming subscriber unit based at least in part on the temporary tansfer-to telephone number.

11. A method for use in forwarding a call between an ANSI-41 based network and a GSM-based network intended for a subscriber unit, comprising:

receiving and storing information related to a call request for a roaming subscriber unit;

after receiving and storing, receiving a location request message from a mobile switching center which homes a temporary transfer-to telephone number associated with the roaming subscriber unit;

after receiving a location request message from a mobile switching center, correlating the message with a previous request message received by a mobility gateway;

associating the location request message with the call request for the roaming subscriber unit; and

after associating, sending a redirection request message to a gateway mobile switching center which received the call request for the roaming subscriber unit.

12. The method according to claim 11, further comprising, prior to receiving and storing the information related to the call request:

selecting the temporary transfer-to telephone number for association with a roaming subscriber unit; and

sending a message having the temporary transfer-to telephone number to a mobile switching center serving the roaming subscriber unit.

13. The method according to claim 11, further comprising:

wherein the receiving and storing of information related to the call request includes receiving and storing information comprising subscriber identification information and call identification information; and

wherein sending the redirection request message includes sending the call identification information.

14. The method according to claim 11, further comprising:

wherein receiving the location request message comprises receiving the temporary transfer-to telephone number; and

wherein associating the location request message with the call request comprises associating based on the temporary transfer-to telephone number.

15. A method for use in a mobility gateway coupled between an ANSI-41 based network and a GSM-based network, comprising:

selecting a temporary transfer-to telephone number for association with a roaming subscriber unit;

sending a message having the temporary transfer-to telephone number to a mobile switching center serving the roaming subscriber unit;

after selecting and sending, receiving and storing information related to a call request for the roaming subscriber unit;

after receiving and storing, receiving a location request message from a mobile switching center which homes the temporary transfer-to telephone number;

after receiving a location request message from a mobile switching center, correlating the message with a previous request message received by a mobility gateway;

associating the location request message with the call request for the roaming subscriber unit; and

after associating, sending a redirection request message to a gateway mobile switching center which received the call request for the roaming subscriber unit.

16. The method according to claim 15, further comprising:

wherein the receiving and storing of information related to the call request includes receiving and storing information comprising subscriber identification information and call identification information; and

wherein sending the redirection request message includes sending the call identification information.

17. The method according to claim 15, wherein the mobile switching center serving the roaming subscriber unit comprises a GSM mobile switching center and the gateway mobile switching center comprises an ANSI gateway mobile switching center.