System and method for roaming between networks

• US 20060019659A1
• Filed: 07/05/2005
• Published: 01/26/2006
• Est. Priority Date: 07/02/2004
• Status: Active Grant

• Current Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Original Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Inventors: Rosenberg, Jonathan D., Beall, James C.
• Granted Patent: US 8,611,893 B2
• Time in Patent Office: Days
• US Class Current: 455/432.100
• CPC Class Codes: H04W 36/0022 for transferring data sessions between adjacent core network technologies
• CPC Class Codes: H04W 36/00224 between packet switched [PS] and circuit switched [CS] network technologies, e.g. circuit switched fallback [CSFB]
• CPC Class Codes: H04W 60/00 Affiliation to network, e.g. registration; Terminating affiliation with the network, e.g. de-registration
• CPC Class Codes: H04W 76/20 Manipulation of established connections
• CPC Class Codes: H04W 80/10 adapted for application session management, e.g. SIP [Session Initiation Protocol] connection management H04W76/00; arrangements for session management H04L67/14
• CPC Class Codes: H04W 88/06 adapted for operation in multiple networks or having at least two operational modes, e.g. multi-mode terminals
• CPC Class Codes: H04W 88/16 Gateway arrangements
• CPC Class Codes: H04W 92/02 Inter-networking arrangements

Abstract

A system and method for roaming between networks include determining a presence of a mobile unit by determining when the mobile unit leaves a first network and enters a second network, and routing one or more calls based on the presence of the mobile unit by offloading the one or more calls to the second network into which the mobile unit roams.

Claims

1. A method for roaming between networks, comprising:

determining a presence of a mobile unit by determining when the mobile unit leaves a first network and enters a second network;

routing one or more calls based on the presence of the mobile unit by offloading the one or more calls to the second network into which the mobile unit roams.

2. The method of claim 1, wherein the first network is a circuit-based network and the second network is a packet-based network.

3. The method of claim 1, wherein the first network is a packet-based network and the second network is a circuit-based network.

4. The method of claim 1, further comprising creating a state reflecting the presence of the mobile unit, wherein the state is used to determine over which network to route incoming calls.

5. The method of claim 4, further comprising:

receiving a notification that the mobile unit is available on the second network;

updating the state of the mobile unit based on the notification;

routing the incoming calls over the second network.

6. The method of claim 4, further comprising:

determining the presence of the mobile unit from the created state;

if the mobile unit is available on the second network, offloading call signaling through a signaling gateway function.

7. The method of claim 4, further comprising:

receiving a target phone number to establish a call;

determining in which network the target phone number is located;

routing the call to the target phone number.

8. The method of claim 1, further comprising converting a signaling message in a first protocol to a second protocol, wherein the second protocol is associated with a network receiving the signaling message.

9. The method of claim 1, further comprising:

determining whether to hand off a call;

transferring the call to a special number;

receiving a signaling message for the special number;

determining a network from which the mobile unit originates the call;

diverting the call to the network.

10. The method of claim 9, wherein diverting the call includes determining a call setup is occurring for the special number.

11. A computer readable medium including logic for roaming between networks, the logic operable to:

determine a presence of a mobile unit by determining when the mobile unit leaves a first network and enters a second network;

route one or more calls based on the presence of the mobile unit by offloading the one or more calls to the second network into which the mobile unit roams.

12. The computer readable medium of claim 11, wherein the first network is a circuit-based network and the second network is a packet-based network.

13. The computer readable medium of claim 11, wherein the first network is a packet-based network and the second network is a circuit-based network.

14. The computer readable medium of claim 11, the logic further operable to create a state reflecting the presence of the mobile unit, wherein the state is used to determine over which network to route incoming calls.

15. The computer readable medium of claim 14, the logic further operable to:

receive a notification that the mobile unit is available on the second network;

update the state of the mobile unit based on the notification;

route the incoming calls over the second network.

16. The computer readable medium of claim 14, the logic further operable to:

determine the presence of the mobile unit from the created state;

if the mobile unit is available on the second network, offload call signaling through a signaling gateway function.

17. The computer readable medium of claim 14, the logic further operable to:

receive a target phone number to establish a call;

determine in which network the target phone number is located;

route the call to the target phone number.

18. The computer readable medium of claim 11, the logic further operable to convert a signaling message in a first protocol to a second protocol, wherein the second protocol is associated with a network receiving the signaling message.

19. The computer readable medium of claim 11, the logic further operable to:

determine whether to hand off a call;

transfer the call to a special number;

receive a signaling message for the special number;

determine a network from which the mobile unit originates the call;

divert the call to the network.

20. The computer readable medium of claim 19, wherein diverting the call includes determining a call setup is occurring for the special number.

21. A system for roaming between networks, comprising:

a mobile unit operable to roam between a first network and a second network;

a Signal Transfer Point (STP) operable to;

determine a presence of the mobile unit by determining when the mobile unit leaves the first network and enters the second network;

route one or more calls based on the presence of the mobile unit by offloading the one or more calls to the second network into which the mobile unit roams.

22. The system of claim 21, wherein the first network is a circuit-based network and the second network is a packet-based network.

23. The system of claim 21, wherein the first network is a packet-based network and the second network is a circuit-based network.

24. The system of claim 21, wherein the STP is further operable to create a state reflecting the presence of the mobile unit, wherein the state is used to determine over which network to route incoming calls.

25. The system of claim 24, wherein the STP is further operable to:

receive a notification that the mobile unit is available on the second network;

update the state of the mobile unit based on the notification;

route the incoming calls over the second network.

26. The system of claim 24, wherein the STP is further operable to:

determine the presence of the mobile unit from the created state;

if the mobile unit is available on the second network, offload call signaling through a signaling gateway function.

27. The system of claim 24, wherein the STP is further operable to:

receive a target phone number to establish a call;

determine in which network the target phone number is located;

route the call to the target phone number.

28. The system of claim 21, further comprising a soft switch operable to convert a signaling message in a first protocol to a second protocol, wherein the second protocol is associated with a network receiving the signaling message.

29. A system for roaming between networks, comprising:

means for determining a presence of a mobile unit by determining when the mobile unit leaves a first network and enters a second network;

means for routing one or more calls based on the presence of the mobile unit by offloading the one or more calls to the second network into which the mobile unit roams.