EMERGENCY CALL HANDOFF BETWEEN HETEROGENEOUS NETWORKS

• US 20130017801A1
• Filed: 07/15/2011
• Published: 01/17/2013
• Est. Priority Date: 07/15/2011
• Status: Active Grant

• Current Assignee: Verizon Patent and Licensing Incorporated (Verizon Communications Inc.)
• Original Assignee: Verizon Patent and Licensing Incorporated (Verizon Communications Inc.)
• Inventors: SHAIKH, Imtiyaz
• Granted Patent: US 8,630,607 B2
• Time in Patent Office: Days
• US Class Current: 455/404.1
• CPC Class Codes: H04W 36/0066 of control information between different types of networks in order to establish a new radio link in the target network
• CPC Class Codes: H04W 36/12 Reselecting a serving backbone network switching or routing node
• CPC Class Codes: H04W 4/02 Services making use of location information
• CPC Class Codes: H04W 4/029 Location-based management or tracking services
• CPC Class Codes: H04W 4/90 Services for handling of emergency or hazardous situations, e.g. earthquake and tsunami warning systems [ETWS]
• CPC Class Codes: H04W 76/50 for emergency connections

Abstract

A system to receive, from a user device, a request to establish a communication session to allow an emergency call to be placed or transferred to a public safety access point (PSAP) server; determine whether the request includes a first indication that the emergency call is being initiated via the user device or a second indication that the emergency call is being handed off from a base station associated with another network device, place the emergency call, to the PSAP server and via a first gateway device associated with the network device, when the request includes the first indication; and transfer the emergency call, to the PSAP server and via a second gateway device associated with the other network device, when the request includes the second indication, where the second gateway device processed the emergency call prior to being handed off from the base station.

Claims

1. A method performed by a network device, the method comprising:

receiving, from a user device and via a first base station associated with a long term evolution (LTE) network, a request to establish a session associated with an emergency call;

determining whether the request includes a first indication that the emergency call is being initiated via the first base station or a second indication that the emergency call is being handed off from a second base station that is not associated with the LTE network;

connecting the emergency call, to a public safety access point (PSAP) server and via a first gateway device, when the request includes the first indication that the emergency call is being initiated by the user device; and

connecting the emergency call, to another PSAP server and via a second gateway device, when the request includes the second indication that the emergency call is being handed off from the second base station, where the second gateway device processes the emergency call prior to the emergency call being handed off by the first base station.

2. The method of claim 1, where the first indication is based on a non-access stratum (NAS) message that identifies the emergency call as being initiated by the user device.

3. The method of claim 1, where the second indication is based on a non-access stratum (NAS) message that identifies the emergency call as not being initiated by the user device or as being handed over from the second base station.

4. The method of claim 1, where forwarding the emergency call, to the other PSAP server and via the first base station and the second PGW, further includes:

retrieving context information associated with the user device, where the context information includes information, associated with the second gateway device; and

determining that the emergency call is to be forwarded by the second gateway device after being handed off to the first base station.

5. The method of claim 4, further comprising:

instructing a third gateway device to transfer the call to the second gateway device based on the determination that the emergency call is to continue to be processed by the second gateway device, where the third gateway device serves the first base station.

6. The method of claim 1, where connecting the emergency call, to a public safety access point (PSAP) server and via a first gateway device, further includes:

identifying to which PSAP server the emergency call is to be placed based on information associated with the first base station, via which the emergency call is initiated, or based on a location associated with the user device.

7. The method of claim 1, further comprising:

receiving an indication that the user device is to handoff the emergency call to a third base station that is not associated with the LTE network;

communicating with a third gateway device to determine that the emergency call can be handed over to the third base station, where the third gateway device serves the third base station; and

transmitting, to the third gateway device, an instruction to transfer the emergency call to the first gateway device based on the determination that the emergency call can be handed over to the third base station.

8. The method of claim 1, further comprising:

receiving an indication that the user device is to handoff the emergency call to a third base station that is not associated with the LTE network;

transmitting, to a third gateway device, a notification that the emergency call is to be handed off to the third base station, where the third gateway device serves the third base station; and

receiving, from the third gateway device, a request for context information associated with the user device, where the context information identifies via which gateway device to forward the emergency call; and

transmitting, to the third gateway device, information associated with the first gateway device, where transmitting the information associated with the first gateway device allows the third gateway device to transfer the call to the PSAP server via the first gateway device.

9. The method of claim 8, where the first base station corresponds to an evolved Node B device, where the second base station or the third base station correspond to an evolved high-rate packet data (eHRPD) device, or a wireless router device.

10. A network device comprising:

one or more processors to;

receive, from a user device, a request to establish a communication session to allow an emergency call to be placed or transferred to a public safety access point (PSAP) server,

determine whether the request includes a first indication that the emergency call is being initiated via the user device or a second indication that the emergency call is being handed off from a base station associated with another network device,

connect the emergency call, to the PSAP server and via a first gateway device associated with the network device, when the request includes the first indication; and

transfer the emergency call, to the PSAP server and via a second gateway device associated with the other network device, when the request includes the second indication, where the second gateway device processes the emergency call prior to being handed off from the base station.

11. The device of claim 10, where the other network device is associated with a long term evolution (LTE) network that is based on a Third Generation Partnership Project (3GPP) standard and where the network device is not associated with the LTE network.

12. The device of claim 11, where, when transferring the emergency call, to the PSAP server and via a second gateway device, the one or more processors are further to:

obtain, from the other network device, context information associated with the user device, where the context information identifies that the second gateway device processes the emergency call prior to being handed off from the base station.

13. The device of claim 11, where the first indication is based on a non-access stratum (NAS) message, which identifies the emergency call as being initiated by the user device, and

where the second indication is based on another NAS message that identifies the emergency call as not being initiated by the user device or as being handed over from the base station.

14. The device of claim 11, where, when placing the emergency call, the one or more processors are further to:

communicate with a further network device to determine whether the user device is authenticated, where the communication, with the further network, includes information associated with the user device,

place the call to the PSAP server via the first gateway based on a notification, received from the further network device, that the user device is authenticated, and

place the call to the PSAP server via a third gateway bases on another notification, received from the further network device, that the user device cannot be authenticated.

15. A system comprising:

one or more devices to;

receive, from a user device and via a first base station, a request to establish a communication session,

determine, in response to the request, whether the communication session is associated with an emergency call or a normal call,

establish the communication session to allow the call to be placed as a normal call when the request does not include an indication that the call is the emergency call,

establish the communication session, via the first base station and a first gateway device, to allow the call to be placed, as a first emergency call, when the request includes a first indication to place the call as the first emergency call, and

establish the communication session, via the first base station and a second gateway device, to allow the call to be handed off, as a second emergency call and from a second base station, when the request includes a second indication that the second emergency call is to be handed off,

where the second emergency call is established via the second gateway device.

16. The system of claim 15, where the second base station is associated with a long term evolution (LTE) network that is based on a Third Generation Partnership Project (3GPP) standard, and the first base station is not associated with the LTE network.

17. The system of claim 15, where the first base station is associated with a long term evolution (LTE) network that is based on a Third Generation Partnership Project (3GPP) standard, and the second base station is not associated with the LTE network.

18. The system of claim 15, where, when establishing the communication session, via the first base station and the second gateway device, the one or more processors are further to:

retrieve, from a server device, information that identifies the second gateway device as a device via which the second emergency call was initiated, and

transmit an instruction to transfer the second emergency call to the second gateway device based on the information that identifies the second gateway device.

19. The system of claim 15, where the first indication includes a non-access stratum (NAS) message, which indicates that the first emergency call is being initiated, and where the second indication includes another NAS message, which indicates that the second emergency call is being handed off.

20. The system of claim 15, where, when establishing the communication session, via the first base station and the first gateway device, the one or more devices are further to:

transmit, to a server device, information associated with the first base station or information associated with a location of the user device that allows the server device to identify a public safety access point (PSAP) server to which the first emergency call is to be placed,

receive, from the server device, information that identifies the PSAP server to which the first emergency call is to be placed, and

place the call, to the identified PSAP server, via the first base station and the first gateway device.