Supporting emergency calls on a wireless local area network

• US 20070032219A1
• Filed: 03/03/2006
• Published: 02/08/2007
• Est. Priority Date: 05/07/2004
• Status: Active Grant

• Current Assignee: Interdigital Technology Corporation (InterDigital, Inc.)
• Original Assignee: Interdigital Technology Corporation (InterDigital, Inc.)
• Inventors: Rudolf, Marian, Kwak, Joseph, Rahman, Shamim, Zuniga, Juan
• Granted Patent: US 8,682,279 B2
• Time in Patent Office: Days
• US Class Current: 455/404.100
• CPC Class Codes: H04W 12/06 Authentication
• CPC Class Codes: H04W 12/08 Access security
• CPC Class Codes: H04W 12/73 Access point logical identity
• 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 48/12 using downlink control channel
• CPC Class Codes: H04W 48/18 Selecting a network or a communication service
• CPC Class Codes: H04W 74/08 Non-scheduled access, e.g. ALOHA hybrid access H04W74/02
• CPC Class Codes: H04W 76/50 for emergency connections
• CPC Class Codes: H04W 84/12 WLAN [Wireless Local Area Networks]

Abstract

Several methods are provided for communicating emergency call capability information between a station and an access point (AP) in a wireless local area network. The methods include advertising by the AP of its emergency call capabilities and announcing by the station of its emergency call capabilities. The AP can advertise its emergency call capabilities in a beacon frame, a probe response frame, a reassociation response frame, or a reauthentication response frame. The station can announce its emergency call capabilities in an association request frame, a reassociation request frame, an authentication request frame, or a reauthentication request frame.

Claims

1. A method for supporting an emergency call in a wireless local area network, comprising the step of:

advertising by an access point (AP) of the emergency call capabilities of the AP.

2. The method according to claim 1, wherein the advertising step includes:

providing an indicator that the AP is capable of receiving an emergency call; and

providing parameters such that a station placing an emergency call can configure itself to communicate the emergency call to the AP.

3. The method according to claim 1, wherein the advertising step includes using a beacon frame to periodically transmit the emergency call capabilities of the AP.

4. The method according to claim 3, wherein the beacon frame includes an extendable capability information element that contains the emergency call capabilities of the AP.

5. The method according to claim 1, wherein the advertising step includes using a probe response frame to transmit the emergency call capabilities of the AP.

6. The method according to claim 1, wherein the advertising step includes using an association response frame to transmit the emergency call capabilities of the AP.

7. The method according to claim 1, wherein the advertising step includes using a reassociation response frame to transmit the emergency call capabilities of the AP.

8. The method according to claim 1, wherein the advertising step includes using an authentication response frame to transmit the emergency call capabilities of the AP.

9. The method according to claim 1, wherein the advertising step includes using a reauthentication response frame to transmit the emergency call capabilities of the AP.

10. A method for supporting an emergency call in a wireless local area network (WLAN), comprising the step of:

announcing by a station of the emergency call capabilities of the station to an access point (AP).

11. The method according to claim 10, wherein the announcing step includes using an information element to transmit the emergency call capabilities of the station.

12. The method according to claim 10, wherein the announcing step includes adding a bit flag to an existing information element to transmit the emergency call capabilities of the station.

13. The method according to claim 10, wherein the announcing step includes using an association request frame to transmit the emergency call capabilities of the station.

14. The method according to claim 10, wherein the announcing step includes using a reassociation request frame to transmit the emergency call capabilities of the station.

15. The method according to claim 10, wherein the announcing step includes using an authentication request frame to transmit the emergency call capabilities of the station.

16. The method according to claim 10, wherein the announcing step includes using a reauthentication request frame to transmit the emergency call capabilities of the station.

17. The method according to claim 10, further comprising the step of:

storing the emergency call capabilities of the station in a location accessible by any device on the WLAN.

18. The method according to claim 17, wherein the storing step permits interworking between the WLAN and other network types to support the emergency call.

19. A method for supporting an emergency call in a wireless local area network (WLAN), comprising the steps of:

initiating an emergency call by a station on the WLAN;

receiving the emergency call by an access point (AP) on the WLAN;

admitting the emergency call by the AP without requiring the station placing the emergency call to perform an authentication procedure required to admit other calls by the AP; and

providing the station with emergency call related settings to permit the station to access the WLAN.

20. The method according to claim 19, wherein the emergency call related settings include an emergency call access code.

21. The method according to claim 19, wherein the emergency call related settings include an emergency call security key.

22. A method for supporting an emergency call in a wireless local area network (WLAN), comprising the steps of:

initiating an emergency call by a station on the WLAN;

receiving the emergency call by an access point (AP) on the WLAN;

admitting the emergency call by the AP without requiring the station placing the emergency call to perform an authentication procedure required to admit other calls by the AP; and

routing the emergency call to an emergency call center.

23. The method according to claim 22, wherein the routing step includes performing semi-static routing whereby all emergency calls are routed to the emergency call center.

24. A method for supporting an emergency call in a wireless local area network (WLAN), comprising the steps of:

providing an emergency basic service set (BSS) identifier to a station, the emergency BSS identifier being used only for emergency calls; and

initiating an emergency call by the station, the emergency call including the emergency BSS identifier.

25. The method according to claim 24, wherein the providing step includes providing the emergency BSS identifier to the station in a probe response frame.

26. The method according to claim 24, wherein the providing step includes providing the emergency BSS identifier to the station in an association response frame.

27. The method according to claim 24, wherein the providing step includes providing the emergency BSS identifier to the station in a reassociation response frame.

28. A method for supporting an emergency call in a wireless local area network (WLAN), comprising the steps of:

initiating an emergency call by a station on the WLAN;

receiving the emergency call by an access point (AP) on the WLAN;

determining if the station has sufficient capabilities to complete the emergency call; and

having an element of the infrastructure network act as a proxy for the station if the station does not have sufficient capabilities to complete the emergency call.

29. The method according to claim 28, wherein the element of the infrastructure network includes a dedicated gateway node.

30. The method according to claim 28, further comprising the step of:

adding location information to the emergency call by the element of the infrastructure network.

31. The method according to claim 28, further comprising the step of:

monitoring traffic on the WLAN by the element of the infrastructure network, whereby the element of the infrastructure network learns the capability information of stations on the WLAN such that the element of the infrastructure network can act as a proxy for a station.