System for routing remote VoIP emergency calls

• US 20060072549A1
• Filed: 09/30/2004
• Published: 04/06/2006
• Est. Priority Date: 09/30/2004
• Status: Active Grant

• Current Assignee: WSOU Investments, LLC (WSOU Holdings, LLC)
• Original Assignee: Alcatel-Lucent USA, Inc. (Nokia Corporation)
• Inventors: Patfield, Kevin M., Goldman, Stuart Owen
• Granted Patent: US 7,894,406 B2
• Time in Patent Office: Days
• US Class Current: 370/352
• CPC Class Codes: H04M 11/04 with alarm systems, e.g. fire, police or burglar alarm systems
• CPC Class Codes: H04M 2242/04 for emergency applications
• CPC Class Codes: H04M 2242/14 with services dependent on location
• 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: H04M 7/1285 Details of finding and selecting a gateway for a particular call

Abstract

A method is provided for routing an emergency call from Customer Premises Equipment (CPE) to a Public Safety Answering Point (PSAP). The method includes: establishing a session over a packet-switched network (200) between a CPE (110) and a network node (302), such that the CPE (110) accesses a Public Switched Telephone Network (PSTN) (400) from the network node (302) via a telecommunications switch (500) associated with a first PSAP (320) serving a geographic region (300) different than where the CPE (110) is currently located; identifying a telephone number for a second PSAP (120) serving the geographic region (100) in which the CPE (110) is located; and, substituting the identified telephone number for a dialed telephone number when the dialed telephone number is indicative of an emergency call.

Claims

1. A method for routing an emergency call from Customer Premises Equipment (CPE) to a Public Safety Answering Point (PSAP), the method comprising:

(a) establishing a session over a packet-switched network between a CPE and a network node, such that the CPE accesses a Public Switched Telephone Network (PSTN) from the network node via a telecommunications switch associated with a first PSAP serving a geographic region different than where the CPE is currently located;

(b) identifying a telephone number for a second PSAP serving the geographic region in which the CPE is located;

(c) storing the identified telephone number for later use should an emergency call be placed; and

,

(d) substituting the identified telephone number for a dialed telephone number when the dialed telephone number is indicative of an emergency call.

2. The method of claim 1, further comprising:

registering the CPE with the network node; and

,

determining from the registration if the CPE is remote from the geographic region served by the first PSAP.

3. The method of claim 2, further comprising:

obtaining a Directory Number (DN) associated with the CPE'"'"'s location, said DN corresponding to a location within the geographic region served by the second PSAP.

4. The method of claim 3, wherein when the session established in step (a) is via dial-up access, a modern pool or a remote access server, the DN is obtained via caller-ID.

5. The method of claim 3, wherein when the session established in step (a) is at a non-local IP address, the DN is obtained from a local database relating ranges of IP addresses to example telephone numbers within the same geographical location as is served by a range of IP addresses.

6. The method of claim 3, wherein when the session established in step (a) is at a non-local IP address and a DN is not determined by the means described in claims 4 and 5, soliciting a local telephone number from the user via a dialog with the user.

7. The method of claim 3, wherein the identified PSAP telephone number in step (b) is obtained from a database relating DNs to the respective PSAP telephone numbers serving the geographic regions to which the DNs correspond.

8. The method of claim 2, further comprising:

maintaining a list of remote CPE register with the network node along with the PSAP telephone number identified for each registered CPE.

9. The method of claim 1, further comprising:

forwarding the identified PSAP telephone number to the CPE such that the CPE makes the substitution upon a user dialing an emergency telephone number.

10. The method of claim 1, wherein the substitution is made at the network node.

11. A system for routing an emergency call from Customer Premises Equipment (CPE) to a Public Safety Answering Point (PSAP), the system comprising:

means for establishing a session over a packet-switched network between a CPE and a network node, such that the CPE accesses a Public Switched Telephone Network (PSTN) from the network node via a telecommunications switch associated with a first PSAP serving a geographic region different than where the CPE is currently located;

means for identifying a telephone number for a second PSAP serving the geographic region in which the CPE is located; and

,

means for substituting the identified telephone number for a dialed telephone number when the dialed telephone number is indicative of an emergency call.

12. The system of claim 11, further comprising:

means for registering the CPE with the network node; and

,

means for determining from the registration if the CPE is remote from the geographic region served by the first PSAP.

13. The system of claim 12, further comprising:

means for obtaining a Directory Number (DN) associated with the CPE'"'"'s location, said DN corresponding to a location within the geographic region served by the second PSAP.

14. The system of claim 13, wherein when the session established is via dial-up access, a modern pool or a remote access server, the DN is obtained via caller-ID.

15. The system of claim 13, wherein the identified PSAP telephone number is obtained from a database relating DNs to the respective PSAP telephone numbers serving the geographic regions to which the DNs correspond.

16. The system of claim 12, further comprising:

means for maintaining a list of remote CPE registered with the network node along with the PSAP telephone number identified for each registered CPE.

17. The system of claim 11, further comprising:

means for forwarding the identified PSAP telephone number to the CPE such that the CPE makes the substitution upon a user dialing an emergency telephone number.

18. The system of claim 11, wherein the substitution is made at the network node.

19. The system of claim 11, wherein the packet-switched network is an Internet Protocol (IP) network.

20. The system of claim 19, wherein the network node comprises at least one of an IP gateway or a Private Branch eXchange (PBX).

21. The system of claim 11, wherein the network node comprises a Centrex supported on the telecommunications switch.

22. The system of claim 11, wherein the switch is a softswitch comprising the network node.