Emergency service call back to a ported number

• US 7,480,374 B2
• Filed: 01/16/2003
• Issued: 01/20/2009
• Est. Priority Date: 01/16/2003
• Status: Active Grant

• Current Assignee: RPX Corporation
• Original Assignee: Alcatel-Lucent USA, Inc. (Nokia Corporation)
• Inventors: Rollender, Douglas H.
• Primary Examiner(s): ADDY, THJUAN KNOWLIN
• Application Number:
  US10/345,168
• Publication Number:
  US 20040141607A1
• Time in Patent Office: 2,196 Days
• Field of Search: 379/207.02, 379/37, 379/45, 379/210.01, 379/46, 455/404.1, 455/404.2
• US Class Current: 379/210.01
• CPC Class Codes: H04M 2242/04 for emergency applications
• CPC Class Codes: H04M 3/229 Wire identification arrangements; Number assignment determination
• CPC Class Codes: H04M 3/42195 Arrangements for calling back a calling subscriber when the wanted subscriber ceases to be busy H04M3/48

Abstract

An emergency routing number (ELRN) is assigned to each switch in a wired communication network. When a switch of the wired communication network routes an emergency call to a Public Service Answering Point (PSAP), the switch sends the ELRN as the calling party number and provides the PSAP with a hardware identifier (HID). The HID identifies, at the switch, the landline connecting the switch to the wired phone initiating the emergency call. If the emergency call drops, the PSAP performs a call back using the ELRN as the called party number. The switch that routed the emergency call to the PSAP receives the call back. The PSAP also sends the HID to the switch. When a switch receives its ELRN as the called party number, the switch recognizes an emergency call back situation and routes the emergency call back on the landline identified by the HID.

Claims

1. A method for assigning an emergency routing number, comprising:

assigning an emergency routing number to a switch in a wired communication network for use as the calling party number of emergency calls routed to a Public Service Answering Point (PSAP) by the switch, the emergency routing number being such that a call routed to the switch including the emergency routing number as a called party number is recognized by the switch as an emergency call back based on the emergency routing number without retrieving an identifier of a mobile station; and

identifying a hardware identifier at the switch, the hardware identifier identifying the landline connecting the switch to the wired phone initiating an emergency call.

2. The method of claim 1, wherein the assigned emergency routing number is not portable.

3. A method for supplying information associated with an emergency call, comprising:

sending an emergency routing number and a hardware identifier to a Public Service Answering Point (PSAP), the emergency routing number being the emergency routing number of a switch in a wired communication network handling communication needs of a wired phone initiating an emergency call and being such that a call routed to the switch including the emergency routing number as a called party number is recognized by the switch as an emergency call back based on the emergency routing number without retrieving an identifier of a mobile station, and the hardware identifier identifying, at the switch, the landline connecting the switch to the wired phone initiating the emergency call.

4. An emergency call back method, comprising:

receiving, at a Public Service Answering Point (PSAP), an emergency routing number of a switch in a wired communication network handling communication needs of a wired phone initiating an emergency call, the emergency routing number being such that a call routed to the switch including the emergency routing number as a called party number is recognized by the switch as an emergency call back based on the emergency routing number without retrieving an identifier of a mobile station;

receiving a hardware identifier in association with the emergency routing number, the hardware identifier identifying, at the switch, the landline connecting the switch to the wired phone initiating the emergency call; and

initiating a call back to the wired phone at the PSAP by calling the emergency routing number when the emergency call made by the wired phone drops.

5. The method of claim 4, further comprising:

signaling the hardware identifier to the switch when initiating the call back.

6. The method of claim 5, wherein the signaling step sends the hardware identifier in a generic address parameter.

7. A method for routing a call, comprising:

receiving, at a switch of a wired communication network, a called party number and a hardware identifier associated with a call; and

routing the call on a landline associated with the hardware identifier when the called party number matches an emergency routing number assigned to the switch, the hardware identifier identifying, at the switch, the landline connecting the switch to the wired phone initiating an emergency call, the emergency routing number being such that a call routed to the switch including the emergency routing number as the called party number is recognized by the switch as an emergency call back based on the emergency routing number without retrieving an identifier of a mobile station.

8. The method of claim 7, wherein the receiving step receives the hardware identifier in a generic address parameter.

9. The method of claim 7, wherein the routing step is performed with priority over other tasks at the switch.

10. The method of claim 7, further comprising:

performing a process to validate the call; and

wherein

the routing step routes the call when the call is validated.

11. The method of claim 10, wherein the perform step comprises:

comparing a calling party number of the call to a list of valid calling party numbers; and

validating the call when the comparing step indicates that the calling party number of the call is on the list.

12. The method of claim 11, wherein the list is a list of Public Service Answering Point calling party numbers.

13. The method of claim 7, wherein the call is an emergency call back from a PSAP.

14. A method for handling an emergency call, comprising:

receiving a directory number of a wired phone in association with an emergency call from the wired phone;

storing, at a switch of a wired communication network, a hardware identifier in a mapping table in association with the directory number, the hardware identifier identifying at the switch the landline connecting the switch to the wired phone initiating the emergency call; and

sending an emergency routing number and the directory number to a Public Service Answering Point (PSAP), the emergency routing number being the emergency routing number of the switch in handling communication needs of a wired phone initiating an emergency call and being such that a call routed to the switch including the emergency routing number as a called party number is recognized by the switch as an emergency call back based on the emergency routing number without retrieving an identifier of a mobile station.

15. The method of claim 14, wherein the sending step sends the emergency routing number as the calling party number.

16. The method of claim 14, wherein the sending step signals the directory number of the wired phone to the PSAP in a generic address parameter.

17. A method for routing a call, comprising:

receiving, at a switch of a wired communication network, a called party number and a directory number associated with a call;

accessing a hardware identifier from a mapping table using the directory number when the called party number matches an emergency routing number assigned to the switch, the hardware identifier identifying, at the switch, the landline connecting the switch to the wired phone initiating the emergency call; and

routing the call on the landline associated with the hardware identifier when the called party number matches an emergency routing number assigned to the switch, the emergency routing number being such that a call routed to the switch including the emergency routing number as the called party number is recognized by the switch as an emergency call back based on the emergency routing number without retrieving an identifier of a mobile station.

18. The method of claim 17, wherein the receiving step receives the directory number in a generic address parameter.

19. The method of claim 17, wherein the routing step is performed with priority over other tasks at the switch.

20. The method of claim 17, further comprising:

performing a process to validate the call; and

wherein

the routing step routes the call when the call is validated.

21. The method of claim 20, wherein the performing step comprises:

comparing a calling party number of the call to a list of valid calling party numbers; and

validating the call when the comparing step indicates that the calling party number of the call is on the list.

22. The method of claim 21, wherein the list is a list of Public Service Answering Point calling party numbers.

23. The method of claim 17, wherein the call is an emergency call back from a PSAP.