SS7 ISUP TO SIP BASED CALL SIGNALING CONVERSION GATEWAY FOR WIRELESS VOIP E911

• US 20160277586A1
• Filed: 05/27/2016
• Published: 09/22/2016
• Est. Priority Date: 04/04/2006
• Status: Abandoned Application

• Current Assignee: TeleCommunication Systems Inc (Comtech Telecommunications Corporation)
• Original Assignee: TeleCommunication Systems Inc (Comtech Telecommunications Corporation)
• Inventors: MITCHELL, DON
• Application Number:
  US15/167,207
• Publication Number:
  US 20160277586A1
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: H04L 12/66 Arrangements for connecting between networks having differing types of switching systems, e.g. gateways
• CPC Class Codes: H04L 65/1104 Session initiation protocol [SIP]
• CPC Class Codes: H04M 7/006 Networks other than PSTN/ISDN providing telephone service, e.g. Voice over Internet Protocol (VoIP) , including next generation networks with a packet-switched transport layer H04L65/00 takes precedence; aspects not specific to the type of network H04M3/00; special services in those networks H04M3/42
• CPC Class Codes: H04M 7/0066 Details of access arrangements to the networks where the access arrangement is a PSTN/ISDN access H04M7/122
• CPC Class Codes: H04W 4/90 Services for handling of emergency or hazardous situations, e.g. earthquake and tsunami warning systems [ETWS]

Abstract

An SS7-based call protocol conversion gateway that translates between circuit-switched SS7 protocols and session initiation protocol (SIP) oriented protocol, allowing an E911 call initiated over a switched network to be routed by a VoIP network. The SS7-based call protocol conversion gateway provides a PSAP with MSAG quality (street address) information about a VoIP dual mode phone user without the need for a wireless carrier to invest in building out an entire VoIP core. Thus, wireless carriers may continue signaling the way they are today, i.e., using the J-STD-036 standard for CDMA and GSM in North America, yet see benefits of a VoIP network core, i.e., provision of MSAG quality location data to a PSAP.

Claims

1. (canceled)

2. A call protocol conversion gateway comprising one or more computing devices, the call protocol conversion gateway having machine executable instructions causing the call protocol conversion gateway to:

receive Signaling System Number 7 (SS7) call signaling for a Voice over Internet Protocol (VoIP) call from a mobile switching center (MSC);

convert the SS7 call signaling into session initiation protocol (SIP) call signaling;

send the SIP call signaling to a VoIP positioning center (VPC);

receive routing information for the VoIP call from the VPC, the routing information including an emergency services query key (ESQK) and an emergency services routing number (ESRN);

determine routing elements for the VoIP call based on the routing information for the VoIP call, wherein the routing elements includes an emergency services routing key (ESRK) and a trunk select code for the VoIP call; and

send the routing elements for the VoIP call to the MSC.

3. The call protocol conversion gateway of claim 2, wherein:

the routing elements further include a Public Switched Telephone Network (PSTN) number for the VoIP call.

4. The call protocol conversion gateway of claim 3, wherein:

the PSTN number is a last routing option for the VoIP call.

5. The call protocol conversion gateway of claim 4, wherein:

the last routing option corresponds to a contingency routing number.

6. The call protocol conversion gateway of claim 4, wherein:

the last routing option corresponds to a routing number associated with a national call center.

7. The call protocol conversion gateway of claim 2, wherein:

the routing elements are Wireless E9-1-1 elements.

8. The call protocol conversion gateway of claim 7, wherein:

the routing information comprises National Emergency Number Association (NENA) i2 standard elements.

9. The call protocol conversion gateway of claim 2, wherein:

the VoIP call is a wireless 911 call.

10. The call protocol conversion gateway of claim 2, wherein:

the VoIP call originates from a local area network (LAN).

11. The call protocol conversion gateway of claim 10, wherein:

the VoIP call originates from a WiFi network operating on the LAN.

12. The call protocol conversion gateway of claim 2, wherein:

the converting includes translating the SS7 call signaling for the VOIP call into SIP INVITE parameters.

13. The call protocol conversion gateway of claim 12, wherein:

the SIP INVITE parameters includes a callback number for the VoIP caller.

14. The call protocol conversion gateway of claim 12, wherein:

the SIP INVITE parameters includes a TO field addressed to 911.

15. A method comprising:

converting Signaling System Number 7 (SS7) call signaling for a Voice over Internet Protocol (VoIP) call into session initiation protocol (SIP) call signaling;

receiving routing information for the VoIP call from a VoIP Positioning Center (VPC), the routing information including an emergency services query key (ESQK) and an emergency services routing number (ESRN);

determining routing elements for the VoIP call based on the routing information for the VoIP call, wherein the routing elements includes an emergency services routing key (ESRK) and a trunk select code for the VoIP call; and

sending the routing elements for the VoIP call to a Mobile Switching Center (MSC).

16. The method of claim 15, wherein:

the routing elements further include a Public Switched Telephone Network (PSTN) number for the VoIP call.

17. The method of claim 16, wherein:

the PSTN number is a last routing option for the VoIP call.

18. The call protocol conversion gateway of claim 15, wherein:

the routing elements are Wireless E9-1-1 elements.

19. A system comprising:

a mobile switching center (MSC) that receives a Voice over Internet Protocol (VoIP) call with Signal System Number 7 (SS7) signaling;

a gateway that;

converts the SS7 call signaling for the VoIP call to Session Initiated Protocol (SIP) call signaling;

receives routing information for the VoIP call from a VoIP Positioning Center (VPC), wherein the routing elements comprises National Emergency Number Association (NENA) i2 standard elements;

determines Wireless E 9-1-1 elements for the VoIP call based on the routing information for the VoIP call; and

sends the Wireless E 9-1-1 elements to the MSC.

20. The system of claim 19, wherein the E 9-1-1 elements include an emergency services routing key (ESRK) and a trunk select code for the VoIP call.