Call flow system and method use in legacy telecommunication system

Abstract

A method of operating a network server, such as a mobile application gateway, connect devices on a cellular or carrier network with individual networks, such as enterprise voice and data networks or residential networks. The effects of the present invention are far reaching in terms of transferring effective call control from the cellular network into the control of the individual network, such as the enterprise, and enabling new business models for the purchase of cellular service from a public cellular carrier by an enterprise.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a block diagram of an independently managed and controlled wireless carrier network, and an independently managed corporate enterprise network;

FIG. 2 is a diagram of a conventional enterprise network gateway server connected to a wireless carrier network;

FIG. 3 is a diagram of a gateway server system accordingly to one preferred embodiment of the present invention;

FIG. 4A is a diagram of an enterprise data and voice network operably connected using the gateway server system using pure enterprise call control according to one preferred embodiment;

FIG. 4B is a diagram of an enterprise data and voice network operably connected using the gateway server system using split call control according to one preferred embodiment;

FIG. 5 depicts a network architecture according to another preferred embodiment using VoIP systems;

FIG. 6 is a call flow diagram for call origination according to one embodiment of the present invention;

FIG. 7 is a call flow diagram for effecting call delivery using VoIP system according to another preferred embodiment of the present invention;

FIG. 8 is a call flow diagram for effecting mobile termination using VoIP according to another preferred embodiment of the present invention;

FIG. 9 is a diagram of a network architecture for a Legacy (TDM) network according to another preferred embodiment of the present invention;

FIG. 10 is a diagram of a next generation IMS architecture that is backwards compatible with legacy cellular networks based on existing cellular protocols;

FIG. 11 is a diagram of a conventional legacy network architecture that does not support IM;

FIG. 12 depicts a Packet Engine according to another preferred embodiment of the present invention allowing a call server to detect DTMF digit events on the call path;

FIG. 13 depicts one embodiment of the Packet Engine consisting of a user space;

FIG. 14 depicts a Linux kernel module of the Packet Engine;

FIG. 15 depicts the current IMS standard definition;

FIG. 16 depicts one exemplary embodiment of the invention for IMS service;

FIG. 17 and FIG. 18 depict a gateway server carrier (GS-C) configured as an IMS standard-compliant SIP, and associated algorithm; and

FIG. 19 depicts an algorithm for receiving incoming calls on various lines that are to be directed to a subscribers mobile phone.

Claims

1. A method of operating a gateway server to facilitate a connection between an enterprise PBX and a wireless network in a legacy telecommunication system, comprising the steps of: a) the gateway server sending a registration request to the enterprise PBX for a Pilot Number.

2. The method as specified in claim 1 wherein the gateway server ensures there is a binding between the Pilot Number and the gateway server.

3. The method as specified in claim 1 wherein the enterprise PBX rejects the registration request.

4. The method as specified in claim 3 wherein the gateway server again attempts registration and provides a username and password to the enterprise PBX.

5. The method as specified in claim 4 wherein the enterprise PBX authenticates the gateway server.

6. A method of operating an enterprise network gateway server (GS-E) to facilitate a connection between a mobile terminal of a wireless network and a subscriber of an enterprise PBX, comprising the steps of: a) the gateway server serving the enterprise PBX; andb) the gateway server receiving and acting on triggers originating from the wireless network and operating as a SCP.

7. The method as specified in claim 6 wherein the trigger complies with GSM MAP, CAP, ANSI-41 and/or WIN.

8. The method as specified in claim 7 wherein the enterprise subscriber is subscribed to an “all origination” trigger.

9. The method as specified in claim 6 wherein the gateway server also operates as a SIP Back to Back User Agent (BBUA) and replaces original dialed digits.

10. The method as specified in claim 9 wherein the gateway server also operates as the SIP BBUA to modify to/from addressing.

11. The method as specified in claim 6 wherein an Origination Request is generated by an MSC visited by the mobile terminal, and the Origination Request is directed to a Home GS.

12. The method as specified in claim 11 wherein a SIP INVITE message is sent from a gateway server of the wireless network (GS-C) to the enterprise network gateway server (GS-E) for querying a Pilot Number.

13. The method as specified in claim 12 wherein the SIP INVITE message facilitates the relay of the dialed digits of the mobile terminal from the GS-C to the GS-E.

14. The method as specified in claim 13 wherein a 302 Moved Temporarily message is sent from the GS-E to the GS-C containing the Pilot Number.

15. The method as specified in claim 14 wherein an acknowledgement (ACK) is responsively sent from the GS-C to the GS-E.

16. The method as specified in claim 15 wherein a CONNECT response is sent from the SCP gateway server to the MSC.

17. The method as specified in claim 16 wherein a call is routed from the mobile terminal via PSTN to the enterprise PBX.

18. The method as specified in claim 17 wherein the enterprise PBX routes the call to the GS-E based on the pilot DN in the called number.

19. The method as specified in claim 18 wherein the GS-E replaces the pilot DN in the INVITE with the original dialed digits and routes the INVITE back to the enterprise PBX.

20. The method as specified in claim 19 wherein the enterprise PBX routes the call to the terminating subscriber.

21. A method of routing an incoming call to an enterprise PBX subscriber via a gateway server of an enterprise PBX, comprising the steps of: a) the GS-E registering a route with the gateway server for the subscriber;b) the enterprise PBX subsequently routing the incoming call to the subscriber; andc) the enterprise PBX extending a call leg to the gateway server when the enterprise PBX routes the call to the subscriber's registered routes.

22. The method as specified in claim 21 wherein the call leg is routed to the subscriber's wireless device simultaneously when the call is routed to the subscriber.

23. The method as specified in claim 22 wherein the GS-E allocates media resources for the wireless leg.

24. The method as specified in claim 23 wherein the GS-E sends an INVITE to GS-C in order to determine the correct Temporary Local Directory Number (TLDN) or the wireless device.

25. The method as specified in claim 24 where in the GS-C retrieves the TLDN from an HLR in the wireless network and sends it back to the GS-E.

26. The method as specified in claim 25 where in the GS-E forwards the call to the wireless network via the enterprise PBX.

27. The method as specified in claim 26 wherein the call is answered by either the subscriber's desk phone or the subscriber's wireless device.

28. The method as specified in claim 27 wherein the subscriber is enabled to determine how the call is answered.