Method and apparatus for interconnecting a private cellular network to a public cellular network

• US 7,688,790 B1
• Filed: 04/23/2004
• Issued: 03/30/2010
• Est. Priority Date: 09/29/1999
• Status: Active Grant

• Current Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Original Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Inventors: Sayers, Ian Leslie, Long, Paul Jan
• Primary Examiner(s): Patel; Jayanti K
• Assistant Examiner(s): ZHU, BO HUI ALVIN
• Application Number:
  US10/831,408
• Time in Patent Office: 2,167 Days
• Field of Search: 370/328, 370/338, 370/352, 370/356, 370/389, 455/432.1, 455/433, 455/560
• US Class Current: 370/338
• CPC Class Codes: H04W 84/045 using private Base Stations, e.g. femto Base Stations, home Node B
• CPC Class Codes: H04W 88/16 Gateway arrangements
• CPC Class Codes: H04W 92/02 Inter-networking arrangements

Abstract

A communications system extends over a cellular region formed of a plurality of wireless cells where each cell covers a portion of the cellular region. Each cell has a station which is responsible for communication with the cellular subscriber. In order to for the call to be properly managed in the public cellular domain, responsibility for call handling and processing must first be managed by the public MSC. Call handling with the public MSC for a private cellular subscriber first requires the exchange of information between the two systems. This is facilitated through the exchange of MAP and A interface signaling between the private and public cellular systems. Since this information on the private network is normally transmitted via IP, this information must be converted to standard SS7 based MAP and A protocol signaling in order for the public MSC to process.

Claims

1. A communication system, comprising:

one or more public networks supporting a first communication protocol, each public network comprising;

a public wired network operable to support communication with one or more public network cells of the public network according to the first communication protocol;

a base station sub-system (BSS) operable to communicate with mobile stations wirelessly through one or more base stations; and

a base station controller (BSC) operable to facilitate communication between the public wired network and the station sub-system; and

one or more private networks supporting a second communication protocol, wherein the second communication protocol is a packet-based protocol, each private network comprising;

a private wired local area network (LAN) operable to support communication with one or more private network cells of the private network according to the second communication protocol; and

a plurality of private network stations, each private network station operable to communicate with mobile stations located within a geographic area associated with the station;

an interworking unit operable to;

receive a first update request formatted in accordance with the first communication protocol, the first update request comprising a mobile station identifier identifying a mobile station in communication with one of the base stations;

identify a gatekeeper associated with the mobile station identifier; and

transmit a second update request to the identified gatekeeper, wherein the second update request is formatted in accordance with the second communication protocol and comprises the mobile station identifier and an address for communicating with the mobile station in accordance with the first communication protocol; and

the identified gatekeeper operable to;

receive the second update request from the interworking unit; and

associate the mobile station identifier with the address for communicating with the mobile station in accordance with the first communication protocol.

2. The communication system of claim 1, wherein the public wired network is operable to support the first communication protocol by supporting a first wired packet-based protocol.

3. The communication system of claim 1, wherein one or more of the private network stations is further operable to communicate wirelessly with the mobile station using a first packet-based protocol.

4. The communication system of claim 1, wherein one or more of the gatekeepers include a database for associating mobile station identifiers with addresses of the first communication protocol.

5. The communication system of claim 1, wherein the interworking unit comprises:

a first stack operable to process communication received according to the first protocol;

a second stack operable to process communication received according to the second protocol; and

a protocol converter operable to convert communication received according to the first communication protocol to communication for transmission according to the second communication protocol.

6. The communication system of claim 5, wherein the first stack includes a Message Transfer Part (MTP) layer, a Signaling Connection Control Part (SCCP) layer, and a Transactional Capabilities Application Part (TCAP) layer for an Signaling System 7 (SS7) protocol and wherein the second stack includes an Internet Protocol (IP) layer and a Transport Control Protocol (TCP)/User Datagram Protocol (UDP) layer.

7. The communication system of claim 1, wherein each gatekeeper comprises:

a local database operable to communicate according to Internet Protocol (IP) and operable to authenticate the mobile station;

a local client operable to communicate with a remote protocol gateway; and

a local interface operable to communicate with the interworking unit.

8. The communication system of claim 1, wherein each gatekeeper comprises an H.323 database for associating mobile station identifiers with Signaling System #7 (SS7) addresses.

9. The communication system of claim 1, further comprising a gateway operable to transmit communication between one or more of the private networks and an external network, the external network supporting communication according to a third communication protocol.

10. The communication system of claim 9, wherein the external network comprises one or more of a Public Switched Telephone Network (PSTN), an Integrated Services Digital Line (ISDN), and a Public Land Mobile Network (PLMN).

11. The communication system of claim 1, wherein a portion of one or more of the private network cells overlap a portion of one or more of the public network cells.

12. A communication system, comprising:

a first network operable to support a first communication protocol, the first network including a first station operable to communicate wirelessly with a mobile station;

a second network operable to support a second communication protocol, wherein the second network comprises one or more local area networks (LANs) and the second communication protocol is a packet-based protocol, the second network coupled to the first network and including a second station operable to communicate wirelessly with the mobile station;

an interworking unit operable to;

receive a first update request from the first network formatted in accordance with the first communication protocol, the first update request comprising a mobile station identifier identifying a mobile station in communication with the first network; and

identify a gatekeeper in the second network associated with the mobile station identifier; and

transmit a second update request to the identified gatekeeper, the second update request formatted in accordance with the second communication protocol and comprising the mobile station identifier and a first address associated with the first network, wherein the first address comprises an address associated with the first communication protocol; and

the identified gatekeeper operable to;

receive the second update request from the interworking unit; and

associate the mobile station identifier with the first address.

13. The communication system of claim 12, wherein the first network is operable to support a first communication protocol by supporting a first packet-based wired protocol.

14. The communication system of claim 12, wherein the first station is further operable to communicate wirelessly with the mobile station using a first packet-based wireless protocol.

15. The communication system of claim 12, wherein the first network comprises a public network and wherein the second network comprises a private network.

16. The communication system of claim 12, wherein the interworking unit comprises:

a first stack operable to process communication received according to the first protocol;

a second stack operable to process communication received according to the second protocol; and

a protocol converter operable to convert communication between the first communication protocol and the second communication protocol.

17. The communication system of claim 16, wherein the first stack includes a Message Transfer Part (MTP) layer, a Signaling Connection Control Part (SCCP) layer, and a Transactional Capabilities Application Part (TCAP) layer for a Signaling System 7 (SS7) protocol, and wherein the second stack includes an Internet Protocol (IP) layer and a Transport Control Protocol (TCP)/User Datagram Protocol (UDP) layer.

18. The communication system of claim 12, wherein the gatekeeper comprises:

a local database operable to communicate according to Internet Protocol (IP) and operable to authenticate the mobile station;

a local client operable to communicate with a remote protocol gateway; and

a local interface operable to communicate with the interworking unit.

19. The communication system of claim 12, wherein the gatekeeper includes a database operable to associate mobile station identifiers with addresses of the first communication protocol.

20. The communication system of claim 19, wherein the database comprises an H.323 database for associating mobile station identifiers with Signaling System #7 (SS7) addresses.

21. The communication system of claim 12, further comprising a gateway operable to transmit communication between the second network and a third network, the third network supporting communication according to a third communication protocol.

22. The communication system of claim 21, wherein the third network comprises one or more of a Public Switched Telephone Network (PSTN), an Integrated Services Digital Line (ISDN), and a Public Land Mobile Network (PLMN).

23. The communication system of claim 12, wherein the first network comprises a public wireless network.

24. The communication system of claim 12, wherein the first network comprises a private wireless network.

25. The communication system of claim 12, wherein the first station is further operable to provide communication service to a first cell area, and wherein the second station is further operable to provide communication service to a second cell area, and wherein at least a portion of the second cell area overlaps at least a portion of the first cell area.

26. A method for providing communication, comprising:

receiving information wirelessly at a first station from a mobile station, wherein the information received includes a mobile station identifier associated with the mobile station;

transmitting at least a portion of the information to an interworking unit over a first network according to a first communication protocol;

identifying a gatekeeper associated with the mobile station identifier;

transmitting at least a portion of the information and an address associated with the first communication protocol to the identified gatekeeper according to a second communication protocol, wherein the second communication protocol comprises a packet-based protocol;

receiving, at the identified gatekeeper, at least a portion of the information and the address associated with of the first communication protocol;

associating the mobile station identifier with the address associated with the first communication protocol; and

communicating with the mobile station over the first network using the address associated with the mobile station identifier.

27. The method of claim 26, wherein transmitting information over a first network according to a first communication protocol comprises communicating information according to a first packet-based wired protocol.

28. The method of claim 26, wherein receiving information wirelessly at the first station comprises receiving information according to a first packet-based wireless protocol.

29. The method of claim 26, wherein transmitting information over the first network comprises transmitting information over a private network and wherein communicating over a second network comprises communicating over a public network.

31. The method of claim 26, wherein associating the mobile station identifier with the address of the first communication protocol comprises associating the mobile station identifier with a Signaling System #7 (SS7) address in an H.323 database.

30. The method of 26, further comprising:

authenticating the mobile station using a local database operable to communicate according to Internet Protocol (IP);

communicating with a remote protocol gateway using a local client operable; and

communicating with the interworking unit using a local interface.