Method and system for providing handoff between mobile communication network and wireless local area network, and switching device therefor

• US 20060002355A1
• Filed: 07/05/2005
• Published: 01/05/2006
• Est. Priority Date: 07/05/2004
• Status: Abandoned Application

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Lee, Sang-Do, Lee, Sung-Won, Moon, Sang-Jun, Kong, Dong-Keon, Chung, Eun-Young, Baek, Hye-Won, Jung, Heung-Chul, Pyo, Jong-Bum
• Application Number:
  US11/173,158
• Publication Number:
  US 20060002355A1
• Time in Patent Office: Days
• US Class Current: 370/338
• CPC Class Codes: H04W 12/062 Pre-authentication
• CPC Class Codes: H04W 36/14 Reselecting a network or an air interface
• CPC Class Codes: H04W 36/32 by location or mobility data, e.g. speed data
• CPC Class Codes: H04W 60/00 Affiliation to network, e.g. registration; Terminating affiliation with the network, e.g. de-registration
• CPC Class Codes: H04W 8/26 Network addressing or numbering for mobility support
• CPC Class Codes: H04W 80/00 Wireless network protocols or protocol adaptations to wireless operation
• CPC Class Codes: H04W 84/042 Public Land Mobile systems, e.g. cellular systems
• CPC Class Codes: H04W 84/12 WLAN [Wireless Local Area Networks]

Abstract

A method and system for providing a handoff between a mobile communication network including a mobile switching center (MSC) and a home location register (HLR), and a wireless local area network (WLAN) including an access point (AP) and a voice over Internet protocol (VoIP) gateway to provide a VoIP service. The HLR registers therein subscriber information for the MT including an Internet protocol (IP) address of the AP. The MT transmits a handoff request to the MSC if the MT connected to the mobile communication network has moved to a region of the WLAN. The HLR transmits the subscriber information to the VoIP gateway. The AP allocates an IP address and a channel for WLAN access by the MT, and sets a session for a VoIP service of the MT.

Claims

1. A method for providing a handoff between a mobile communication network including a mobile switching center (MSC) for controlling call processing such that a circuit-switched voice service is provided to a mobile terminal (MT), and a home location register (HLR) in which subscriber information is registered, and a wireless local area network (WLAN) including an access point (AP) and a voice over Internet protocol (VoIP) gateway to provide a VoIP service, the method comprising the steps of:

(a) registering, by the AP, subscriber information for the MT comprising an Internet protocol (IP) address of the AP, in the HLR;

(b) transmitting, by the MT, a handoff request to the MSC if the MT connected to the mobile communication network has moved to a region of the WLAN;

(c) transmitting, by the HLR, the subscriber information to the VoIP gateway;

(d) allocating an IP address and a WLAN channel to the MT; and

(e) setting a session for a VoIP service of the MT.

2. The method of claim 1, wherein the subscriber information comprises information regarding the vocoder type of the MT.

3. The method of claim 1, further comprising the step of performing, by the VoIP gateway, subscriber authentication for the MT by transmitting predetermined pre-authentication information for the MT to the AP before channel allocation to the MT.

4. The method of claim 3, wherein the pre-authentication information comprises a medium access control (MAC) address, an international mobile subscriber identity (IMSI), and a mobile identification number (MIN) of the MT.

5. The method of claim 4, wherein the pre-authentication information further comprises a subscriber identity module (SIM).

6. The method of claim 4, wherein the pre-authentication information further comprises a network access identifier (NAI).

7. The method of claim 6, wherein the subscriber authentication for the MT is achieved by the AP by transferring subscriber information with the HLR via an authentication server.

8. The method of claim 7, wherein in step (e), the IP address of the MT is included in a predetermined authentication response message transmitted from the AP to the VoIP gateway based on the subscriber authentication.

9. The method of claim 1, wherein the step (e) comprises the steps of:

allocating, by the AP, an IP address for the MT;

transmitting, by the AP, the channel information to the VoIP gateway;

transmitting, by the VoIP gateway, the channel information to the MSC; and

transmitting, by the MSC, the channel information to the MT.

10. The method of claim 1, wherein the VoIP gateway comprises a wireless soft switch (WSS) for a VoIP service.

11. A system for providing handoff between a mobile communication network supporting a circuit-switched voice service to a mobile terminal (MT) and a wireless local area network (WLAN) supporting a voice over Internet protocol (VoIP)-based voice service, the system comprising:

an access point (AP) for allocating an Internet protocol (IP) address and a wireless channel used by the MT if the MT desires to access the WLAN;

a home location register (HLR) for registering therein predetermined subscriber information for the MT including an IP address of the AP;

a mobile switching center (MSC) for forwarding a handoff request message to the WLAN upon receiving the handoff request message from the MT; and

a switching device for, upon receiving the handoff request message from the MT, receiving the subscriber information from the HLR, performing a predetermined authentication process using the subscriber information, and performing a session connection for WLAN access by the MT.

12. The system of claim 11, wherein the switching device comprises an access gateway (AGW) for delivering the IP address of the AP to the HLR

13. The system of claim 12, wherein the switching device comprises a wireless soft switch (WSS) for receiving the subscriber information from the HLR during the handoff of the MT, and transmitting a request for the session connection to the AP.

14. The system of claim 13, wherein the switching device comprises a media gateway (MGW) for performing data conversion between a voice signal from the mobile communication network and a voice packet from the WLAN.

15. The system of claim 11, wherein the switching device receives channel information for WLAN access by the MT from the AP and delivers the channel information to the MSC;

wherein the MSC is designed such that the MSC delivers the received channel information to the MT.

16. The system of claim 11, wherein the switching device is designed such that upon receiving the subscriber information, the switching device performs the authentication process by transmitting predetermined pre-authentication information for the MT to the AP.

17. The system of claim 16, wherein the pre-authentication information comprises at least one of a medium access control (MAC) address, an international mobile subscriber identity (IMSI), and a mobile identification number (MIN) of the MT.

18. The system of claim 16, wherein the AP performs IP address and channel allocation for the MT after receiving the pre-authentication information for the MT and performing subscriber authentication using the pre-authentication information.

19. A switching device comprised in a wireless location area network (WLAN) that provides a voice over Internet protocol (VoIP) service to at least one mobile terminal (MT), the switching device comprising:

a wireless soft switch (WSS) for registering subscriber information for the MT comprising Internet protocol (IP) information of an access point (AP) for WLAN access by the MT in a home location register (HLR) of a mobile communication network, and upon receiving a handoff request of the MT from a mobile switching center (MSC) of the mobile communication network, performing a session connection for the MT using the subscriber information; and

a media gateway (MGW) connected to the WSS through a gateway control protocol, for performing data conversion between the mobile communication network and the WLAN.

20. The switching device of claim 19, wherein the WSS comprises an HLR interworking block for receiving, from the AP, an IP address registration message including a corresponding IP address and an international mobile subscriber identity (IMSI) and or a mobile identification number (MIN) of the MT, and delivering the received IP address registration message to the HLR.

21. The switching device of claim 19, wherein the WSS comprises a session initiation protocol (SIP) message processor for transmitting a call setup request message to the handoff requesting MT via the AP and receiving a response message from the MT in response to the call setup request message.

22. The switching device of claim 21, wherein the WSS comprises a MGW controller for exchanging a control signal for bearer connection/release with the MGW for call connection/release of the MT.

23. The switching device of claim 19, wherein the WSS is designed such that upon receiving the subscriber information, the WSS transmits predetermined pre-authentication information for the MT to the AP.

24. The switching device of claim 19, wherein WSS receives channel information for WLAN access by the MT from the AP and delivers the channel information to the MSC.