Handoff system and method between a wireless LAN and mobile communication network

• US 20060045049A1
• Filed: 08/29/2005
• Published: 03/02/2006
• Est. Priority Date: 08/30/2004
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Lee, Sang-Do, Lee, Ji-Cheol, Lee, Sung-Won, Moon, Sang-Jun, Kong, Dong-Keon, Chung, Eun-Young, Baek, Hye-Won, Jung, Heung-Chul, Pyo, Jong-Bum
• Granted Patent: US 7,586,876 B2
• Time in Patent Office: Days
• US Class Current: 370/331
• CPC Class Codes: H04W 36/0011 for data sessions of end-to-end connection
• CPC Class Codes: H04W 36/14 Reselecting a network or an air interface
• CPC Class Codes: H04W 80/00 Wireless network protocols or protocol adaptations to wireless operation
• CPC Class Codes: H04W 80/04 Network layer protocols, e.g. mobile IP [Internet Protocol]
• CPC Class Codes: H04W 92/02 Inter-networking arrangements

Abstract

A method for performing a handoff between a wireless local area network (LAN) including an access router (AR) supporting an Internet protocol (IP) routing function and a mobile communication network including a packet data service node (PDSN) connected to a base station system (BSS), for supporting the IP routing function. An access terminal (AT) detects its movement from the wireless LAN to the mobile communication network, and exchanges information for tunneling between the AR and the PDSN, with the PDSN. The PDSN sets up a tunnel for packet delivery between the PDSN and the AR, and delivers packets to the AT through the set tunnel.

Claims

1. A method for performing a handoff between a wireless local area network (LAN) comprising an access router (AR) supporting an Internet protocol (IP) routing function and a mobile communication network comprising a packet data service node (PDSN) connected to a base station system (BSS) for supporting the IP routing function, the method comprising the steps of:

detecting, by an access terminal (AT), its movement from the wireless LAN to the mobile communication network;

exchanging, between the AT and the PDSN, information for tunneling between the AR and the PDSN;

establishing by the PDSN, a tunnel for packet delivery between the PDSN and the AR; and

delivering packets to the AT through the tunnel.

2. The method of claim 1, wherein the tunneling information delivered from the PDSN to the AT comprises a serving PDSN IP address, and a PDSN IP address used for a tunnel between the PDSN and the AR.

3. The method of claim 1, wherein the tunneling information delivered from the AT to the PDSN comprises an existing IP address used in the wireless LAN by the AT.

4. The method of claim 1, wherein the tunneling information is delivered through an exchange of an Internet protocol control protocol (IPCP) message between the AT and the PDSN.

5. The method of claim 3, wherein the tunneling information is delivered through an exchange of an Internet protocol control protocol (IPCP) message between the AT and the PDSN, and the IPCP message comprises a field for requesting establishment of a tunnel from the PDSN to the AR.

6. The method of claim 1, further comprising the steps of:

establishing a tunnel for packet delivery from the PDSN to the AR; and

delivering packets delivered from the AT to a correspondent node (CN) connected to an external IP network via the tunnel.

7. The method of claim 1, further comprising the step of:

releasing the tunnel through an exchange of an Internet protocol control protocol (IPCP) message with the PDSN if the AT no longer receives packets after the tunnel is set up.

8. A wireless communication system for performing handoff of an access terminal (AT) between a wireless local area network (LAN) comprising an access router (AR) supporting an Internet protocol (IP) routing function and a mobile communication network comprising a packet data service node (PDSN) connected to a base station system (BSS) for supporting the IP routing function, the system comprising:

the AT having a dual-mode function capable of accessing both the wireless LAN and the mobile communication network, for exchanging information for tunneling between the AR and the PDSN with the PDSN, when the AT moves from the wireless LAN to the mobile communication network; and

the PDSN for receiving the tunneling information from the AT, establishing a tunnel for packet delivery with the AR according to the received tunneling information, and delivering packets to the AT via the tunnel.

9. The wireless communication system of claim 8, wherein the tunneling information delivered from the PDSN to the AT comprises a serving PDSN IP address, and a PDSN IP address used for a tunnel between the PDSN and the AR.

10. The wireless communication system of claim 8, wherein the tunneling information delivered from the AT to the PDSN comprises an existing IP address used by the AT in the wireless LAN.

11. The wireless communication system of claim 8, wherein the tunneling information is delivered through an exchange of an Internet protocol control protocol (IPCP) message between the AT and the PDSN.

12. The wireless communication system of claim 10, wherein the AT delivers the tunneling information to the PDSN through an exchange of an Internet protocol control protocol (IPCP) message with the PDSN, and the IPCP message comprises a field for requesting establishment of a tunnel from the PDSN to the AR.

13. The wireless communication system of claim 8, wherein the PDSN delivers packets delivered from the AT to a correspondent node (CN) connected to an external IP network via the tunnel.

14. The wireless communication system of claim 8, wherein if the AT no longer receives packets after the tunnel is established, the AT releases the tunnel through an exchange of an IPCP message with the PDSN.

15. A method for performing a handoff between a wireless local area network (LAN) comprising an access router (AR) supporting an Internet protocol (IP) routing function and a mobile communication network comprising a packet data service node (PDSN) connected to a base station system (BSS) for supporting the IP routing function, the method comprising the steps of:

exchanging, by the AT, information for performing temporary tunneling between the PDSN and the AR, with the PDSN;

establishing, by the PDSN, a temporary tunnel for packet delivery between the PDSN and the AR;

after completion of the handoff, updating, by the PDSN, the temporary tunnel between the PDSN and the AR as a primary tunnel; and

delivering, by the PDSN, packets to the AT via the updated primary tunnel.

16. The method of claim 15, wherein the temporary tunneling information delivered from the PDSN to the AT comprises a serving PDSN IP address, a PDSN IP address used for a tunnel between the PDSN and the AR, and a tunneling protocol supported in the PDSN.

17. The method of claim 15, wherein the temporary tunneling information delivered from the AT to the PDSN comprises an existing IP address used by the AT in the wireless LAN.

18. The method of claim 15, wherein the temporary tunneling information is delivered through an exchange of an Internet protocol control protocol (IPCP) message between the AT and the PDSN.

19. The method of claim 17, wherein the temporary tunneling information is delivered from the AT to the PDSN through an exchange of an Internet protocol control protocol (IPCP) message between the AT and the PDSN, and the IPCP message comprises a field for requesting establishment of a temporary tunnel from the PDSN to the AR.

20. The method of claim 15, further comprising the steps of:

updating the regular tunnel for packet delivery from the PDSN to the AR; and

delivering packets delivered from the AT to a correspondent node (CN) connected to an external IP network via the updated regular tunnel.

21. A method for performing a handoff by an access terminal (AT) that moves between a wireless local area network (LAN) comprising an access router (AR) supporting an Internet protocol (IP) routing function and a mobile communication network comprising a packet data service node (PDSN) for supporting the IP routing function, the method comprising the steps of:

detecting movement of the AT from the wireless LAN to the mobile communication network;

exchanging information for tunneling between the PDSN and the AR, with the PDSN; and

if a tunnel for packet delivery between the PDSN and the AR is established, receiving packets via the set tunnel.

22. The method of claim 21, wherein the tunneling information delivered from the PDSN comprises a serving PDSN IP address, and a PDSN IP address used for a tunnel between the PDSN and the AR.

23. The method of claim 21, wherein the tunneling information delivered to the PDSN comprises an existing IP address used by the AT in the wireless LAN.

24. The method of claim 21, wherein the tunneling information is delivered through an exchange of an Internet protocol control protocol (IPCP) message with the PDSN.

25. The method of claim 23, wherein the tunneling information is delivered to the PDSN through an exchange of an Internet protocol control protocol (IPCP) message with the PDSN, and the IPCP message comprises a field for requesting establishment of a tunnel from the PDSN to the AR.

26. The method of claim 21, further comprising the steps of:

establishing a tunnel for packet delivery from the PDSN to the AR; and

delivering packets to a correspondent node (CN) connected to an external IP network via the set tunnel.

27. The method of claim 21, further comprising the step of:

if the AT no longer receives packets after the tunnel is established, releasing the tunnel through an exchange of an IPCP message with the PDSN.

28. A method for performing a handoff between an access terminal (AT) that moves from a wireless local area network (LAN) comprising an access router (AR) supporting an Internet protocol (IP) routing function, to a mobile communication network comprising a packet data service node (PDSN) for supporting the IP routing function, the method comprising the steps of:

exchanging information for temporary tunneling between the PDSN and the AR, with the PDSN;

if a temporary tunnel for packet delivery between the PDSN and the AR is established, sending a primary tunnel update request to the PDSN after completion of the handoff to the mobile communication network; and

if the temporary tunnel for packet delivery between the PDSN and the AR is updated as a primary tunnel, receiving packets via the updated regular tunnel.

29. The method of claim 28, wherein the temporary tunneling information delivered from the PDSN to the AT comprises a serving PDSN IP address, a PDSN IP address used for a tunnel between the PDSN and the AR, and a tunneling protocol supported in the PDSN.

30. The method of claim 28, wherein the temporary tunneling information delivered from the AT to the PDSN comprises an existing IP address used by the AT in the wireless LAN.

31. The method of claim 28, wherein the AT delivers the temporary tunneling information through an exchange of an Internet protocol control protocol (IPCP) message with the PDSN.

32. The method of claim 30, wherein the AT delivers the temporary tunneling information to the PDSN through an exchange of an Internet protocol control protocol (IPCP) message with the PDSN, and the IPCP message comprises a field for requesting establishment of a temporary tunnel from the PDSN to the AR.

33. The method of claim 28, further comprising the step of:

if a regular tunnel for packet delivery from the PDSN to the AR is updated, delivering packets to a correspondent node (CN) connected to an external IP network via the updated primary tunnel.

34. A handoff method between a wireless local area network (LAN) and a mobile communication network performed by a packet data service node (PDSN) in a wireless communication system for performing a handoff for an access terminal (AT) that moves between the wireless LAN comprising an access router (AR) supporting an Internet protocol (IP) routing function and the mobile communication network comprising the PDSN connected to a base station system (BSS) for supporting the IP routing function, the method comprising the steps of:

detecting movement of the AT from the wireless LAN to the mobile communication network;

exchanging information for tunneling from the PDSN and the AR, with the AT;

establishing a tunnel for packet delivery with the AR; and

delivering received packets to the AT via the tunnel.

35. The handoff method of claim 34, wherein the tunneling information delivered to the AT comprises a serving PDSN IP address, a PDSN IP address used for a tunnel between the PDSN and the AR, and a tunneling protocol supported in the PDSN.

36. The handoff method of claim 34, wherein the tunneling information delivered from the AT comprises an existing IP address used by the AT in the wireless LAN.

37. The handoff method of claim 34, wherein the tunneling information is delivered to the AT through an exchange of an Internet protocol control protocol (IPCP) message with the AT.

38. The handoff method of claim 36, wherein the tunneling information is received from the AT through an exchange of an Internet protocol control protocol (IPCP) message with the AT, and the IPCP message comprises a field for requesting establishment of a tunnel from the PDSN to the AR.

39. The handoff method of claim 34, further comprising the step of:

if a tunnel for packet delivery with the AR is established, delivering packets delivered from the AT to a correspondent node (CN) connected to an external IP network via the set tunnel.

40. The handoff method of claim 34, further comprising the step of:

if the AT no longer receives packets after the tunnel is established, releasing the tunnel through an exchange of an IPCP message with the AT.

41. A handoff method between a wireless local area network (LAN) and a mobile communication network performed by a packet data service node (PDSN) in a wireless communication system for performing a handoff of an access terminal (AT) that moves from the wireless LAN comprising an access router (AR) supporting an Internet protocol (IP) routing function to the mobile communication network comprising the PDSN for supporting the IP routing function, the method comprising the steps of:

exchanging information for temporary tunneling between the PDSN and the AR with the AT, and establishing a temporary tunnel for packet delivery with the AR according to the temporary tunneling information;

after completion of the handoff, updating the temporary tunnel between the PDSN and the AR as a primary tunnel; and

delivering packets to the AT via the updated primary tunnel.

42. The handoff method of claim 41, wherein the temporary tunneling information delivered to the AT comprises a serving PDSN IP address, a PDSN IP address used for a tunnel between the PDSN and the AR, and a tunneling protocol supported in the PDSN.

43. The handoff method of claim 41, wherein the temporary tunneling information delivered from the AT comprises an existing IP address used by the AT in the wireless LAN.

44. The handoff method of claim 41, wherein the temporary tunneling information is delivered to the AT through an exchange of an Internet protocol control protocol (IPCP) message with the AT.

45. The handoff method of claim 43, wherein the PDSN receives the temporary tunneling information from the AT through an exchange of an IPCP message with the AT, and an Internet protocol control protocol (IPCP) message comprises a field for requesting establishment of a temporary tunnel from the PDSN to the AR.

46. The handoff method of claim 41, further comprising the steps of:

updating the primary tunnel for packet delivery to the AR; and

delivering packets delivered from the AT to a correspondent node (CN) connected to an external IP network via the updated primary tunnel.