HANDOVER BETWEEN AN IEEE 802.16 WiBro NETWORK AND A UMTS NETWORK USING MEDIA INDEPENDENT HANDOVER FUNCTION

• US 20080198804A1
• Filed: 09/27/2007
• Published: 08/21/2008
• Est. Priority Date: 02/16/2007
• Status: Active Grant

• Current Assignee: Interdigital Technology Corporation (InterDigital, Inc.), SK Telecom Co., Ltd.
• Original Assignee: Interdigital Technology Corporation (InterDigital, Inc.)
• Inventors: Kim, Hyun Wook, Hossain, Khalid Shamsuddin, Rahman, Shamim Akbar, Perras, Michelle, Boutin, Jean-Ian, Cho, Yong Sun, Eoh, Suan
• Granted Patent: US 7,894,400 B2
• Time in Patent Office: Days
• US Class Current: 370/331
• CPC Class Codes: H04W 36/0019 adapted for mobile IP [MIP]
• CPC Class Codes: H04W 36/005 involving radio access media independent information, e.g. MIH [Media independent Hand-off]
• CPC Class Codes: H04W 36/302 due to low signal strength
• CPC Class Codes: H04W 80/04 Network layer protocols, e.g. mobile IP [Internet Protocol]
• CPC Class Codes: H04W 88/06 adapted for operation in multiple networks or having at least two operational modes, e.g. multi-mode terminals

Abstract

A wireless transmit/receive unit (WTRU) may include an IEEE 802.16 modem, a universal mobile telecommunication system (UMTS) modem and a media independent handover (MIH) entity. Software application programming interfaces provide the MIH entity with mechanisms to receive information about IEEE 802.16 and UMTS links, control IEEE 802.16 and UMTS modems for handover, discover an MIH server and IP multimedia system nodes, trigger mobile IP handover, etc. If an IEEE 802.16 link has been successfully established, the MIH entity starts an MIH session. When the IEEE 802.16 modem indicates that a connection is going to be terminated, the MIH entity activates the UMTS modem for handover. If the IEEE 802.16 modem indicates that a link parameter has crossed a threshold, the MIH entity sends IEEE 802.16 and WCDMA signal measurements to an MIH server. After receiving an MIH switch request, the MIH entity initiates handover to the UMTS network.

Claims

1. A method implemented in a wireless transmit/receive unit (WTRU) for performing handover between an IEEE 802.16 network and a universal mobile telecommunication system (UMTS) network using IEEE 802.21 media independent handover (MIH) functions, the method comprising:

an MIH entity requesting an IEEE 802.16 modem to establish an IEEE 802.16 link via a first application programming interface (API);

the IEEE 802.16 modem reporting a status of an attempt to establish an IEEE 802.16 link to the MIH entity via a second API;

if the status indicates that an IEEE 802.16 link has been successfully established, the MIH entity starting an MIH session;

the IEEE 802.16 modem indicating that a layer 2 connection is expected be terminated in a certain time interval via a third API to the MIH entity; and

the MIH entity activating a UMTS modem for handover.

2. The method of claim 1 further comprising:

the MIH entity requesting a discovery of a foreign agent (FA) and mobile Internet protocol (IP) binding update; and

the IEEE 802.16 modem performing a discovery of an FA and mobile IP binding update via an Internet protocol (IP) stack of the WTRU over the IEEE 802.16 link.

3. The method of claim 2 further comprising:

the MIH entity requesting a discovery of a proxy call state control function (P-CSCF) and an MIH server; and

the IEEE 802.16 modem performing a discovery of a P-CSCF and an MIH server via the IP stack over the IEEE 802.16 link.

4. The method of claim 3 wherein the MIH server is discovered via one of dynamic host configuration protocol (DHCP) and domain name system (DNS).

5. The method of claim 3 further comprising:

the MIH entity requesting IP multimedia subsystem (IMS) registration; and

the IEEE 802.16 modem performing IMS registration via the IP stack over the IEEE 802.16 link.

6. The method of claim 5 further comprising:

the MIH entity requesting a home agent (HA) IP address; and

the IEEE 802.16 modem performing HA IP address query via the IP stack over the IEEE 802.16 link.

7. The method of claim 1 wherein the MIH entity uses an AT+CFUN command to activate the UMTS modem.

8. The method of claim 1 further comprising:

the MIH entity setting a threshold via a Link_Configure_Thresholds.request API for an IEEE 802.16 link parameter which when crossed triggers generation of a measurement report; and

the IEEE 802.16 modem indicating a result of the configuration to the MIH entity via a Link_Configure_Thresholds.confirm API.

9. The method of claim 8 further comprising:

the IEEE 802.16 modem indicating that the IEEE 802.16 link parameter has crossed the threshold to the MIH entity via a Link_Parameter_Report.indication API.

10. The method of claim 9 further comprising:

the MIH entity requesting the UMTS modem to report UMTS signal quality measurement via a Link_Get_Parameter.request API;

the UMTS modem reporting the UMTS signal quality measurement to the MIH entity via a Link_Get_Parameter.confirm API;

the MIH entity sending the UMTS signal quality measurement to an MIH server;

the MIH entity receiving an MIH switch request from the MIH server; and

the MIH entity initiating a handover procedure to the UMTS network.

11. The method of claim 10 wherein the MIH entity uses an AT+CSQ command to request the UMTS signal quality measurement.

12. The method of claim 10 further comprising:

the MIH entity requesting the UMTS modem to create a new packet data protocol (PDP) context;

the MIH entity requesting the UMTS modem to attach to the UMTS network;

the MIH entity requesting the UMTS modem a registration status;

the MIH entity requesting the UMTS modem to activate a PDP context;

the MIH entity requesting the UMTS modem a current setting for defined PDP context;

the MIH entity requesting the UMTS modem to enter a data state;

the MIH entity requesting a mobile Internet protocol (IP) client to perform a discovery of a foreign agent (FA) and mobile IP binding update; and

the MIH entity sending an MIH switch response to the MIH server.

13. The method of claim 12 wherein the MIH entity uses an AT+CGDCONT command to request the new PDP context creation.

14. The method of claim 12 wherein the MIH entity uses an AT+CGATT command to request the attachment.

15. The method of claim 12 wherein the MIH entity uses an AT+CGREG? to request the registration status, and uses an AT+CGACT command to request the PDP context activation.

16. The method of claim 12 wherein the MIH entity uses an AT+CGDCONT? to request the current setting for the defined PDP context, and uses an AT+CGDATA to request the UMTS modem to enter the data state.

17. The method of claim 12 further comprising:

the MIH entity commanding the IEEE 802.16 modem to tear down the IEEE 802.16 link via a Link_Action.request API.

18. The method of claim 12 further comprising:

the MIH entity requesting an IEEE 802.16 quality of service (QoS) parameter from the IEEE 802.16 modem via a Link_Get_Parameter.request API;

the IEEE 802.16 modem sending the requested IEEE 802.16 QoS parameter to the MIH entity via a Link_Get_Parameter.confirm API; and

the MIH entity mapping the IEEE 802.16 QoS parameter to a UMTS QoS parameter and specifying a UMTS QoS profile to the UMTS modem via a Link_Action.request API, wherein the specified UMTS QoS profile is requested to the UMTS network during PDP context activation.

19. The method of claim 18 wherein the MIH entity uses an AT+CGEQREQ command to specify the UMTS QoS profile.

20. The method of claim 12 wherein the MIH entity requests a subscribed QoS profile during PDP context activation.

21. The method of claim 1 further comprising:

if it is indicated that the IEEE 802.16 link has not been successfully established, the MIH entity requesting the UMTS modem to attach to the UMTS network;

the MIH entity requesting the UMTS modem a network registration status;

the MIH entity requesting the UMTS modem to activate a packet data protocol (PDP) context;

the MIH entity requesting the UMTS modem a current setting for defined PDP context;

the MIH entity requesting the UMTS modem to enter a data state; and

the MIH entity requesting a mobile Internet protocol (IP) client to perform mobile IP binding update.

22. The method of claim 1 wherein the first API is a Link_Action.request API, the second API is a Link_Action.confirm API, and the third API is a Link_Going_Down.indication API.

23. A method implemented in a wireless transmit/receive unit (WTRU) for performing handover between an IEEE 802.16 network and a universal mobile telecommunication system (UMTS) network using IEEE 802.21 media independent handover (MIH) functions, the method comprising:

an MIH entity sending a request to a UMTS modem to determine if there is any traffic for the wireless transmit/receive unit (WTRU) on the UMTS network;

if there is no traffic on the UMTS network, the MIH entity requesting an IEEE 802.16 modem to scan the IEEE 802.16 network;

the IEEE 802.16 modem sending a scanning result to the MIH entity;

if the scanning result indicates a detection of an IEEE 802.16 cell, the MIH entity requesting the UMTS modem to perform a packet data protocol (PDP) deactivation and detach procedure; and

the MIH entity requesting the IEEE 802.16 modem to establish an IEEE 802.16 link via an application programming interface (API).

24. The method of claim 23 wherein the MIH entity uses an AT+CGACT command to deactivate the PDP context and uses AT+CGATT command to request the detachment.

25. The method of claim 23 wherein the API is a Link_Action.request API.

26. A wireless transmit/receive unit (WTRU) for supporting media independent handover (MIH) between an IEEE 802.16 network and a universal mobile telecommunication system (UMTS) network, the WTRU comprising:

an IEEE 802.16 modem for establishing a wireless link with the IEEE 802.16 network;

a UMTS modem for establishing a wireless link with the UMTS network;

an upper layer; and

an MIH entity for performing MIH functions, wherein the IEEE 802.16 modem, the UMTS modem, the upper layer and the MIH entity communicate via an application programming interface (API).

27. The WTRU of claim 26 wherein the MIH entity requests the IEEE 802.16 modem to set a threshold for an IEEE 802.16 link parameter which when crossed triggers generation of a measurement report via a Link_Configure_Thresholds.request API and the IEEE 802.16 modem sends a result of such configuration via a Link_Configure_Thresholds.confirm API.

28. The WTRU of claim 26 wherein the IEEE 802.16 modem indicates that a layer 2 connection is expected to go down in a certain time interval via a Link_Going_Down API, and indicates that a link parameter has crossed a threshold via a Link_Patameter_Report.indication API.

29. The WTRU of claim 26 wherein the MIH entity orders the IEEE 802.16 modem to a link layer connection change via a Link_Action.request API, and the IEEE 802.16 modem indicates a status of the link layer connection change via a Link_Action.confirm API.

30. The WTRU of claim 26 wherein the MIH entity requests a quality of service (QoS) parameter for a target application from the IEEE 802.16 modem via a Link_Get_Parameter.request API, and the IEEE 802.16 modem responds with the requested QoS parameter via a Link_Get_Parameters.confirm API.

31. The WTRU of claim 26 wherein the MIH entity requests the UMTS modem to report a UMTS signal quality measurement via a Link_Get_Parameters.request API, and the UMTS modem reports the requested UMTS signal strength measurements via a Link_Get_Parameters.confirm API.

32. The WTRU of claim 31 wherein the MIH entity uses an AT+CSQ command to request the UMTS signal quality measurement.

33. The WTRU of claim 26 wherein the MIH entity, using an AT+CFUN command, activates the UMTS modem to go into one of an idle mode and a connected mode via a Link_Action.request API, and the UMTS modem indicates a status of activation via a Link_Action.confirm API.

34. The WTRU of claim 26 wherein the MIH entity requests the UMTS modem to create a new packet data protocol (PDP) context, attach to the UMTS network, request a registration status, request a PDP context activation, request a current setting for the defined PDP context, and request the UMTS modem to enter a data state via a Link_Action.request API.

35. The WTRU of claim 34 wherein the MIH entity uses an AT+CGDCONT command to request the new PDP context creation, uses an AT+CGATT command to request the attachment, uses an AT+CGREG? to request the registration status, uses an AT+CGACT command to request the PDP context activation, uses an AT+CGDCONT? to request the current setting for the defined PDP context, and uses an AT+CGDATA to request the UMTS modem to enter the data state.

36. The WTRU of claim 26 wherein the upper layer includes a mobile Internet protocol (IP) layer and the API includes an MIH entity-to-mobile IP layer API to request discovery of a mobile IP foreign agent (FA), and a mobile IP layer-to-MIH entity API to confirm discovery of a mobile IP FA.

37. The WTRU of claim 26 wherein the API includes an MIH entity-to-mobile Internet protocol (IP) layer API to perform mobile IP binding update to register new network attachment with a home agent (HA) via a foreign agent (FA), and a mobile IP layer-to-MIH entity API to confirm binding update completion.

38. The WTRU of claim 26 wherein the upper layer includes a mobile Internet protocol (IP) layer and the API includes an MIH entity-to-mobile IP layer API to request information about the number of IP addresses in use and home addresses corresponding to the active IPs, and a mobile IP layer-to-MIH entity API to provide the number of the IP addresses and the corresponding home addresses.

39. The WTRU of claim 26 wherein the upper layer includes a dynamic host configuration protocol (DHCP) layer and the API includes an MIH entity-to-DHCP layer API to discover an Internet protocol (IP) address of a proxy call state control function (P-CSCF), and a DHCP layer-to-MIH entity API to return the result of an attempt to discover the IP address of the P-CSCF.

40. The WTRU of claim 26 wherein the upper layer includes an Internet protocol (IP) multimedia subsystem (IMS) layer and the API includes an MIH entity-to-IMS layer API to register with an IMS, and an API to return results of an attempt to register with the IMS.

41. The WTRU of claim 26 wherein the upper layer includes a transport protocol layer/Internet protocol (IP) layer, and the API includes an MIH entity-to-transport/IP layer API and a transport/IP layer-to-MIH entity API to communicate each other.

42. The WTRU of claim 26 wherein the upper layer includes a dynamic host configuration protocol (DHCP) layer and the API includes an MIH entity-to-DHCP layer API to discover an Internet protocol (IP) address of a network node, and a DHCP layer-to-MIH entity API to return the result of an attempt to discover the network node.

43. The WTRU of claim 26 wherein the upper layer includes an operation and maintenance (O&

M) layer and the API includes an O&

M layer-to-MIH entity API to activate the MIH entity, and an MIH entity-to-O&

M layer API to return the result of an attempt to activate the MIH entity.

44. The WTRU of claim 26 wherein the upper layer includes an operation and maintenance (O&

M) layer and the API includes an O&

M layer-to-MIH entity API to deactivate the MIH entity, and an MIH entity-to-O&

M layer API to return the result of an attempt to deactivate the MIH entity.

45. The WTRU of claim 26 wherein the upper layer includes an operation and maintenance (O&

M) layer and the API includes an O&

M layer-to-MIH entity API to retrieve MIH entity parameters, and an MIH entity-to-O&

M layer API to return the requested MIH entity parameters.

46. The WTRU of claim 26 wherein the upper layer includes an operation and maintenance (O&

M) layer and the API includes an MIH entity-to-O&

M layer API to inform the O&

M layer of handover completion between the IEEE 802.16 network and the UMTS network.

47. The WTRU of claim 26 wherein the upper layer includes an operation and maintenance (O&

M) layer and the API includes an O&

M layer-to-MIH entity API to check a mode of the UMTS modem, and an MIH entity-to-O&

M layer API to return the mode of the UMTS modem.

48. The WTRU of claim 26 wherein the MIH entity is configured to request an IEEE 802.16 quality of service (QoS) parameter from the IEEE 802.16 modem via a Link_Get_Parameter.request API, and map the IEEE 802.16 QoS parameter to a UMTS QoS parameter and specify a UMTS QoS profile to the UMTS modem via a Link_Action.request API, wherein the specified UMTS QoS profile is requested to the UMTS network during PDP context activation.

49. The WTRU of claim 48 wherein the MIH entity uses an AT+CGEQREQ command to specify the UMTS QoS profile.

50. The WTRU of claim 26 wherein the MIH entity is configured to request a subscribed QoS profile during PDP context activation.