METHOD AND APPARATUS FOR SUPPORTING LOCAL IP ACCESS AND SELECTED IP TRAFFIC OFFLOAD

• US 20130003697A1
• Filed: 06/28/2012
• Published: 01/03/2013
• Est. Priority Date: 07/01/2011
• Status: Active Grant

• Current Assignee: InterDigital Patent Holdings, Inc. (InterDigital, Inc.)
• Original Assignee: InterDigital Patent Holdings, Inc. (InterDigital, Inc.)
• Inventors: Adjakple, Pascal M., Ahmad, Saad, Watfa, Mahmoud, Olvera-Hernandez, Ulises
• Granted Patent: US 9,924,413 B2
• Time in Patent Office: Days
• US Class Current: 370/331
• CPC Class Codes: H04L 45/22 Alternate routing
• CPC Class Codes: H04L 45/24 Multipath
• CPC Class Codes: H04L 45/74 Address processing for routing
• CPC Class Codes: H04W 12/068 using credential vaults, e.g. password manager applications or one time password [OTP] applications
• CPC Class Codes: H04W 12/08 Access security
• CPC Class Codes: H04W 36/0011 for data sessions of end-to-end connection
• CPC Class Codes: H04W 36/125 involving different types of service backbones
• CPC Class Codes: H04W 40/34 Modification of an existing route
• CPC Class Codes: H04W 48/16 Discovering, processing access restriction or access information
• CPC Class Codes: H04W 76/12 Setup of transport tunnels
• CPC Class Codes: H04W 8/082 for traffic bypassing of mobility servers, e.g. location registers, home PLMNs or home agents
• CPC Class Codes: H04W 84/045 using private Base Stations, e.g. femto Base Stations, home Node B

Abstract

A method and apparatus for home Node-B (HNB) mobility with a local IP access (LIPA) packet data network (PDN) connection are described. A target home node-B (HNB) may receive a handover request message from a source HNB to handover a wireless transmit/receive unit (WTRU). A path switch request may be transmitted to a local gateway (LGW) to change a downlink data path towards the target HNB in response to the handover request message. The LGW may act as a mobility management and local mobility anchor for the handover; and informing an HNB gateway (GW) about the handover so that the downlink data path for core network (CN) traffic is modified towards the target HNB.

Claims

1. A method, implemented at a target home node-B (HNB), for local IP access (LIPA) packet data network (PDN) connection mobility, the method comprising:

receiving a handover request message from a source HNB to handover a wireless transmit/receive unit (WTRU);

sending a path switch request to a local gateway (LGW) to change a downlink data path towards the target HNB in response to the handover request message, wherein the LGW acts as mobility management and local mobility anchor for the handover; and

informing an HNB gateway (GW) about the handover so that the downlink data path for core network (CN) traffic is modified towards the target HNB.

2. The method of claim 1, further comprising:

sending a path switch request to a mobility management entity (MME)/serving gateway (SGW) about the handover so that the downlink data path for the CN traffic is modified towards the target HNB.

3. The method of claim 1, wherein an HNB acting as a serving radio network subsystem (SRNS) continues to be in charge of radio connection between the WTRU and a radio access network (RAN) after the handover.

4. The method of claim 3, wherein control plane signaling is maintained at the HNB acting as the SRNS.

5. The method of claim 3, wherein the HNB acts as the SRNS on a condition that the WTRU is not on a closed subscriber group subscription list.

6. The method of claim 1, further comprising:

initiating LIPA PDN suspension on a condition that the LIPA PDN connection is unsupported by the target HNB.

7. A method, implemented at a network node, for handling local IP access (LIPA) packet data network (PDN) connection during CELL_FACH mobility, the method comprising:

receiving a cell update message from a wireless transmit/receive unit (WTRU);

determining support of the LIPA PDN connection at a target cell in response to the cell update message; and

deactivating the LIPA PDN connection on a condition that the target cell does not support LIPA PDN connections.

8. The method of claim 7, wherein the cell update message includes an indication of an existing LIPA PDN connection.

9. The method of claim 7, wherein the LIPA PDN support determination is done by at least one of the target cell, a source cell or a core network.

10. The method of claim 7, wherein the WTRU disables CELL_FACH mobility on a condition of an active LIPA PDN connection.

11. A method, implemented at a source home node-B (HNB), for inter-local gateway (LGW) mobility, the method comprising:

determining that a target HNB is not connected to a source LGW;

verifying that the source LGW and a target LGW can be connected; and

establishing a tunnel between the source LGW and the target LGW on a condition that the source LGW and a target LGW can be connected; and

forwarding data to the target LGW on a condition that the tunnel is established.

12. The method of claim 11, further comprising:

forwarding data from the source HNB to a target HNB via X2 or Iurh interface.

13. The method of claim 11, wherein a network node selects the target LGW based on information from the WTRU.

14. A method, implemented at a wireless transmit/receive unit (WTRU), for verifying membership, the method comprising:

receiving a broadcast public land mobile network (PLMN);

determining existence of broadcast PLMN on whitelist; and

modifying the whitelist to include the broadcast PLMN on a condition that a broadcast closed subscriber group (CSG) ID is on the whitelist and that a PLMN associated with a whitelist CSG ID is equivalent to the broadcast PLMN.

15. The method of claim 14, wherein the WTRU transmits modification information to a network.

16. A target home node-B (HNB), comprising:

the target HNB configured to receive a handover request message from a source HNB to handover a wireless transmit/receive unit (WTRU) that has a local IP access (LIPA) packet data network (PDN) connection;

the target HNB configured to send a path switch request to a local gateway (LGW) to change a downlink data path towards the target HNB in response to the handover request message, wherein the LGW acts as mobility management and local mobility anchor for the handover; and

the target HNB configured to inform an HNB gateway (GW) about the handover so that the downlink data path for core network (CN) traffic is modified towards the target HNB.

17. The target HNB of claim 16, further comprising:

the target HNB configured to send a path switch request to a mobility management entity (MME)/serving gateway (SGW) about the handover so that the downlink data path for the CN traffic is modified towards the target HNB.

18. The target HNB of claim 16, wherein an HNB acting as a serving radio network subsystem (SRNS) continues to be in charge of radio connection between the WTRU and a radio access network (RAN) after the handover.

19. The target HNB of claim 18, wherein control plane signaling is maintained at the HNB acting as the SRNS.

20. The target HNB of claim 18, wherein the HNB acts as the SRNS on a condition that the WTRU is not on a closed subscriber group subscription list.