Method, system and evolved NodeB apparatus for implementing inter-evolved NodeB handover

• US 8,804,667 B2
• Filed: 08/11/2010
• Issued: 08/12/2014
• Est. Priority Date: 02/25/2010
• Status: Active Grant

• Current Assignee: ZTE Corporation
• Original Assignee: ZTE Corporation
• Inventors: Wang, Xintai
• Primary Examiner(s): Phan, Tri H
• Application Number:
  US13/579,800
• Publication Number:
  US 20120314689A1
• Time in Patent Office: 1,462 Days
• Field of Search: 370328-332, 370/338, 370/341, 370400-401, 370/431, 370/437, 370/439, 370/464, 4554321-444, 455449-466
• US Class Current: 370/331
• CPC Class Codes: H04W 36/12 Reselecting a serving backbone network switching or routing node
• CPC Class Codes: H04W 76/22 Manipulation of transport tunnels

Abstract

A method, a system and an evolved NodeB (eNB) apparatus for implementing inter-eNB switch are disclosed in the present invention. The method includes: when a user equipment switches from a source-side eNB to a target-side eNB, if the target-side eNB acquires via the Mobility Management Entity (MME) that the Serving Gateway (S-GW) has changed, the target-side eNB adds the new route relation of the S-GW and then updates the General Packet Radio Service (GPRS) Tunnelling Protocol User Plane (GTP-U) entity. The present invention can effectively solve the problem of the uplink data packet loss due to the time difference existing between the update to the Tunnel Endpoint Identifier (TEID) and the routing table by the eNB when inter-eNB switch is performed via X2 and the S-GW has changed, thus enhancing the user experience during the switch.

Claims

1. A method for implementing inter-eNB switch, comprising the following steps of:

when a user equipment switches from a source-side eNB to a target-side eNB, the target-side eNB, after the switch is completed, sending to a Mobility Management Entity (MME) a PATH SWITCH REQUEST message to indicate that the eNB side has changed;

the MME, after completing update of the S-GW, sending to the target-side eNB a PATH SWITCH REQUEST ACKNOWLEDGE message for indicating whether a Serving Gateway(S-GW) has changed or not;

if the target-side eNB acquires via the MME that the S-GW has changed, the target-side eNB adding a new routing relation of the S-GW and then updating a General Packet Radio Service(GPRS) Tunnelling Protocol User Plane (GTP-U) entity; and

the target-side eNB deleting an old routing relation of the S-GW after successfully completing update of the GTP-U entity.

2. The method according to claim 1, wherein, the PATH SWITCH REQUEST message carries evolved radio access bearer (E-RAB) information to be switched for indicating that a Tunnel End Point Identifier (TEID) at the eNB side has changed;

after completion of update of the S-GW, i.e., after completion of switch of all or part of GTP-U tunnels, the MME sends to the target-side eNB the PATH SWITCH REQUEST ACKNOWLEDGE message for indicating whether the S-GW has changed or not according to whether the PATH SWITCH REQUEST ACKNOWLEDGE message carries uplink updated service information;

the step of the target-side eNB acquiring via the MME that the S-GW has changed comprises;

the target-side eNB checking whether the PATH SWITCH REQUEST ACKNOWLEDGE message sent by the MME carries the uplink updated service information containing the E-RAB information that needs to be updated, if yes, the target-side eNB acquiring that the S-GW has changed;

wherein,

the E-RAB information comprises one or more of an evolved radio access bearer identity (E-RABID), a transmission layer address and TEID information.

3. The method according to claim 2, wherein, the step of the target-side eNB adding a new routing relation of the S-GW and then updating a GTP-U entity comprises:

the target-side eNB adding new routing information of the S-GW in a rouging information record according to the TEID and transmission layer address;

updating the GTP-U entity by updating the TEID at the MME side or the S-GW side in a TEID pair of the E-RAB information;

the step of the target-side eNB deleting an old routing relation of the S-GW after successfully completing update of the GTP-U entity is;

if the target-side eNB successfully updates the GTP-U entity, deleting the old routing information of the S-GW from the routing information record.

4. The method according to claim 3, further comprising:

the target-side eNB using updated GTP-U entity and parameters to transmit and receive data.

5. A system for implementing inter-eNB switch, comprising a target-side eNB and a Mobility Management Entity (MME), wherein:

the target-side eNB is configured to, after completing a switch of a user equipment (UE) from a source-side eNB, send to the MME a message for notifying that the eNB side has changed;

when acquiring via the MME that a Serving Gateway(S-GW) has changed, add a new routing relation of the S-GW and then update a General Packet Radio Service (GPRS) Tunnelling Protocol User Plane (GTP-U) entity, and delete an old routing relation of the S-GW after successfully completing update of the GTP-U entity;

the MME is configured to, after completing update of the S-GW, send to the target-side eNB a message to inform the target-side eNB of whether the S-GW has changed or not.

6. The system according to claim 5, wherein,

the target-side eNB is configured to acquire via the MME that the S-GW has changed in the following way:

carrying evolved radio access bearer (E-RAB) information to be switched in the message sent to the MME for indicating that a Tunnel End Point Identifier (TEID) at the eNB side has changed;

if it is checked that the message returned by the MME carries uplink updated service information containing the E-RAB information that needs to be updated, acquiring that the S-GW has changed, wherein the E-RAB information comprises one or more of an evolved radio access bearer identity (E-RABID), a transmission layer address and TEID information;

the MME is configured to inform the target-side eNB of whether the S-GW has changed or not in the following way;

after successfully completing update of the S-GW, i.e., after successfully completing switch of all or part of GTP-U tunnels, sending to the target-side eNB a message for indicating whether the S-GW has changed or not according to whether the message carries the uplink updated service information.

7. The system according to claim 6, wherein, the target-side eNB is configured to add a new routing relation of the S-GW and then update the GTP-U entity in the following way:

adding new routing information of the S-GW in a rouging information record according to the TEID and transmission layer address;

updating the GTP-U entity by updating the TEID at the MME side or the S-GW side in a TEID pair of the E-RAB information; and

the target-side eNB is configured to delete an old routing relation of the S-GW in the following way;

if the GTP-U entity is successfully updated, deleting the old routing information of the S-GW from the routing information record.

8. The system according to claim 7, wherein, the target-side eNB is further configured to use updated GTP-U entity and parameters to transmit and receive data.

9. An evolved NodeB (eNB) apparatus for implementing inter-eNB switch, comprising a control-plane sub-system, a user-plane sub-system and a route sub-system, wherein,

the control-plane sub-system is configured to, after completing a switch of a user equipment (UE) from a source-side eNB, when acquiring via a Mobility Management Entity (MME) that a Serving Gateway(S-GW) has changed, notify the route sub-system to add a new routing relation and then notify the user-plane sub-system to update a General Packet Radio Service(GPRS) Tunnelling Protocol User Plane (GTP-U) entity;

the route sub-system is configured to add new routing information of the S-GW according to a notification of the control-plane sub-system;

the user-plane sub-system is configured to update the GTP-U entity according to a notification of the control-plane sub-system, and

wherein,

the user-plane sub-system is further configured to return an update result to the control-plane sub-system after completing update of the GTP-U entity;

the control-plane sub-system is further configured to notify the route sub-system to delete old routing information of the S-GW if judging that the update result returned by the user-plane sub-system is “

successful”

; and

notify the route sub-system to delete added new routing information of the S-GW if judging that the update result is “

unsuccessful”

;

the route sub-system is further configured to delete old routing information of the S-GW or add new routing information of the S-GW in a routing information record.

10. The apparatus according to claim 9, wherein,

the control-plane sub-system is configured to acquire via the MME that the S-GW has changed in the following way:

after completion of the switch of the UE from the source-side eNB, sending to the MME a message carrying evolved radio access bearer E-RAB information to be switched for indicating that a Tunnel End Point Identifier (TEID) at the eNB side has changed;

if it is checked that the message returned by the MME carries uplink updated service information containing the E-RAB information that needs to be updated, acquiring that the S-GW has changed, and the E-RAB information comprising one or more of an evolved radio access bearer identity (E-RABID), a transmission layer address and TEID information;

the route sub-system is configured to add new routing information of the S-GW in a rouging information record according to the TEID and transmission layer address carried in the message of the control-plane sub-system;

the user-plane sub-system is configured to update the GTP-U entity in the following way;

updating the TEID at the MME side or the S-GW side in a TEID pair of the E-RAB information and a target address according to the TEID and transmission layer address carried in the message of the control-plane sub-system.

11. The system according to claim 10, wherein, the user-plane sub-system is further configured to use updated GTP-U entity and parameters to transmit and receive data.