CN109874180B - LTE and WLAN interconnection method and system - Google Patents

Abstract

The invention provides a method and a system for interconnecting an LTE (Long term evolution) and a WLAN (Wireless local area network), wherein the method comprises the following steps: the relay node RN and the wireless local area network termination node WT establish an Xw interface; RN sends WT addition request message to WT through Xw interface; the WT determines a second bearer list according to the first bearer list and the WLAN mobile set in the WT addition request message and sends a WT addition request confirmation message to the RN through an Xw interface; when the RN receives a WT addition request confirmation message through an Xw interface, the RN sends an RRC connection reconfiguration message to the UE; and the UE performs service steering according to the RRC connection reconfiguration message. The method and the system for interconnecting the LTE and the WLAN realize that the RN shunts the service data of the UE through the WLAN, and improve the service quality of the service diverted to the WLAN.

Description

LTE and WLAN interconnection method and system

Technical Field

The invention relates to the technical field of communication, in particular to a method and a system for interconnecting an LTE (Long term evolution) network and a WLAN (Wireless local area network).

Background

Currently, the 3GPP protocol supports RCLWI (RCLWI: RAN controlled LTE-WLAN Interworking, interconnection of LTE controlled by RAN and WLAN; RAN: Radio Access Network, Radio Access Network; LTE: Long Term evolution; WLAN: Wireless Local Area Network). In RCLWI, for a UE (UE: User Equipment) in RRC _ CONNECTED (RRC _ CONNECTED: RRC CONNECTED state; RRC: Radio Resource Control), E-UTRAN supports bidirectional traffic steering (traffic steering) between E-UTRAN and WLAN under the Control of E-UTRAN: for a UE at RRC _ CONNECTED, the E-UTRAN controls the selection of access networks and traffic steering between LTE and WLAN.

Specifically, when the eNB decides to divert a part of the traffic of the UE from LTE to WLAN, an RRC connection reconfiguration message is sent to the UE, where the message carries a traffic steering command. The eNB would carry in this command: an indication that traffic is diverted to WLAN and a WLAN Mobility Set (WLAN Mobility Set). And after receiving the command, the UE stores the WLAN mobile set and feeds back an RRC connection reconfiguration completion message to the eNB. Then, the UE performs a WLAN status listening procedure. In which the UE attempts to connect with an AP in the WLAN mobility set. The UE may select an AP from the WLAN Mobility Set for connection, and if the UE can connect to the AP, the UE reports a WLAN connection success to the eNB through a WLANConnectionStatusReport message. If the connection fails, the UE will attempt to connect to another AP in the WLAN Mobility Set. If the UE cannot be connected with any AP in the WLAN Mobility Set, the UE reports WLAN connection failure to the eNB through a WLANConnectionStatusReport message. After the UE successfully connects to an AP, the UE accesses the EPC through the AP and then transmits selected traffic directed to the WLAN through the AP and the EPC.

And when the eNB decides to switch the service of the UE from the WLAN to the LTE, sending an RRC connection reconfiguration message to the UE, wherein the message carries traffic steering command. The command carries: indication of traffic steering to LTE. After receiving the message, according to the indication of traffic steering command, the UE deletes the stored WLAN mobility set, stops the WLAN status monitoring process, and transmits the traffic transmitted through the WLAN before through LTE. If the traffic reconfiguration command is carried in the RRC connection reconfiguration message sent by the eNB to the UE: releasing the RCLWI configuration instruction, deleting the WLAN mobile set after the UE receives the message, stopping WLAN state monitoring, and informing the upper layer that the RCLWI configuration is released.

In RCLWI, to configure a UE with a WLAN mobility set to support movement of the UE between different APs, the eNB needs to configure the UE with WLAN measurements, indicating which APs the UE needs to measure. And the UE carries out measurement according to the configuration and reports the measurement result to the eNB. And the eNB configures a unique WLAN mobile set for the UE according to the measurement result of each WLAN AP reported by the UE. The WLAN APs in the set are associated with or hung below the same WT (WT: WLAN Termination node). The UE performs WLAN measurements simultaneously as the UE moves between different APs in the set. When the measurement event is triggered or the periodic measurement report is triggered, the UE reports the new WLAN measurement result to the eNB. The eNB may update the WLAN mobility set according to the measurement result of each WLAN reported by the UE: some APs in the set are deleted or some APs are added to the set. When the eNB associates a new WT with several APs selected by the eNB based on the UE's measurements, the eNB may configure the UE with a new WLAN Mobility Set. When the UE receives the newly configured WLAN Mobility Set, it saves the Set and tries to connect to the APs in the Set.

In RCLWI, the eNB instructs the UE to transmit service data through WLAN or LTE through traffic steering command, which not only can effectively relieve the congestion and busyness of the UL/DL of the Uu interface, but also can fully utilize WLAN resources to ensure the service experience of the UE. The RCLWI enables the eNB to allocate the UL/DL resources of the Uu interface to the UE with good UL/DL channel quality so as to transmit UL/DL service data of the UE, improve the uplink/downlink peak rate and uplink/downlink throughput of the UE, and improve the uplink/downlink peak rate and uplink/downlink throughput of the cell. Meanwhile, for the UE which has poor UL/DL channel quality of a Uu interface, is in a WLAN coverage area and supports RCLWI, the service of the UE is transmitted through the WLAN, and the service experience of the UE can be improved. When the eNB finds that the WLAN coverage is poor through the WLAN measurement report of the UE, the eNB can send traffic steering command to the UE, the service shunted to the WLAN is transmitted again through the LTE, and the service experience of the UE is improved.

However, when the eNB is used as a DeNB (Doner eNB: donor eNB) to hang down the RN (Relay Node: Relay Node), the 3GPP protocol does not support the RN to connect with the WLAN, so that the RN cannot shunt the uplink/downlink traffic data of the UE accessing the RN through the WLAN.

An interface between the RN and the UE is Uu, an interface between the RN and the DeNB is Un, and the RN cannot simultaneously transmit or receive data between the Uu and the Un, so that the Uu and the Un time division multiplex uplink/downlink subframes: both interfaces use uplink subframes to transmit data and both use downlink subframes to receive data. And the DeNB configures an RN subframe allocation mode for the RN, and indicates which downlink subframes are used for transmitting by the DeNB-to-RN and which uplink subframes are used for transmitting by the RN-to-DeNB. According to the different types of data transmitted on Un, two logical interfaces are defined on Un: s1 and X2. The DeNB forwards S1 information between the EPC and the RN through logical interface S1, and forwards X2 information between another eNB and the RN through logical interface X2.

Since Uu and Un use all uplink subframes and all downlink subframes in a time division multiplexing manner to realize transmission of uplink data and reception of downlink data of two interfaces, and Un is a wireless interface rather than a wired interface, uplink and downlink rates of RN are limited in Uu and Un compared with Uu and S1/X2 of eNB. Therefore, if the RN supports the RCLWI, the RN can allocate the Uu interface UL/DL resources to the UE with good UL/DL channel quality, and let the UE with poor Uu interface UL/DL channel quality in the WLAN coverage area transmit the traffic through the WLAN. Therefore, the UL/DL peak rate and the UL/DL throughput of the RN cell can be greatly improved; for the traffic shunted to the WLAN, the service experience of the UE can also be improved through the good coverage of the WLAN. Meanwhile, the UE accesses the EPC through the WLAN, the service distributed to the WLAN is directly transmitted to the EPC through the AP, the transfer of the service distributed to the WLAN by the Un upper logic interface S1 is not needed at all, and the service passing through the Un can be effectively distributed.

Disclosure of Invention

The invention provides a method and a system for interconnecting an LTE (Long term evolution) and a WLAN (Wireless local area network), which are used for realizing that RN (radio network) shunts service data of UE (user equipment) through the WLAN and improving the service quality of a service diverted to the WLAN.

The embodiment of the invention provides a method for interconnecting an LTE (Long term evolution) and a WLAN (Wireless local area network), which comprises the following steps:

the relay node RN and the wireless local area network termination node WT establish an Xw interface;

the RN sends a WT addition request message to the WT through the Xw interface; the WT add request message includes a first bearer list and a WLAN mobility set; the first bearer list is an EPS bearer list which is determined by the RN in all EPS bearers of the UE and needs to be steered to the WLAN; the WLAN mobile set is a set of Access Points (APs) with better signal quality around the UE, and all APs in the AP set correspond to the same WT;

the WT determines a second bearer list according to the first bearer list and the WLAN mobile set and sends a WT addition request acknowledgement message to the RN through the Xw interface; wherein, the WT addition request acknowledge message includes a MAC address of the WT, a second bearer list and a third bearer list, and the second bearer list is an EPS bearer list in which the WT successfully allocated WLAN radio resources in the first bearer list; the third bearer list is an EPS bearer list in the first bearer list for which the WT failed to allocate WLAN radio resources;

when the RN receives a WT addition request confirmation message through the Xw interface, the RN sends a Radio Resource Control (RRC) connection reconfiguration message to the UE; the RRC connection reconfiguration message is used for indicating the UE to carry out configuration according to the RRC connection reconfiguration message; the RRC connection reconfiguration message comprises a service steering command; the traffic steering command includes an indication to steer the WLAN, a WLAN mobility set, a WT's MAC address, and a fourth bearer list;

and the UE carries out service steering according to the RRC connection reconfiguration message.

In an embodiment of the present invention, the performing, by the UE, service steering according to the RRC connection reconfiguration message includes:

the UE saves the service steering command in the RRC connection reconfiguration message and sends an RRC connection reconfiguration completion message to the RN; the RRC connection reconfiguration complete message is used for indicating that the UE configuration is complete;

the UE attempting to establish a connection with an AP in the WLAN mobility set in the traffic steering command; if the traffic steering command stored by the UE carries the MAC address of the WT, the UE is associated with the corresponding WT according to the MAC address of the WT after establishing connection with an AP;

the UE establishes connection with an EPC through the AP establishing connection;

the UE applies for resources from an EPC for services corresponding to each EPS bearer in the fourth bearer list through the AP, and establishes corresponding bearers transmitted through the AP;

and the UE transmits the service to be diverted through the bearer transmitted by the AP.

In an embodiment of the present invention, the UE attempts to establish a connection with an AP in a WLAN mobility set; if the traffic steering command stored by the UE carries a WT MAC address, after the UE establishes a connection with an AP and associates with a corresponding WT according to the WT MAC address, the method further includes:

the WT sends a WT association confirmation message to the RN through the Xw interface;

the RN determines a UE associated with a corresponding WT according to the WT association confirmation message.

In an embodiment of the present invention, the UE attempts to establish a connection with an AP in a WLAN mobility set; if the traffic steering command stored by the UE carries a WT MAC address, associating with a corresponding WT according to the WT MAC address after the UE establishes a connection with an AP, further comprising:

the UE sends a WLAN connection state reporting message to the RN; wherein, the connection status report message is used to indicate that the UE is connected to the WLAN;

and the RN determines that the UE is connected to the WLAN according to the connection state reporting message.

In an embodiment of the present invention, the establishing, by the relay node RN and the wireless local area network termination node WT, an Xw interface includes:

the RN sends an Xw interface establishment request message to the WT; the Xw interface establishment request message comprises an RN identifier;

and the WT establishes the Xw interface with the RN according to the RN identification.

And the WT sends an Xw interface establishment response message to the RN through the Xw interface, wherein the Xw interface establishment response message is used for indicating that the establishment of the Xw interface is successful, and the Xw interface establishment response message comprises a WT identifier and a WLAN AP list hung under the WT.

In an embodiment of the present invention, after the WT determines the second bearer list according to the first bearer list and the WLAN mobility set, the method further includes:

when the second bearer list does not include any EPS bearers, the WT sends a WT addition request reject message to the RN.

The embodiment of the invention also provides a system for interconnecting the LTE and the WLAN, which comprises the following steps: a relay node RN, a wireless local area network termination node WT and user equipment UE;

wherein the RN is used for establishing an Xw interface with the WT;

the RN is further configured to send a WT add request message to the WT over the Xw interface; the WT add request message includes a first bearer list and a WLAN mobility set; the first bearer list is an EPS bearer list which is determined by the RN in all EPS bearers of the UE and needs to be steered to the WLAN; the WLAN mobile set is a set of Access Points (APs) with better signal quality around the UE, and all APs in the AP set correspond to the same WT;

the WT is configured to determine a second bearer list according to the first bearer list and the WLAN mobility set, and send a WT addition request acknowledgement message to the RN through the Xw interface; wherein, the WT addition request acknowledge message includes a MAC address of the WT, a second bearer list and a third bearer list, and the second bearer list is an EPS bearer list in which the WT successfully allocated WLAN radio resources in the first bearer list; the third bearer list is an EPS bearer list in the first bearer list for which the WT failed to allocate WLAN radio resources;

when the RN receives a WT addition request confirmation message through the Xw interface, the RN is also used for sending an RRC connection reconfiguration message to the UE; the RRC connection reconfiguration message is used for indicating the UE to carry out configuration according to the RRC connection reconfiguration message; the RRC connection reconfiguration message comprises a service steering command; the traffic steering command includes an indication to steer the WLAN, a WLAN mobility set, a WT's MAC address, and a fourth bearer list;

and the UE is used for carrying out service steering according to the RRC connection reconfiguration message.

In an embodiment of the present invention, the UE is specifically configured to store a service steering command in the RRC connection reconfiguration message, and send an RRC connection reconfiguration complete message to the RN; the RRC connection reconfiguration complete message is used for indicating that the UE configuration is complete; the UE attempting to establish a connection with an AP in the WLAN mobility set in the traffic steering command; if the traffic steering command stored by the UE carries the MAC address of the WT, the UE is associated with the corresponding WT according to the MAC address of the WT after establishing connection with an AP; establishing connection with the EPC through the AP for establishing connection; applying for resources to the EPC for the service corresponding to each EPS bearer in the fourth bearer list through the AP, and establishing a corresponding bearer transmitted through the AP; and is used for transmitting the traffic to be diverted through the bearer transmitted by the AP.

In an embodiment of the present invention, the WT is further configured to send a WT association confirm message to the RN through the Xw interface;

the RN is further configured to determine a UE associated with the corresponding WT from the WT association confirmation message.

In an embodiment of the present invention, the UE is further configured to send a WLAN connection status report message to the RN; wherein, the connection status report message is used to indicate that the UE is connected to the WLAN;

and the RN is also used for determining that the UE is connected to the WLAN according to the connection state reporting message.

In an embodiment of the present invention, the RN is specifically configured to send an Xw interface setup request message to the WT; the Xw interface establishment request message comprises an RN identifier;

the WT is further configured to establish the Xw interface with the RN according to the RN identifier;

the WT is further configured to send an Xw interface setup response message to the RN through the Xw interface, where the Xw interface setup response message is used to indicate that the Xw interface setup is successful, and the Xw interface setup response message includes a WT identifier and a WLAN AP list on which the WT hangs down.

In an embodiment of the present invention, the WT is further configured to send a WT addition request reject message to the RN when the second bearer list does not include any EPS bearer.

In the method and the system for interconnecting the LTE and the WLAN, provided by the embodiment of the invention, the RN and the WT establish an Xw interface; sending a WT addition request message to the WT through an Xw interface, so that the WT can determine a second bearer list according to the first bearer list and the WLAN mobile set in the WT addition request message, and sending a WT addition request confirmation message to the RN through the Xw interface; when the RN receives a WT addition request confirmation message through an Xw interface, the RN sends an RRC connection reconfiguration message to the UE; the UE carries out service steering according to the RRC connection reconfiguration message, so that the RN shunts the service data of the UE through the WLAN, and the service quality of the service steered to the WLAN is improved.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present disclosure and together with the description, serve to explain the principles of the disclosure.

FIG. 1 is a diagram of a system architecture according to an embodiment of the present invention;

fig. 2 is a schematic diagram of a method for interconnecting LTE and WLAN according to an embodiment of the present invention;

fig. 3 is a control plane protocol architecture diagram of an Xw interface according to an embodiment of the present invention;

fig. 4 is a schematic diagram of another LTE-WLAN interworking method according to an embodiment of the present invention;

fig. 5 is a schematic diagram of an LTE-WLAN interworking system according to an embodiment of the present invention.

With the foregoing drawings in mind, certain embodiments of the disclosure have been shown and described in more detail below. These drawings and written description are not intended to limit the scope of the disclosed concepts in any way, but rather to illustrate the concepts of the disclosure to those skilled in the art by reference to specific embodiments.

Detailed Description

Reference will now be made in detail to the exemplary embodiments, examples of which are illustrated in the accompanying drawings. When the following description refers to the accompanying drawings, like numbers in different drawings represent the same or similar elements unless otherwise indicated. The implementations described in the exemplary embodiments below are not intended to represent all implementations consistent with the present disclosure. Rather, they are merely examples of apparatus and methods consistent with certain aspects of the present disclosure, as detailed in the appended claims.

The terms "first," "second," "third," "fourth," and the like in the description and in the claims, as well as in the drawings, if any, are used for distinguishing between similar elements and not necessarily for describing a particular sequential or chronological order. It is to be understood that the data so used is interchangeable under appropriate circumstances such that the embodiments of the invention described herein are, for example, capable of operation in sequences other than those illustrated or otherwise described herein. Furthermore, the terms "comprises," "comprising," and "having," and any variations thereof, are intended to cover a non-exclusive inclusion, such that a process, method, system, article, or apparatus that comprises a list of steps or elements is not necessarily limited to those steps or elements expressly listed, but may include other steps or elements not expressly listed or inherent to such process, method, article, or apparatus.

Fig. 1 is a system architecture diagram according to an embodiment of the present invention, please refer to fig. 1, in which the communication system includes: UE (not shown), RN, eNB, DeNB, WT, and MME (MME: Mobility Management Entity)/S-GW (S-GW: serving Gateway). In the system architecture shown in fig. 1; the eNB can interact with MME/S-GW through an S1 interface, the eNB can also interact with WT through an Xw interface, and the Xw interface is established between RN and WT, so that RN interacts with WT through the Xw interface, one eNB can correspond to a plurality of WT, and one RN can also correspond to a plurality of WT.

The Xw interface between RN and WT only transmits control plane information and does not transmit user plane information. Therefore, the Xw interface can also be represented by an Xw-C (Xw-Control plane: Xw Control plane interface) interface.

In the conventional RCLWI, the 3GPP protocol does not support the RN to connect with the WLAN, so that the RN cannot offload uplink/downlink service data of the UE accessing the RN through the WLAN. In order to realize that RN shunts the service data of UE through WLAN and improve the service quality of the service diverted to WLAN, the invention provides a method for interconnecting LTE and WLAN, which comprises the following steps: the RN and the WT establish an Xw interface; for UE which supports RCLWI function, RN configures WLAN measurement for UE, and determines WLAN mobile set of UE according to WLAN measurement report of UE, then RN dynamically updates WLAN mobile set of UE whenever receiving WLAN measurement report of UE; when the RN determines that services corresponding to certain EPS bearers of the UE are transmitted through the WLAN, the RN sends a WT addition request message to the WT through an Xw interface, wherein the message carries a first bearer list and a WLAN mobile set of the UE, the first bearer list is an EPS bearer list which is determined by the RN and needs to be steered to the WLAN, and the RN applies for WLAN resources from the corresponding WT in advance for the services corresponding to the EPS bearers which are determined by the RN and need to be steered to the WLAN; the WT determines a second bearer list according to the first bearer list and the WLAN mobile set in the WT addition request message, and sends a WT addition request confirmation message to the RN through an Xw interface, wherein the message carries the second bearer list, and the second bearer list is a list of bearers which can be provided by the WT in the first bearer list and transmitted by WLAN resources; when the RN receives a WT addition request confirmation message through an Xw interface, the RN sends an RRC connection reconfiguration message to the UE, wherein the message carries a second bearer list; the UE performs service steering according to the RRC connection reconfiguration message, thereby realizing that the RN shunts the service data of the UE through the WLAN and improving the service quality of the service steered to the WLAN.

The technical means of the present invention will be described in detail below with reference to specific examples. It should be noted that the following embodiments may be combined with each other, and the description of the same or similar contents in different embodiments is not repeated.

Fig. 2 is a schematic diagram of an LTE-WLAN interworking method according to an embodiment of the present invention, please refer to fig. 2, where the LTE-WLAN interworking method may include:

and S200, establishing an Xw interface between the RN and the WT.

For the RN supporting the RCLWI, in the co-location scenario, the RN is connected with the WLAN through an internal interface. In the non-co-location scenario, the RN and the WLAN are interconnected through an Xw interface. One RN may connect multiple WTs. The WT is on the WLAN side and terminates Xw. Each WT hangs down multiple WLAN APs. Since the interface between RN and WT is functionally identical to the interface between eNB and WT supporting RCLWI, the Xw interface is used here to indicate the interface between RN and WT, although the interface may differ in specific application layer procedures.

The RN supporting the RCLWI and the DeNB supporting the RN with the RCLWI capability hanging down are respectively added with some functions in the RN starting process. Specifically, in the RN starting process:

(1) and the RN newly adds the capability of reporting the RCLWI support to the DeNB.

(2) The RN and the DeNB support a newly-added RN subframe configuration mode, the newly-added RN subframe configuration mode at least comprises a newly-added RN subframe configuration mode, and any one newly-added RN subframe configuration mode can configure more uplink or downlink subframes to the Un so as to improve the uplink or downlink capacity of the Un.

(3) The DeNB selects one configuration pattern from all RN subframe configuration patterns (including a newly-added RN subframe configuration pattern) to be carried to the RN through the RN reconfiguration message.

(4) And the RN sets uplink and downlink transmitted subframes of the Un according to the RN subframe configuration mode in the RN reconfiguration message, and supports the allocation of more uplink or downlink subframes to the Un under the condition that the configuration mode is a newly added RN subframe configuration mode.

(5) The OAM system of RN is added to RN supporting RCLWI to configure candidate WT list, the coverage of WT in the list should overlap with that of RN, and the coverage of WT is the sum of the coverage of all WLAN APs hung by WT.

(6) The RN maintains a list of candidate WTs for configuration.

It should be noted that, the function of configuring, by the OAM system of the RN in (5), the WT list to the RN supporting the RCLWI may also be migrated to the DeNB: the RN reconfiguration message sent by the DeNB to the RN supporting the RCLWI carries not only the RN subframe configuration pattern but also a list of candidate WTs within the RN coverage.

After the RN start-up procedure, the RN in turn establishes an Xw interface with the WTs in the candidate WT list. For any WT in the candidate WT list, the RN first establishes a protocol architecture of an Xw interface control plane for the WT on its own side, where the protocol architecture of the interface control plane is as shown in fig. 3, fig. 3 is a control plane protocol architecture diagram of an Xw interface provided in the embodiment of the present invention, and Xw-C in the diagram indicates an Xw interface control plane. The RN initiates a first Xw-C AP process on an Xw-C AP layer: an Xw interface Setup (Xw Setup) procedure establishes an Xw interface connection with the candidate WT.

Specifically, the RN sends an Xw SETUP REQUEST message (Xw SETUP REQUEST) to the candidate WT, where the Xw SETUP REQUEST message carries the RN ID. The WT saves the RN ID in the Xw SETUP request message and replies to an Xw SETUP RESPONSE message (Xw SETUP RESPONSE), which at least carries the WT ID and the WLAN AP list on which the WT is hanging down. When the WT has no available WLAN wireless resources, the WT sends an Xw SETUP FAILURE message (Xw SETUP FAILURE) to the RN, the RN saves the configuration information in the Xw SETUP response message after receiving the Xw SETUP response message sent by the WT, and the SETUP of the Xw interface between the RN and the WT is completed. If the RN receives the Xw establishment failure message, it indicates that the Xw establishment between the RN and the WT failed, and at this time, it may try to establish an Xw interface with the WT after a period of time.

After the RN and the WT are connected through Xw, the RN and the WT may initiate the following Xw-cap procedure through an Xw-cap (Xw-C application protocol) layer of Xw-C, specifically:

(1) the WT may initiate a WT Configuration Update (WT Configuration Update) procedure requesting the RN to Update the application layer Configuration data of the WT so that both parties may interact with information normally through the Xw interface. Specifically, the WT sends a WT configuration update message to the RN, where the WT configuration update message carries updated application layer configuration data, and the WT configuration update message includes but is not limited to: add/modify/delete WLAN AP list, which is given by: the new WLAN AP of the WT side, the WLAN AP with changed configuration information of the WT side and the deleted WLAN AP of the WT side. The WLAN AP list gives configuration information for each WLAN AP, including: WLAN Operating Class, WLAN Country Code, capacity (maximum rate supported), supported WLAN band, channel Code, etc.;

(2) the RN may initiate a WT Status Reporting Initiation (WT Status report start) procedure, requesting the WT to perform load measurement. Specifically, the RN sends a WT STATUS REQUEST (WT STATUS REQUEST) message to the WT, where the WT STATUS REQUEST message carries the WLAN AP list. If the WT can perform load measurement of all WLAN APs or part of WLAN APs in the WLAN AP list, the WT feeds back a WT STATUS RESPONSE message to the RN, where the WT STATUS RESPONSE (WT STATUS RESPONSE) message carries a list of WLAN APs that can be measured correctly, and for WLAN APs that cannot perform load measurement, may indicate: the reason why it cannot be measured. If the WT cannot perform any load measurements for WLAN APs, the WT feeds back a WT STATUS FAILURE (WT STATUS FAILURE) message to the RN. For a WLAN AP, the load measurement context includes but is not limited to: uplink/downlink rates, uplink/downlink channel utilization, uplink/downlink channel time utilization, and the like supported by the WLAN AP;

(3) the WT can initiate a WT Status Reporting (WT Status Reporting) process and report the obtained load measurement results of each WLAN AP to the RN;

(4) the RN or WT may initiate an Xw Reset (Xw Reset) procedure. When the sender finds abnormal phenomena, the sender sends an Xw Reset Request message to the receiver, and the receiver RESETs according to the Xw Reset Request message, deletes all relevant configuration data and feeds back a Reset RESPONSE message (RESET) to the sender;

(5) the RN or WT may initiate an Error Indication (Error Indication) procedure. When the receiver finds that the message of the sender has errors, an error indication message is sent to the sender to indicate the reason of the errors.

S201, the RN sends a WT add request message to the corresponding WT over the Xw interface. The WT is the WT corresponding to all APs in the UE's WLAN mobility set.

The WT addition request (WT addition request) message includes: RN UE XwAP ID, WLAN MAC address of UE, first bearer list and WLAN mobile set of UE. An RN UE XwAP ID is an ID distributed to the UE by the RN and used for identifying the UE on an RN side of an Xw interface, a WLAN MAC address of the UE is used for identifying the UE in a process of associating the UE with the WT for receiving the WT addition request message later, and a first bearer list is a list of EPS bearers needing to be diverted to the WLAN and determined by the RN in all EPS bearers of the UE; the WLAN mobility set is a set of WLAN APs with better signal quality around the UE, and these APs are APs under the control of the same WT. The RN sends a WT addition request message to the WT corresponding to all APs in the UE's WLAN mobility set.

For the UE in RRC _ CONNECTED, if the UE indicates that the UE supports the RCLWI in the capability information reported by the UE to the RN, the RN may configure the WLAN measurement for the UE through an RRC connection reconfiguration message. And the UE executes corresponding WLAN measurement according to the WLAN measurement configuration information of the RN. When a WLAN measurement report event is triggered or a WLAN periodic report is triggered, the UE reports a WLAN measurement result to the RN through a measurement report (MeasurementReport) message. The RN determines a WLAN mobile set of the UE according to a WLAN measurement result reported by the UE, wherein the WLAN mobile set is a set of WLAN APs (Access points) with better signal quality around the UE, and the APs are APs controlled by the same WT. Then, the RN dynamically updates the WLAN mobility set of the UE each time the WLAN measurement result reported by the UE is received.

Specifically, the capability information reported by the UE supporting the RCLWI includes WLAN band information and RCLWI capability information, as follows:

a. supported Band List WLAN-r 13: this parameter is only applicable to UEs supporting WLAN for defining WLAN bands supported by the UE.

b. rclwi-r 13: this parameter defines whether the UE supports RCLWI. A UE supporting RCLWI should support WLAN measurements.

For the UE in RRC _ CONNECTED, after the RN reports and acquires the WLAN frequency band information and the RCLWI capability information supported by the UE through the capability of the UE, the RN configures WLAN measurement for the UE. The WLAN measurement configuration procedure is as follows:

first, the RN needs to determine the WLAN measurement object for the UE, i.e.: WLAN APs that the UE needs to measure. Method for determining a WLAN measurement object the invention provides a method for determining a WLAN measurement object for implementation dependent. The method comprises the following steps:

(1) RN summarizes the WLAN AP list of WT with which Xw is successfully established to obtain the total list A.

(2) And the RN finds out the WLAN AP with the frequency point in the WLAN frequency band supported by the UE from the total list A according to the WLAN frequency band information supported by the UE to obtain a list B.

(3) The RN selects WLAN APs from list B that require the UE to perform WLAN measurements, forming list C, where list C is list B or a subset of list B.

Then, the RN needs to determine the following WLAN measurement reporting configuration information, including:

a. the event type triggering the measurement report and all the relevant parameters of the type of event, there are three types of event types triggering the WLAN measurement report: w1, W2 and W3, the RN needs to determine which event to use and the value of the parameter related to the event.

b. The time interval reported in the periodic reporting is as follows: if the periodic measurement reporting is adopted, the RN needs to determine the period of the periodic reporting.

c. The maximum number of cells reported.

d. WLAN measurement reporting amount: for each WLAN AP that needs to be measured, the UE may report the following items of information. The RN needs to determine items that need to be reported by the UE in the following items. For example, the items may include: carrier information, available access capacity, WLAN DL rate, WLAN UL rate, channel utilization, total number of stations associated with the respective WLAN.

Finally, the RN configures WLAN measurement information to the UE through an RRC connection reconfiguration (RRCConnectionReconfiguration) message, and instructs the UE to measure the relevant WLAN APs.

Specifically, the WLAN measurement information carried in the RRC connection reconfiguration message includes the following contents:

(1) list of WLAN measurement objects: the list includes several WLAN measurement object IEs. Each WLAN measurement object IE instructs the UE to measure one WLAN AP. Each WLAN measurement object IE includes the following for configuring relevant information of WLAN APs that need UE measurement:

a. WLAN identifier (BSSID, HESSID and SSID): the measured WLAN AP ID is needed. When the method for determining the WLAN AP is adopted, the WLAN AP indicated by the WLAN identifier is the WLAN AP in the list C.

b. WLAN carrier information: frequency point information employed by the WLAN AP.

c. WLAN band: frequency bands supported by the WLAN AP.

(2) WLAN measurement reporting configuration list: the list includes several WLAN measurement reporting configuration IEs. Each WLAN measurement reporting configuration IE includes the following:

a. and triggering the type of the event reported by the measurement and all relevant parameters of the type of the event.

b. And reporting the time interval in the periodic reporting.

c. The maximum number of cells reported.

d. WLAN measurement overhead IE.

In the 3GPP protocol, there are three WLAN measurement reporting events: w1, W2 and W3. These three measurement reporting events are specified below. Each WLAN measurement reporting event explicitly defines the criteria and related parameters that trigger the UE to report the WLAN measurement. The WLAN measurement reporting configuration IE indicates: and reporting the event by using the measurement in W1, W2 and W3, and giving the value of the relevant parameter of the event.

Event W1: WLAN is better than a threshold.

Event W2: all WLANs in the WLAN mobility set become worse than threshold 1 and one WLAN out of the WLAN mobility set becomes better than threshold 2.

Event W3: all WLANs become worse than a threshold in the WLAN mobility set.

And the UE acquires the WLAN measurement information configured by the RN from the received RRCConnectionReconfiguration message, saves the WLAN measurement information and performs related WLAN measurement. When a given WLAN measurement reporting event is triggered or WLAN periodic reporting is triggered, the UE sends a MeasurementReport message to the RN. In the message, for each reported WLAN AP, the UE carries the measurement result of each measurement item indicated by the WLAN measurement report IE. After configuring the UE with the WLAN measurement, the RN may reconfigure the WLAN measurement to the UE as needed.

When an EPS (Evolved Packet System) bearer is established between the UE and the EPC (Evolved Packet Core), the EPC sends QoS (Quality of Service) information of the EPS bearer to the RN. QOS information for an EPS bearer includes: QCI (QCI: QoS Class Identifier), priority, whether preemption is supported, whether preemption is allowed, MBR and GBR, etc. For the UE that has established an EPS bearer and indicates support of RCLWI in the capability report, the RN may determine, according to the air interface UL/DL remaining resource condition, QOS information of each EPS bearer of the UE, the UE UL/DL channel quality condition, the WLAN measurement result recently reported by the UE, and the latest load measurement report of the WT corresponding to the WLAN mobile set of the UE: whether traffic on certain EPS bearers of the UE is transmitted over the WLAN. When the RN decides to shunt the service on some EPS bearers of the UE to the WLAN, in order to improve the success rate of the service steering to the WLAN, the invention provides: the RN sends a WT addition request message to a corresponding WT first, and applies for a wireless resource to the corresponding WT in advance for traffic diverted to the WLAN.

The configuration information of each EPS bearer in the first bearer list includes: identification of EPS bearer and QoS parameter set. The QoS parameter set includes QCI and Allocation contention Priority (Allocation and contention Priority). For GBR (Guaranteed Bit Rate) traffic, the QoS parameter set also includes GBR QoS information. The GBR QoS information is used for MBR and GBR providing GBR traffic.

S202, the WT determines a second bearer list according to the first bearer list and the WLAN mobility set in the WT add request message. When the second bearer list includes at least one EPS bearer, the WT sends a WT addition request acknowledge message to the RN through the Xw interface. When the second bearer list does not include any EPS bearer, the WT sends a WT addition request reject message to the RN over the Xw interface.

The WT ADDITION REQUEST ACKNOWLEDGE (WT ADDITION REQUEST ACKNOWLEDGE) message carries: RN UE XwAP ID, WT's MAC address, second bearer list, and third bearer list. The WT UE xwwap ID is an ID assigned by the WT to the UE, and is used to identify the UE on the WT side of the Xw interface, the MAC address of the WT is used to identify the WT in the subsequent association process between the UE and the WT, the second bearer list is an EPS bearer list in the first bearer list, to which WLAN radio resources are successfully assigned on the WT side, and the third bearer list is an EPS bearer list in the first bearer list, to which WLAN radio resources cannot be assigned on the WT side. For each EPS bearer in the third bearer list carrying a reason for failing to allocate WLAN resources.

Specifically, the method for determining the second bearer list and the third bearer list in the WT addition request acknowledge message is as follows:

for each EPS bearer in the first bearer list, if the QoS parameter set carried by the bearer includes GBR QoS information, which indicates that the EPS bearer is a GBR bearer, the WT needs to determine whether sufficient WLAN resources can be allocated to the EPS bearer, so as to ensure the QoS of the EPS bearer. And if enough WLAN resources can be allocated to the EPS bearer, adding the EPS bearer into the second bearer list. And if the QoS parameter group carried by the EPS bearer does not contain GBR QoS information, indicating that the EPS bearer is a non-GBR bearer. The WT may determine whether to add the EPS bearer to the second bearer list in the following possible manner.

In a first possible approach, if the WT determines that the non-GBR bearer can be provided with the minimum bit rate, the EPS bearer is added to the second bearer list. The minimum bit rate value is set by the WT, and different minimum bit rates may be configured for non-GBR bearers of different priorities when the minimum bit rate value is set, or the same minimum bit rate may be configured for all non-GBR bearers. The minimum bit rate is used to guarantee the lowest acceptable traffic Experience (QoE) for non-GBR bearers.

In a second possible approach, it is determined whether steering the EPS bearer to WLAN is supported based on the assigned contention priority of the EPS bearer, the WLAN resources remaining for the WT, and the QoS parameter set of the already received traffic. For example: the EPS bearer supports preemption and the priority of the EPS bearer is higher than each service already supported by the WT, and these services already supported all support preemption, then the EPS bearer may be added to the second bearer list.

The embodiment of the present invention is described by taking the above two possible manners as examples, and of course, the determination may be made by other possible manners, and the embodiment of the present invention is not particularly limited as to which manner is specifically adopted.

The second bearer list is determined through the above process, and the EPS bearers which cannot be listed in the second bearer list in the first bearer list constitute a third bearer list. Each EPS bearer in the third bearer list needs to carry the reason for failing to allocate WLAN resources.

When the radio resources on the WT side cannot support EPS bearer steering to WLAN in any of the first bearer lists, the WT feeds back a WT ADDITION REQUEST REJECT (WT ADDITION REQUEST) message. The message carries: RN UE XwAP ID and cause value.

S203, when the RN receives a WT addition request confirmation message through an Xw interface, the RN sends an RRC connection reconfiguration message to the UE. When the RN receives the WT addition request reject message, the RN still sends an RRC connection reconfiguration message to the UE, or the RN returns to step S201 after a certain time interval.

When the RN receives the WT addition request rejection message through the Xw interface, the RN may stop diverting the traffic of the UE to the WLAN, and after a certain period of time, return to step S201, and send the WT addition request message to the corresponding WT again through step S201 to determine whether the WT has enough resources to support the traffic diversion of the UE at this time.

Of course, when the RN receives the addition request rejection message, if the current UL/DL remaining resources of the air interface are limited, or the current several EPS bearers of the UE support preemption, and the RN decides to preempt the resources of these EPS bearers for use by other bearers, the RN may also send an RRC connection reconfiguration message to the UE, and forcibly instruct the UE to switch the related service to the WLAN.

The RRC connection reconfiguration message carries: the traffic steering command. The command includes: an indication to steer to WLAN, WLAN mobility set, MAC address of WT, and fourth bearer list. When the RN receives the WT addition request confirmation message, the fourth bearer list is a second bearer list; when the RN receives the WT addition request reject message, the fourth bearer list is the first bearer list or a subset of the first bearer list.

S204, the UE saves the service steering command in the RRC connection reconfiguration message and sends an RRC connection reconfiguration completion message to the RN.

After receiving the RRC connection reconfiguration message, the UE stores a service steering command in the message: and turning to the indication of the WLAN, the WLAN mobile set, the MAC address of the WT and a fourth bearer list, and sending an RRC connection reconfiguration complete message to the RN to indicate that the RRC connection reconfiguration is completed.

S205, the UE tries to establish connection with the AP in the WLAN mobile set according to the stored service steering command. If the traffic steering command stored by the UE carries the "MAC address of the WT", after the UE establishes a connection with an AP, the UE associates with the corresponding WT according to the MAC address of the WT.

Specifically, the UE starts the WLAN status listening process according to the saved traffic steering command. In the WLAN status listening process, the UE selects one WLAN AP in the WLAN mobility set to initiate a connection establishment request. When it is not possible to connect to the AP, another AP is selected to initiate a connection establishment request until a WLAN AP is successfully connected, after which an association can be established with the WT via the WLAN AP.

It should be noted that, in this embodiment of the present invention, if the UE cannot be connected to any AP in the WLAN mobility set in step S205, the UE may request the RN to continue transmitting the relevant service to be diverted through LTE, where the specific process is as follows:

the UE sends a WLAN Connection Stutus Report message to the RN, and indicates that: the WLAN connection fails.

And after receiving the WLAN connection failure indication sent by the UE, the RN sends an RRC connection reconfiguration message to the UE, wherein the message carries traffic steering command. The command includes: turning to the indication of LTE.

After receiving the RRC connection reconfiguration message, the UE applies for establishing an EPS bearer from the EPC for the services which cannot be transmitted through the WLAN through the LTE according to the carried indication of turning to the LTE, and then transmits corresponding services through the established EPS bearer. When the EPS bearer is established and not released in some services, the UE directly recovers the bearer and transmits the services through LTE through the bearer.

S206, after the UE associates with the WT, the WT sends a WT association confirm message to the RN over the Xw interface.

The WT ASSOCIATION CONFIRMATION (WT ASSOCIATION CONFIRMATION) message includes a WT UE xwwap ID and an RN UE xwwap ID, which are IDs assigned to the UE by the WT and RN, respectively, for identifying the UE on the WT side and the RN side of the Xw interface.

After the WT establishes association with the UE, a WT association confirmation message is sent to the RN, so that the RN determines the UE associated with the corresponding WT according to the WT UE XwAP ID and the RN UE XwAP ID after receiving the confirmation message.

S207, after the UE is associated with the WT, the UE sends a WLAN connection state report message to the RN.

The WLAN Connection status Report (WLAN Connection Stutus Report) message carries: a successful association indication indicating that the UE has successfully connected to the WLAN.

Through the above S206 and S207, the RN determines that the WT and the UE have established an association, and then the UE may transmit the traffic on each EPS bearer in the fourth bearer list in the traffic steering command through the WLAN, so that at the earliest, the RN may release the LTE side resource occupied before each EPS bearer in the fourth bearer list. Of course, the RN may also release the LTE resource occupied by the corresponding bearer in the following step S210.

It should be noted that, in the embodiment of the present invention, the execution main bodies of S206 and S207 are different, there is no sequence between S206 and S207, S206 may be executed first, S207 may be executed first, and of course, S206 and S207 may also be executed simultaneously.

And S208, the UE establishes connection with the EPC through the AP establishing connection.

S209, the UE applies for resources from the EPC for the service corresponding to each EPS bearer in the fourth bearer list through the AP, and establishes the corresponding bearer transmitted through the AP.

And S210, the UE transmits corresponding services through corresponding bearers transmitted through the AP, releases each EPS bearer in the fourth bearer list, and releases LTE side resources occupied by the bearers. Correspondingly, the RN and EPC also release the LTE side resources previously occupied by these bearers.

Before instructing the UE to perform service steering, the method for interworking LTE and WLAN according to the embodiment of the present invention establishes an Xw interface between an RN and a WT, and sends a WT addition request message to the WT through the Xw interface, so that the WT determines a second bearer list according to the first bearer list and a WLAN mobility set, and sends a WT addition request acknowledgement message to the RN through the Xw interface, where the message carries the second bearer list, and each EPS bearer in the second bearer list is a bearer that can provide sufficient resources for the WT side to transmit. When the RN determines that the WLAN has enough resources to bear each EPS bearer in the second bearer list according to the WT addition request confirmation message, the RN sends an RRC connection reconfiguration message to the UE, wherein the message carries the second bearer list, so that after the UE receives the RRC connection reconfiguration message, the UE carries out service steering processing according to the RRC connection reconfiguration message and sends an RRC connection reconfiguration completion message to the RN; and then, the UE tries to establish connection with one AP in the set according to the WLAN mobile set, establishes association with the WT through the AP, and after the association is established, the WT sends a WT association confirmation message to the RN through an Xw interface, and the UE sends a connection state report message to the RN, so that the RN determines that the WT and the UE establish the association according to the two messages. The UE establishes connection with the EPC through the connected AP, applies resources for services needing to be diverted to the WLAN to the EPC through the AP, establishes corresponding load bearing, and transmits the services diverted to the WLAN through the load bearing established by the AP and the EPC. Therefore, the method for interconnecting the LTE and the WLAN, provided by the embodiment of the invention, realizes that the RN shunts the service data of the UE through the WLAN, and improves the service quality of the service diverted to the WLAN.

In addition, for the UE which is in RRC _ CONNECTED in the cell controlled by the RN and supports RCLWI, when the RN turns to LTE from WLAN, the UE traffic is turned to LTE. Optionally, the traffic steering decision information for steering from WLAN to LTE includes, but is not limited to: the condition of the UL/DL residual resources of the cell air interface, the condition of the UL/DL channel quality of the UE in the Uu, the WLAN measurement result reported recently by the UE and the state of the WLAN Connection in the WLAN Connection Stutus Report message sent to the RN by the UE recently. The RN may send a traffic steering to the UE command to the LTE only according to the indication of the WLAN Connection failure in the last WLAN Connection Stutus Report message of the UE. Referring to fig. 4, fig. 4 is a schematic view of another LTE-WLAN interworking method according to an embodiment of the present invention.

S401, the RN sends RRC connection reconfiguration information to the UE, and the information carries a service steering command.

Wherein, the command carries: indication of traffic steering to LTE.

S402, after receiving the RRC connection reconfiguration message, the UE feeds back an RRC connection reconfiguration completion message to the RN.

S403, the UE deletes the stored WLAN mobile set according to the indication of the service steering LTE, and stops the WLAN state monitoring process; and applying for establishing EPS bearing from EPC through RN for each service transmitted through WLAN. And after the EPS bearing is established, transmitting corresponding services through the EPS bearing. When the UE fails to apply for establishing the EPS bearing from the EPC for a certain service through LTE, the UE temporarily terminates the service, and tries to apply for establishing the EPS bearing from the EPC again after a period of time.

In addition, the RN may also carry, in the service steering command in the RRC connection reconfiguration message sent to the UE: releasing the indication of the RCLWI configuration. After receiving the message, the UE deletes the WLAN mobile set according to the indication of releasing the RCLWI configuration, stops the WLAN state monitoring and informs the upper layer that the RCLWI configuration is released.

Fig. 5 is a schematic diagram of an LTE-WLAN interworking system according to an embodiment of the present invention, please refer to fig. 5, where the LTE-WLAN interworking system includes a DeNB, an RN, a WT, and a UE, and the WT hangs up a plurality of APs.

Wherein, the RN is used for establishing an Xw interface with the WT.

The RN is further configured to send a WT add request message to the WT over the Xw interface when the RN determines to divert traffic on some EPS bearers of the UE to the WLAN; the WT add request message includes a first bearer list and a WLAN mobility set; the first bearer list is an EPS bearer list which is determined by the RN in all EPS bearers of the UE and needs to be steered to the WLAN; the WLAN mobility set is a set of APs of the access point with better signal quality around the UE, and all APs in the set of APs correspond to the same WT.

The WT is used for determining a second bearer list according to the first bearer list and the WLAN mobile set and sending a WT addition request confirmation message to the RN through an Xw interface; the WT addition request acknowledgement message includes a MAC address of the WT, a second bearer list, and a third bearer list, where the second bearer list is an EPS bearer list in the first bearer list, to which the WT has successfully allocated WLAN radio resources; the third bearer list is a list of EPS bearers in the first bearer list for which the WT failed to successfully allocate WLAN radio resources.

When the RN receives a WT addition request confirmation message through an Xw interface, the RN is also used for sending an RRC connection reconfiguration message to the UE; the RRC connection reconfiguration message is used for indicating the UE to carry out configuration according to the RRC connection reconfiguration message; the RRC connection reconfiguration message comprises a service steering command; the traffic steering command includes an indication to steer the WLAN, a WLAN mobility set, the WT's MAC address, and a fourth bearer list.

And the UE is used for carrying out service steering according to the RRC connection reconfiguration message.

Optionally, the UE is specifically configured to store the service steering command in the RRC connection reconfiguration message, and send an RRC connection reconfiguration complete message to the RN; the RRC connection reconfiguration complete message is used for indicating the UE configuration completion; the UE tries to establish connection with the AP in the WLAN mobile set in the service steering command; if the traffic steering command stored by the UE carries the MAC address of the WT, the UE is associated with the corresponding WT according to the MAC address of the WT after establishing connection with an AP; establishing connection with the EPC through the AP for establishing connection; applying for resources from the EPC for the service corresponding to each EPS bearer in the fourth bearer list through the AP, and establishing a corresponding bearer transmitted through the AP; and is used to transmit the associated traffic over the bearers transmitted by the AP.

Optionally, the WT is further configured to send a WT association confirmation message to the RN through the Xw interface; the RN is further configured to determine a UE associated with the corresponding WT from the WT association confirm message.

Optionally, the UE is further configured to send a WLAN connection state reporting message to the RN; the connection status reporting message is used for indicating that the UE is connected to the WLAN.

And the RN is also used for determining that the UE is connected to the WLAN according to the connection state reporting message.

Optionally, the RN is specifically configured to send an Xw interface establishment request message to the WT; the Xw interface setup request message includes the RN identity.

The WT is also configured to establish an Xw interface with the RN based on the RN identity.

The WT is further configured to send an Xw interface setup response message to the RN via the Xw interface, where the Xw interface setup response message is used to indicate that the Xw interface setup is successful, and the Xw interface setup response message includes a WT identifier and a WT downlink WLAN AP list.

Optionally, the WT is further configured to send a WT addition request reject message to the RN when the second bearer list does not include any EPS bearer.

In the actual application process, before indicating the UE to perform traffic steering, the RN is used for establishing an Xw interface with the WT and sending a WT addition request message to the corresponding WT through the Xw interface; the WT is configured to determine a second bearer list according to the first bearer list and the WLAN mobility set in the WT addition request message; when the second bearer list comprises at least one EPS bearer, the WT is configured to send a WT addition request acknowledgement message to the RN over an Xw interface; when the second bearer list does not include any EPS bearer, the WT is configured to send a WT addition request reject message to the RN; when receiving a WT addition request confirmation message through an Xw interface, the RN is used for sending an RRC connection reconfiguration message to the UE, wherein a service steering command is carried in the message, and the fourth bearer list is the same as the second bearer list; when receiving a WT addition request rejection message, the RN is configured to send an RRC connection reconfiguration message to the UE, where the message carries a service steering command, where the service steering command carries a fourth bearer list, and the fourth bearer list is the first bearer list or a subset of the first bearer list, or after a period of time, the RN sends a WT addition request message to a corresponding WT through an Xw interface; when receiving the RRC connection reconfiguration message, the UE stores a service steering command in the RRC connection reconfiguration message and sends an RRC connection reconfiguration completion message to the RN; and attempt to establish a connection with an AP in the WLAN mobility set; if the traffic steering command stored by the UE carries the MAC address of the WT, the UE is associated with the corresponding WT according to the MAC address of the WT after establishing connection with an AP; after the UE associates with the WT, the WT is configured to send a WT association confirm message to the RN over the Xw interface; after the UE is associated with the WT, the UE is configured to send a WLAN connection state report message to the RN, establish a connection with the EPC through the AP establishing the connection, apply for a resource from the EPC for a service corresponding to each EPS bearer in the fourth bearer list through the AP, and establish a corresponding bearer transmitted through the AP; and then, the UE transmits corresponding services through corresponding bearers transmitted through the AP, releases each EPS bearer in the fourth bearer list, and releases the LTE side resources occupied by the bearers. Correspondingly, the RN and EPC also release the LTE side resources previously occupied by these bearers.

The LTE-WLAN interworking system can correspondingly implement the technical solution of the LTE-WLAN interworking method according to any embodiment, and the implementation principle and the technical effect are similar, and are not described herein again.

Other embodiments of the disclosure will be apparent to those skilled in the art from consideration of the specification and practice of the disclosure disclosed herein. This application is intended to cover any variations, uses, or adaptations of the disclosure following, in general, the principles of the disclosure and including such departures from the present disclosure as come within known or customary practice within the art to which the disclosure pertains. It is intended that the specification and examples be considered as exemplary only, with a true scope and spirit of the disclosure being indicated by the following claims.

It will be understood that the present disclosure is not limited to the precise arrangements described above and shown in the drawings and that various modifications and changes may be made without departing from the scope thereof. The scope of the present disclosure is limited only by the appended claims.

Claims (8)

1. A method for interconnecting LTE and WLAN, comprising:

the relay node RN and the wireless local area network termination node WT establish an Xw interface;

the RN sends a WT addition request message to the WT through the Xw interface; the WT add request message includes a first bearer list and a WLAN mobility set; the first bearer list is an EPS bearer list which is determined by the RN in all EPS bearers of the UE and needs to be steered to the WLAN; the WLAN mobile set is a set of Access Points (APs) with better signal quality around the UE, and all APs in the AP set correspond to the same WT;

the WT determines a second bearer list according to the first bearer list and the WLAN mobile set and sends a WT addition request acknowledgement message to the RN through the Xw interface; wherein, the WT addition request acknowledge message includes a MAC address of the WT, a second bearer list and a third bearer list, and the second bearer list is an EPS bearer list in which the WT successfully allocated WLAN radio resources in the first bearer list; the third bearer list is an EPS bearer list in the first bearer list for which the WT failed to allocate WLAN radio resources;

when the RN receives a WT addition request confirmation message through the Xw interface, the RN sends a Radio Resource Control (RRC) connection reconfiguration message to the UE; the RRC connection reconfiguration message is used for indicating the UE to carry out configuration according to the RRC connection reconfiguration message; the RRC connection reconfiguration message comprises a service steering command; the traffic steering command includes an indication to steer the WLAN, a WLAN mobility set, a WT's MAC address, and a fourth bearer list;

the UE saves the service steering command in the RRC connection reconfiguration message and sends an RRC connection reconfiguration completion message to the RN; the RRC connection reconfiguration complete message is used for indicating that the UE configuration is complete;

the UE attempting to establish a connection with an AP in the WLAN mobility set in the traffic steering command; if the traffic steering command stored by the UE carries the MAC address of the WT, the UE is associated with the corresponding WT according to the MAC address of the WT after establishing connection with an AP;

the UE sends a WLAN connection state reporting message to the RN; wherein, the connection status report message is used to indicate that the UE is connected to the WLAN;

the RN determines that the UE is connected to the WLAN according to the connection state reporting message;

the UE establishes connection with an EPC through the AP establishing connection;

the UE applies for resources from an EPC for services corresponding to each EPS bearer in the fourth bearer list through the AP, and establishes corresponding bearers transmitted through the AP;

and the UE transmits the service to be diverted through the bearer transmitted by the AP.

2. The method of claim 1, wherein the UE attempts to establish a connection with an AP in a WLAN mobility set; if the traffic steering command stored by the UE carries a WT MAC address, after the UE establishes a connection with an AP and associates with a corresponding WT according to the WT MAC address, the method further includes:

the WT sends a WT association confirmation message to the RN through the Xw interface;

the RN determines a UE associated with a corresponding WT according to the WT association confirmation message.

3. The method according to claim 1, wherein the relay node RN establishes an Xw interface with a wireless local area network termination node WT, comprising:

the RN sends an Xw interface establishment request message to the WT; the Xw interface establishment request message comprises an RN identifier;

the WT establishes the Xw interface with the RN according to the RN identification;

and the WT sends an Xw interface establishment response message to the RN through the Xw interface, wherein the Xw interface establishment response message is used for indicating that the establishment of the Xw interface is successful, and the Xw interface establishment response message comprises a WT identifier and a WLAN AP list hung under the WT.

4. The method of any of claims 1-3, wherein after the WT determines a second list of bearers from the first list of bearers and the WLAN mobility set, further comprising:

when the second bearer list does not include any EPS bearers, the WT sends a WT addition request reject message to the RN.

5. A system for interconnecting LTE and WLAN, comprising: a relay node RN, a wireless local area network termination node WT and user equipment UE;

wherein the RN is used for establishing an Xw interface with the WT;

the RN is further configured to send a WT add request message to the WT over the Xw interface; the WT add request message includes a first bearer list and a WLAN mobility set; the first bearer list is an EPS bearer list which is determined by the RN in all EPS bearers of the UE and needs to be steered to the WLAN; the WLAN mobile set is a set of Access Points (APs) with better signal quality around the UE, and all APs in the AP set correspond to the same WT;

the WT is configured to determine a second bearer list according to the first bearer list and the WLAN mobility set, and send a WT addition request acknowledgement message to the RN through the Xw interface; wherein, the WT addition request acknowledge message includes a MAC address of the WT, a second bearer list and a third bearer list, and the second bearer list is an EPS bearer list in which the WT successfully allocated WLAN radio resources in the first bearer list; the third bearer list is an EPS bearer list in the first bearer list for which the WT failed to allocate WLAN radio resources;

when the RN receives a WT addition request confirmation message through the Xw interface, the RN is also used for sending an RRC connection reconfiguration message to the UE; the RRC connection reconfiguration message is used for indicating the UE to carry out configuration according to the RRC connection reconfiguration message; the RRC connection reconfiguration message comprises a service steering command; the traffic steering command includes an indication to steer the WLAN, a WLAN mobility set, a WT's MAC address, and a fourth bearer list;

the UE is also used for storing a service steering command in the RRC connection reconfiguration message and sending an RRC connection reconfiguration completion message to the RN; the RRC connection reconfiguration complete message is used for indicating that the UE configuration is complete; the UE attempting to establish a connection with an AP in the WLAN mobility set in the traffic steering command; if the traffic steering command stored by the UE carries the MAC address of the WT, the UE is associated with the corresponding WT according to the MAC address of the WT after establishing connection with an AP;

the UE is also used for sending a WLAN connection state report message to the RN; wherein, the connection status report message is used to indicate that the UE is connected to the WLAN;

the RN is also used for determining that the UE is connected to the WLAN according to the connection state reporting message;

the UE is also used for establishing connection with the EPC through the AP for establishing connection; applying for resources to the EPC for the service corresponding to each EPS bearer in the fourth bearer list through the AP, and establishing a corresponding bearer transmitted through the AP; and is used for transmitting the traffic to be diverted through the bearer transmitted by the AP.

6. The system of claim 5,

the WT is further configured to send a WT association confirm message to the RN over the Xw interface;

the RN is further configured to determine a UE associated with the corresponding WT from the WT association confirmation message.

7. The system of claim 5,

the RN is specifically configured to send an Xw interface setup request message to the WT; the Xw interface establishment request message comprises an RN identifier;

the WT is further configured to establish the Xw interface with the RN according to the RN identifier;

the WT is further configured to send an Xw interface setup response message to the RN through the Xw interface, where the Xw interface setup response message is used to indicate that the Xw interface setup is successful, and the Xw interface setup response message includes a WT identifier and a WLAN AP list on which the WT hangs down.

8. The system according to any one of claims 5 to 7,

the WT is further configured to send a WT addition request reject message to the RN when the second bearer list does not include any EPS bearers.

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