CN107343324B

CN107343324B - Method and apparatus for transmitting and receiving data using WLAN radio resources

Info

Publication number: CN107343324B
Application number: CN201610818101.9A
Authority: CN
Inventors: 洪成杓; 崔宇辰
Original assignee: KT Corp
Current assignee: KT Corp
Priority date: 2015-09-24
Filing date: 2016-09-12
Publication date: 2020-12-04
Anticipated expiration: 2036-09-12
Also published as: KR102002203B1; KR20170037493A; CN107343324A

Abstract

The present invention relates to methods and apparatus for processing control plane data to enable an evolved node b (enb) and a User Equipment (UE) to send and/or accept user plane data over a Radio Access Network (RAN) carrier when transmitting user plane data by adding WLAN radio resources to the E-UTRAN carrier at the RAN level. In particular, there is provided a method for a UE to transmit and receive data, the method comprising: receiving Wireless Local Area Network (WLAN) cell configuration information for transmitting and receiving data using WLAN radio resources from an evolved node B (eNB); performing WLAN association based on the WLAN cell configuration information; transmitting a WLAN access confirmation message to the eNB; receiving, from an eNB through higher layer signaling, tunnel configuration information for the UE to establish a tunnel with the eNB through the WLAN radio resources.

Description

Method and apparatus for transmitting and receiving data using WLAN radio resources

Cross Reference to Related Applications

This application claims priority from korean patent application nos. 10-2015-0135795 and 10-2016-0073112, filed 24/9/2015 and 13/2016, which are hereby incorporated by reference in their entirety as if fully set forth herein.

Technical Field

The present invention relates to a method and apparatus for processing control plane data to enable an evolved node b (enb) and a User Equipment (UE) to send and/or accept user plane data over a Radio Access Network (RAN) carrier when transmitting the user plane data by adding WLAN radio resources to the E-UTRAN carrier at the RAN level.

Background

With the development of communication systems, consumers (e.g., companies and individuals) have used various wireless terminals. In addition to providing a voice-based service, a current mobile communication system (e.g., Long Term Evolution (LTE), LTE-advanced (LTE-a), etc.) affiliated to 3GPP may be a high-speed large-capacity communication system capable of transmitting and receiving various data (e.g., image data, wireless data, etc.). Therefore, a technique for transmitting large-capacity data comparable to a wired communication network is desired. As a scheme for transmitting large-capacity data, data can be efficiently transmitted through a plurality of cells.

However, the base station has a limitation in providing a large capacity of data to a plurality of UEs using a limited amount of frequency resources. That is, it is disadvantageous that a high cost is required when a predetermined operator guarantees a dedicated frequency resource.

An unlicensed frequency band that cannot be exclusively used by a predetermined operator or a predetermined communication system may be shared by a plurality of operators or communication systems. For example, a Wireless Local Area Network (WLAN) technology (represented by WiFi) provides data transmission and reception services using frequency resources in an unlicensed frequency band.

Therefore, it is necessary to research a mobile communication system technology for transmitting and receiving data to and from a terminal using a corresponding WLAN Access Point (AP) or the like. In particular, when the base station transmits and receives data to and from the terminal using the WLAN carrier and the base station carrier, its specific procedure and method are not provided, which is a drawback. Furthermore, in order to provide a technology of aggregating LTE and WLAN, it is necessary to study detailed control procedures and data transmission technologies for reusing existing WLAN nodes.

Disclosure of Invention

In this context, an aspect of the present invention provides detailed procedures and techniques for User Equipment (UE) and evolved node b (eNB) to transmit and receive data over an aggregation or combination of WLAN radio resources and eNB carriers.

Further, an aspect of the present invention provides a detailed technique for overcoming the delay problem caused by WLAN access authentication and tunnel setup and the data transmission interruption problem that may occur due to a small WLAN coverage.

According to an aspect of the present invention, there is provided a method for a User Equipment (UE) to transmit and receive data, the method comprising: receiving Wireless Local Area Network (WLAN) cell configuration information for transmitting and receiving data using WLAN radio resources from an evolved node B (eNB); performing WLAN association based on the WLAN cell configuration information; transmitting a WLAN access confirmation message to the eNB; tunnel configuration information for the UE to establish a tunnel with the eNB through WLAN radio resources is received from the eNB through higher layer signaling.

According to an aspect of the present invention, there is provided a method for an eNB to transmit and receive data, the method including: transmitting WLAN cell configuration information for transmitting and receiving data using WLAN radio resources to the UE; receiving a WLAN access confirmation message from the UE; and sending tunnel configuration information for the eNB and the UE to establish a tunnel through the WLAN radio resource to the UE through higher layer signaling.

According to an aspect of the present invention, there is provided a UE for transmitting and receiving data, the UE comprising: a reception unit which receives, from an evolved node B (eNB), WLAN cell configuration information for transmitting and receiving data using WLAN radio resources; a controller that performs WLAN association based on WLAN cell configuration information; a transmitting unit that transmits a WLAN access confirmation message to the eNB, wherein the receiving unit further receives tunnel configuration information for the UE and the eNB to establish a tunnel through WLAN radio resources from the eNB through higher layer signaling after transmitting the WLAN access confirmation message.

According to an aspect of the present invention, there is provided an eNB transmitting and receiving data, the eNB including: a transmission unit that transmits, to the UE, WLAN cell configuration information for transmitting and receiving data using WLAN radio resources; a receiving unit that receives a WLAN access confirmation message from the UE, wherein the transmitting unit further transmits tunnel configuration information for the eNB and the UE to establish a tunnel through WLAN radio resources to the UE through higher layer signaling after receiving the WLAN access confirmation message.

According to the present embodiment described above, the eNB and the UE transmit and receive data through aggregation or combination of WLAN radio resources and eNB carriers, and thus, data processing speed and capacity can be improved.

In addition, the embodiment of the invention can overcome the delay problem caused by WLAN access authentication and tunnel setting and the data transmission interruption problem which can occur due to the small WLAN coverage.

Drawings

The above and other objects, features and advantages of the present invention will become more apparent from the following detailed description taken in conjunction with the accompanying drawings.

Fig. 1 is a diagram illustrating a WLAN radio resource addition procedure based on a tunneling mechanism according to an embodiment of the present invention;

fig. 2 is a diagram illustrating a WLAN radio resource addition procedure based on a tunneling mechanism according to another embodiment of the present invention;

fig. 3 is a diagram illustrating an operation of a UE according to another embodiment of the present invention;

fig. 4 is a diagram illustrating an operation of a User Equipment (UE) according to another embodiment of the present invention, including tunnel setup;

fig. 5 is a diagram illustrating an operation of an evolved node b (enb) according to another embodiment of the present invention;

fig. 6 is a diagram illustrating an operation of an eNB (including tunnel setup) according to another embodiment of the present invention;

fig. 7 is a block diagram illustrating a configuration of a UE according to another embodiment of the present invention; and

fig. 8 is a block diagram illustrating a configuration of an eNB according to another embodiment of the present invention.

Detailed Description

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. When a reference numeral is added to each element in each drawing, the same reference numeral is assigned to the same element as much as possible even if the elements are shown in different drawings. Further, in the following description of the present invention, a detailed description of known functions and configurations incorporated herein will be omitted when it is determined that the subject matter of the present invention may become rather unclear.

In this specification, MTC terminal refers to a low-cost (or not very complex) terminal, a terminal supporting coverage enhancement, and the like. In this specification, an MTC terminal refers to a terminal supporting low cost (or low complexity) and coverage enhancement. Alternatively, in the present specification, an MTC terminal refers to a predetermined kind of terminal defined for maintaining low cost (or low complexity) and/or coverage enhancement.

In other words, in this specification, an MTC terminal may refer to a newly defined low-cost (or low-complexity) UE class/type of 3GPP Release 13, which performs LTE-based MTC-related operations. Alternatively, in this specification, an MTC terminal may refer to a UE class/type that supports enhanced coverage compared to existing LTE coverage, defined in or before 3GPP release-12, or supports low power consumption, or may refer to a low-cost (or low-complexity) UE class/type of newly defined release-13.

A wireless communication system can be widely installed to provide various communication services such as voice service, packet data, etc. A wireless communication system may include a User Equipment (UE) and a base station (BS or eNB). Throughout the specification, the user equipment may be an inclusive concept representing a user terminal used in wireless communication, including UE (user equipment) in WCDMA, LTE, HSPA, etc., and MS (mobile station), UT (user terminal), SS (subscriber station), wireless device, etc., in GSM.

A base station or cell may generally refer to a station that communicates with UEs (user equipments) and may also be referred to as a Node-B (Node-B), an evolved Node-B (enb), a sector, a site, a Base Transceiver System (BTS), an access point, a relay Node, a Remote Radio Head (RRH), a Radio Unit (RU), or the like.

That is, the base station 20 or the cell may be interpreted as an inclusive concept representing a part of an area covered by a BSC (base station controller) in CDMA, a Node B in WCDMA, an eNB or a sector (site) in LTE, or the like, and the concept may include various coverage areas such as a large area, a macro cell, a micro cell, a pico cell, a femto cell, a relay Node communication range, or the like.

Each of the above-mentioned respective cells has a base station controlling the corresponding cell, and therefore, the base station can be interpreted in two ways: i) the base station may be the device itself that provides the large, macro, micro, pico, femto or small cells related to the wireless area; or ii) the base station may represent the wireless region itself. In i), all devices that interact with each other so that a device providing a predetermined wireless zone can be controlled by the same entity or cooperatively configure the wireless zone may be referred to as a base station. An eNB, an RRH, an antenna, an RU, a Low Power Node (LPN), a point, a transmission/reception point, a transmission point, a reception point, etc. may be an embodiment of a base station according to a configuration type of a wireless area. In ii), the wireless area itself that receives or transmits signals may be referred to as a base station from the viewpoint of the terminal or the neighboring base station.

Accordingly, a large cell, a macro cell, a micro cell, a pico cell, a femto cell, a small cell, an RRH, an antenna, an RU, an LPN, a point, an eNB, a transmission/reception point, a transmission point, and a reception point may be collectively referred to as a base station.

In the specification, the user equipment and the base station are used as two inclusive transceiving objects to implement the technology and technical concept described in the specification, without being limited to predetermined terms or words. In the specification, the user equipment and the base station are used as two (uplink or downlink) inclusion type transceiving objects to implement the technology and technical concept described in the specification, and are not limited to predetermined terms or words. Here, Uplink (UL) refers to a scheme in which a UE transmits data to a base station or the base station receives data from the UE, and Downlink (DL) refers to a scheme in which the base station transmits data to the UE or the UE receives data from the base station.

Various multiple access schemes can be applied to the wireless communication system without limitation. Various multiple access schemes may be used, such as CDMA (code division multiple access), TDMA (time division multiple access), FDMA (frequency division multiple access), OFDMA (orthogonal frequency division multiple access), OFDM-FDMA, OFDM-TDMA, OFDM-CDMA, and the like. Embodiments of the present invention can be applied to resource allocation in asynchronous wireless communication schemes evolving from GSM, WCDMA and HSPA to LTE and LTE-a, and can be applied to resource allocation in synchronous wireless communication schemes evolving from CDMA and CDMA-2000 to UMB. The present invention should not be limited to a specific wireless communication field but may include all technical fields to which the technical idea of the present invention can be applied.

The uplink transmission and the downlink transmission may be performed according to a TDD (time division multiplexing) scheme in which transmission is performed based on different times, or may be performed according to an FDD (frequency division multiplexing) scheme in which transmission is performed based on different frequencies.

Further, in systems such as LTE and LTE-a, standards may be developed by configuring uplink and downlink on a single carrier or a pair of carriers. The uplink and downlink may transmit control information through control channels such as PDCCH (physical downlink control channel), PCFICH (physical control format indicator channel), PHICH (physical hybrid ARQ indicator channel), PUCCH (physical uplink control channel), EPDCCH (enhanced physical downlink control channel), etc., and may be configured as data channels such as PDSCH (physical downlink shared channel), PUSCH (physical uplink shared channel), etc., thereby transmitting data.

The control information may be transmitted using EPDCCH (enhanced PDCCH or extended PDCCH).

In this specification, a cell may refer to: a component carrier having a coverage of a signal transmitted from a transmission/reception point (transmission point or transmission/reception point); or the transmission/reception point itself.

The wireless communication system according to the embodiment is: a coordinated multi-point transmission/reception (CoMP) system, a coordinated multi-antenna transmission system, or a coordinated multi-cell communication system in which two or more transmission/reception points coordinate transmission of signals. The CoMP system may include at least two multi-transmission/reception points and a terminal.

The multiple transmission/reception points may be a base station or a macro cell (hereinafter, referred to as "eNB") and at least one RRH connected to the eNB through an optical cable or an optical fiber and wire-controlled, and have high transmission power or low transmission power within a macro cell area.

Hereinafter, downlink refers to a communication or communication path from a plurality of transmission/reception points to a terminal, and uplink refers to a communication or communication path from a terminal to a plurality of transmission/reception points. In the downlink, the transmitter may be part of multiple transmission/reception points, and the receiver may be part of a terminal. In the uplink, the transmitter may be part of a terminal and the receiver may be part of multiple transmit/receive points.

Hereinafter, the case of transmitting and receiving a signal through PUCCH, PUSCH, PDCCH, EPDCCH, PDSCH, etc. may also be described as the expression "transmitting or receiving PUCCH, PUSCH, PDCCH, or PDSCH".

Also, hereinafter, the expression "transmitting or receiving PDCCH, or transmitting or receiving a signal through PDCCH" includes: "transmitting or receiving EPDCCH, or transmitting or receiving a signal through EPDCCH".

That is, the physical downlink control channel used herein may refer to PDCCH or EPDCCH, and may refer to a meaning including both PDCCH and EPDCCH.

Also, for convenience of description, the EPDCCH corresponding to the embodiment of the present invention may be applied to a portion described using the PDCCH, and may refer to a portion described using the EPDCCH.

Meanwhile, the upper layer signaling includes RRC signaling that transmits RRC information including RRC parameters.

The eNB performs downlink transmission to the terminal. The eNB 110 may transmit a Physical Downlink Shared Channel (PDSCH), which is a primary physical channel for unicast transmission, and may transmit a Physical Downlink Control Channel (PDCCH) for transmitting downlink control information, such as: scheduling required to receive the PDSCH, and scheduling grant information for uplink data channel (e.g., Physical Uplink Shared Channel (PUSCH)) transmission. Hereinafter, signal transmission and reception through each channel will be described as transmission and reception of a corresponding channel.

The WLAN carrier in this specification refers to a radio resource using a WLAN, and may be expressed as various terms such as a WLAN radio link, a WLAN radio resource, a WLAN radio network, and the like, as occasion demands. For ease of understanding, in the following description is made by expressing WLAN radio links, WLAN radios, WLAN carriers, WLAN radio networks, etc. as WLAN radio resources.

Furthermore, in this specification, a WLAN terminal denotes a logical WLAN network node. For example, the WLAN terminal may be a WLAN AP or a WLAN AC. The WLAN terminal may be a WLAN network node (e.g. an existing WLAN AP or an existing WLAN AC) or may be a WLAN network node comprising additional functionality for WLAN aggregate transmission (compared to an existing WLAN AP or an existing WLAN AC). The WLAN terminal may be implemented as a separate entity or may be implemented as a functional entity comprised in another entity. Hereinafter, in this specification, a description is made by expressing a WLAN network node as a WLAN terminal or a WLAN AP as occasion demands. Further, in this specification, the description is made by expressing radio resources provided by an eNB as eNB radio resources, an eNB carrier, or an E-UTRAN carrier.

The tunnel entity in this specification means an entity for processing data transmitted and received through an internet protocol security (IPsec) tunnel, and the term is not limited thereto. For example, the tunnel entity may include various terms such as an IPsec tunnel entity, a user data transmission/reception entity using IPsec, a radio bearer-based entity configured at a higher level than the IPsec, an EPS bearer entity, an adaptation entity configured in a layer higher than the tunnel, LTE/WLAN radio level combination using an IPsec tunnel encapsulation protocol (LWIPEP) entity, an IPsec tunnel entity using WLAN, and the like. Hereinafter, for ease of understanding, they are described by being expressed as tunnel entities, it being understood that the tunnel entities include all entities having the same function, and the tunnel entities can be understood from a functional point of view.

Further, in this specification, a tunnel or an IPsec tunnel denotes a tunnel configured between a UE and an eNB for transmitting and receiving data through WLAN radio resources, and may include various terms. For example, an IPsec tunnel may be referred to by various terms such as, but not limited to, a GRE tunnel, a GTP tunnel, an encapsulation-based tunnel, and the like.

The WLAN interworking technology provides RAN-assisted WLAN interworking functions. The E-UTRAN may facilitate UE-based bi-directional traffic direction between the E-UTRAN and the WLAN for UEs in RRC _ IDLE and RRC _ CONNECTED states.

The E-UTRAN provides the UE with assistance parameters through broadcast signaling or dedicated RRC signaling. The RAN assistance parameters may comprise at least one of: an E-UTRAN signal strength threshold, a WLAN channel usage threshold, a WLAN backhaul data transmission rate threshold, a WLAN signal strength { or a WLAN signal strength threshold; such as a beacon RSSI (beacon RSSI) threshold }, or an offload preference indicator. Furthermore, the E-UTRAN may provide the UE with a list of WLAN identifiers through broadcast signaling.

The UE may use RAN assistance parameters for evaluating access network selection and traffic direction rules defined in document TS 36.304 or ANDSF policies defined in document TS 24.312 to determine traffic direction between E-UTRAN and WLAN as specified in "architecture enhancements for non-3 GPP access" for document 3GPP TS 23.402.

When the access network selection and traffic direction rules defined in the document TS 36.304 are satisfied, the UE may indicate the same forwarding to the upper layers of the access stratum.

When the UE employs access network selection and traffic direction rules, the UE may flow control between WLAN and E-UTRAN based on APN granularity units. As described above, the RAN-assisted WLAN interworking function provides only a method in which the E-UTRAN and the WLAN are separately established and work together.

As seen from the above-mentioned limitations with interworking techniques using separate E-UTRAN and WLAN, an LTE-WLAN aggregation technique is desired in which the eNB uses E-UTRAN and WLAN radio resources at the PDCP level. However, using LTE-WLAN aggregation techniques at the PDCP level requires upgrades to existing WLAN APs. For example, in order to generate a tunnel and perform flow control between the eNB and the WLAN node, an existing AP needs to be upgraded. In order to solve the above problem, the present embodiment proposes an LTE-WLAN aggregation technique based on an IPsec tunnel, which can reuse an existing AP. In particular, in order to perform LTE-WLAN aggregation based on IPsec tunnel, a detailed control procedure and a user plane data transmission method performed between the UE and the eNB are required. In particular, unlike an eNB cell, in a WLAN, a large time delay may occur due to access authentication and tunnel setup. For example, there may be a time delay of about 3 to 5 seconds to authenticate using EAP-AKA. A WLAN cell has a smaller coverage area than an eNB cell. Therefore, when the UE moves, the service may be interrupted or data loss may occur, which is a drawback.

As described above, the conventional LTE-WLAN aggregation/bonding method requires upgrading of an existing AP, thereby providing a PDCP-level aggregation technique. Even the LTE-WLAN aggregation/bonding method based on the IPsec tunnel proposed to solve the above-mentioned drawbacks does not provide a detailed control procedure and a user plane data transmission method performed between the UE and the eNB. In particular, time delay caused by performing WLAN access authentication and tunnel setup may increase, and the probability of data transmission interruption due to a small coverage area of a WLAN cell is high, which is a drawback.

The present embodiment, which has been made to overcome the above disadvantages, provides a control procedure and a data transmission method for providing a tunnel-based LTE-WLAN that can reuse existing WLAN APs.

The RRC connected UE may add WLAN radio resources under the control of the eNB. When the eNB desires to add radio resources without additional upgrade to the existing WLAN AP, the eNB establishes a tunnel between the UE and the eNB through the WLAN with respect to the RRC-connected UE and uses the WLAN radio resources. For example, an IPsec tunnel may be configured between the UE and the eNB, and it may be configured over WLAN radio resources. As another example, an IPsec tunnel may be configured between gateways connected to the UE and the eNB, and it may be configured through WLAN radio resources. For this, in the PDCP protocol layer or its higher layers, data can be transferred between the UE and the eNB through the WLAN based on the IPsec tunnel. For example, in a layer lower than the PDCP protocol layer (i.e., PDCP PDU), data can be transferred between the UE and the eNB through the WLAN based on the IPsec tunnel. As another example, in a layer higher than the PDCP protocol layer (i.e., PDCP SDU or IP packet), data can be transferred between the UE and the eNB through the WLAN based on the IPsec tunnel.

Hereinafter, although the description is made by assuming that the IPsec tunnel is configured in a layer higher than the PDCP protocol layer and data is transmitted between the eNB and the UE through the WLAN radio resource, the present invention also includes transmitting data based on the IPsec tunnel in a layer lower than the PDCP protocol layer.

Fig. 1 is a diagram illustrating a WLAN radio resource addition procedure based on a tunneling mechanism according to an embodiment of the present invention.

Referring to fig. 1, an eNB102 requests UE radio access capability transmission for LTE-WLAN aggregation using WLAN radio resources in operation S100. For example, the eNB102 may request UE radio access capability transmission in order to determine whether the respective UE100 supports LTE-WLAN aggregation techniques or in order to determine WLAN band information supported by the UE 100.

In operation S110, the UE100 reports LTE-WLAN aggregation (LWA) capability including WLAN band information supported by the UE 100. The UE100 may have a separate capability bit to indicate that the UE100 supports LTE-WLAN interworking and aggregation functionality. Further, the UE100 may have separate capability bits to indicate that the UE100 supports the aggregation technology, which supports radio bearers (e.g., disjoint bearers) through PDCP in LTE-WLAN aggregation technology, and to indicate that the UE100 supports radio bearers (e.g., tunneled bearers) through tunneling. The UE100 reports LWA capabilities supporting tunnel bearers. Hereinafter, although the description assumes a bearer that transmits and receives data through a WLAN radio resource configuration IPsec tunnel in the LTE-WLAN aggregation technology as a tunnel bearer, the bearer is not limited to this term. That is, the tunnel bearer may be referred to as a handover bearer or the like, and they may be used to refer to the same meaning.

The eNB102 configures WLAN measurements with respect to the UE 100. To this end, the eNB102 includes measurement configuration information, which is required when the UE100 measures WLAN radio resources, in an RRC connection reconfiguration message and transmits it to the UE100 in operation S120.

The UE100 employs the measurement configuration information and transmits an RRC connection reconfiguration complete (rrcconnectionreconfiguration complete) message to the eNB102 in response in operation S130.

The UE100 obtains a WLAN message in operation S140. For example, the UE100 measures WLAN radio resources based on the measurement configuration information described above, and obtains one or more of the following items of information: WLAN association status, WLAN identifier (BSSID/HESSID/SSID), MAC address and IP address.

The UE100 transmits the result of the above-described WLAN measurement to the eNB102 through a measurement report in operation S150. The measurement report may include WLAN status information, such as per WLAN connection status and access quality of WLAN radio resources, measured by the UE100 based on the measurement configuration information.

The eNB102 determines to allocate WLAN radio resources with respect to the predetermined E-RAB and transmits an RRC connection reconfiguration message including new radio resource configuration information to the UE100 in operation S160. The new radio resource configuration information may be determined based on the measurement report information transmitted by the UE100 in operation S150.

The UE100 configures/applies new radio resource configuration information for the UE100 for using the WLAN radio resources based on the RRC connection reconfiguration message. The new radio resource configuration information used when the UE100 uses WLAN radio resources may include one or more of the following items of information: WLAN cell configuration information, WLAN split bearer configuration information using a WLAN split bearer of the WLAN cell, and WLAN tunnel bearer configuration information. The WLAN separated bearer configuration information refers to configuration information related to a bearer type for transmitting data by simultaneously using the WLAN radio resource and the LTE radio resource. The WLAN tunnel bearer configuration information refers to configuration information related to a bearer type for transmitting data using the IPsec tunnel through the WLAN radio resource.

Hereinafter, for convenience of explanation, description will be made using a tunnel bearer as an example. However, examples of configuring the WLAN split bearer are also included within the scope of the present invention.

The WLAN cell configuration information may include one or more of the following: WLAN cell identifier information, WLAN mobility set information, WLAN band/frequency information, and WLAN identification information (BSSID/HESSID/SSID). Alternatively, the WLAN cell configuration information may include: information indicating a cell to which WLAN access authentication is to be performed among WLAN cells. For example, the WLAN cell configuration information may include one or more of the following: the information indicating WLAN access authentication in a predetermined cell, the information indicating a cell in which data transmission is to be performed through WLAN radio resources among WLAN cells, and the information indicating a WLAN primary cell. The information indicating the cell for which WLAN access authentication is to be performed may indicate: information indicating a cell to be added to a WLAN mobility set. Based on the information indicating the WLAN access authentication cell or the information indicating the cell in which WLAN data transmission is to be performed, the UE100 may perform access authentication through the corresponding cell. Unlike the above, when the UE100 successfully performs access authentication for the WLAN cell in operation S140 and the eNB102 knows the successful access authentication state through operation S150, the eNB102 may transmit WLAN cell configuration information to the UE100 without including information indicating that WLAN access authentication is required in the corresponding cell. For example, information indicating WLAN cells to be released from the WLAN mobility set may be included and transmitted.

The tunnel bearer configuration information or the tunnel configuration information may include at least one of the following: an IP address of the eNB102 or an IP address of a gateway (to be used for establishing a tunnel between the UE100 and the eNB102 through WLAN radio resources) connected with the eNB 102; eps carries identification information (eps-bearer identity); tunnel entity configuration information (e.g., an entity having at least one of IPsec bearer encapsulation/decapsulation, IPsec security association, and key exchange), security information, tunnel endpoint identification information of the eNB, DRB identification information (DRB-Identity) of a DRB using the IPsec tunnel over WLAN radio resources, tunnel endpoint identification information of the UE.

The UE100 applies the new radio resource configuration information and transmits an rrcconnectionreconfiguration complete message to the eNB102 in response in operation S170.

Hereinafter, the data may represent only user plane data in a narrow sense, or may represent data including control plane data in a broad sense.

The UE100 performs a WLAN association operation in operations S180 and S185.

For example, the UE100 performs WLAN association with the WLAN node 101.

As another example, the UE100 performs WLAN access authentication with the WLAN node 101 (e.g., WLAN AP/AC/terminal). This may be done by an access authentication procedure between the UE100 and the 3GPP core network entity 103(AAA/HSS or 3GPP AAA proxy) defined in 3GPP TS 33.402. The AAA/HSS 103 and/or the 3GPP AAA proxy use an IP address (or IPv6 prefix; hereinafter, for convenience of explanation, an IP address is used, and in this case, the IP address includes an IPv6 prefix) allocated by the WLAN node for successful authentication. After authentication, the UE100 may be configured based on the IP address assigned from the WLAN node 101. The IP address may be used to send a message for establishing an IPsec tunnel with the UE100 or may be used as the source address of the outer header of the IPsec tunnel between the UE100 and the eNB 102. The UE100 and eNB102 enable the eNB102 to identify the IP address of the UE100 to establish the IPsec tunnel over WLAN radio resources. For example, the AAA/HSS 103, the 3GPP AAA proxy, the 3GPP core network entity (MME, PGW), or the core network entity including the DHCP server function may transmit the IP address of the UE100 (which is allocated/updated/released from the WLAN node 101 when the UE IP address is allocated/updated/released) to the eNB 102. As another example, when the UE100 is allocated an IP address from the WLAN node 101 based on the radio resource configuration of the eNB102 as in operation S160, the UE100 includes the IP address of the UE100 allocated from the WLAN node 101 in an RRC message (e.g., a WLAN status/information message) and transmits it to the eNB102 through an interface (e.g., Uu interface) between the UE100 and the eNB 102. Further, when the UE100 is released from association with the WLAN node 101 and the IP address is released, the UE100 may report it to the eNB 102. As another method, the UE100 includes an IP address of the UE100 allocated from the WLAN node 101 in the MAC CE and transfers it to the eNB102 through an interface (Uu) between the UE100 and the eNB 102.

As another example, a WLAN between the UE100 and the eNB102 may be performed to perform an access authentication procedure. The eNB102 may use the IP address (or IPv6 prefix) assigned from the WLAN node 101 for successful authentication. For example, when the UE100 requests an IP address (or IPv6 prefix) through DHCP protocol or the like, the WLAN node 101 may request an IP address (or IPv6 prefix) on the authentication and authorization message from the eNB 102. To enable the WLAN node 101 to perform an address allocation operation by the eNB102, the UE100 transmits information (e.g., DHCP option information) indicating this to the WLAN node 101. The information indicating that the WLAN node 101 needs UE IP address allocation through the eNB102 may be included in the rrcconnectionreconfiguration message in operation S160 and may be transmitted to the UE 100. The eNB102 specifies an IP address (or IPv6 prefix) to be allocated by the corresponding WLAN node 101 based on information (e.g., one or more of WLAN node identification information, candidate IP address (or IPv6 prefix), and version information) on the authentication and authorization message requested by the WLAN node 101 from the eNB102, and provides it to the WLAN node 101. The WLAN node 101 provides the UE100 with an IP address (or IPv6 prefix). After authentication, the UE100 may be configured based on the IP address assigned from the WLAN node 101. The IP address may be used to send a message for establishing an IPsec tunnel with the UE100 or may be used as the source address of the outer header of the IPsec tunnel between the UE100 and the eNB 102.

Upon completion of the WLAN association of the UE100, the UE100 may begin an Internet Key Exchange (IKE) establishment procedure. The IP address of the eNB102 or the IP address of the gateway connected to the eNB102 required when the UE100 establishes the IPsec tunnel may be provided by being included in the rrcconnectionreconfiguration message of operation S160. Alternatively, the tunnel configuration information and the tunnel bearer configuration information for establishing the tunnel may be received from the eNB102 when the WLAN association of the UE100 is completed.

In the above description, an example of a detailed method for a UE to configure a tunnel with an eNB through WLAN radio resources has been provided with reference to the accompanying drawings.

As described above, the WLAN configures a smaller cell coverage than the eNB cell, and may require time for WLAN access authentication and tunnel establishment, thereby enabling the UE to use WLAN radio resources. Therefore, there may be a time delay in data transmission and reception using the eNB radio resources and data transmission and reception using the tunnel established through the WLAN radio resources. Accordingly, in addition to the tunnel establishment and access authentication procedure using WLAN radio resources, which has been described with reference to fig. 1, various access authentication and tunnel establishment procedures may be considered. In the following, various embodiments relating to WLAN access authentication, tunnel establishment and bearer configuration procedures will be described.

The first embodiment: controlling activation after configuring bearers using WLAN radio resources to inactive state Method of producing a composite material

As described above, after transmitting the WLAN measurement report to the eNB, the UE may receive configuration information for applying the new radio configuration from the eNB.

For example, the UE receives an rrcconnectionreconfiguration message from the eNB and may apply new radio configuration information included in the corresponding message to the UE.

For example, the UE may configure a tunnel entity that controls data transmission/reception using a tunnel to be in a disabled (suspended or disabled) state until data transmission through the WLAN radio resource can be performed based on WLAN access authentication and tunnel establishment. That is, the UE may configure the tunnel entity to be in a failure state until operation S180 or S185 or S190 in fig. 1. Alternatively, the UE may configure the tunnel entity to be in a failed state until operations S180, S185, or S190 are successfully performed after the predetermined timer is started.

In particular, the UE may configure the tunnel entity based on the new radio resource configuration information and may deactivate the tunnel entity. When a tunnel entity fails, downlink data transmission or uplink data transmission through the WLAN radio resource with respect to a tunnel bearer using the tunnel entity may fail.

The eNB may know whether WLAN access authentication or tunnel establishment succeeded or failed. The eNB may identify success or failure in WLAN access authentication or tunnel establishment with the UE, or may determine success or failure by receiving success or failure information related to WLAN access authentication or tunnel establishment from the UE. When the UE successfully performs WLAN access authentication or tunnel establishment, the eNB activates (recovers or enables) the failed tunnel bearer, and transmits and receives user data. To this end, the eNB may transmit indication information for activating the failed tunnel bearer to the UE.

The eNB may send/receive data to/from the UE through the E-UTRAN bearer until the tunnel bearer is configured to fail or the failed tunnel bearer is activated. Next, the eNB may change the E-UTRAN bearer to a tunnel bearer and may configure the tunnel bearer for the UE for data transmission through an RRCConnectionReconfiguration message, a MAC CE, or indication information for indicating activation. Through the above, the problem of data transmission interruption caused by time delay during WLAN access authentication or tunnel establishment can be overcome.

As another example, the UE configures a WLAN cell based on the new radio resource configuration information and may deactivate the WLAN cell. When a WLAN cell fails, downlink data transmission or uplink data transmission through the WLAN radio resource for a tunnel bearer connected with the corresponding WLAN cell becomes failed. The eNB activates the failed WLAN cell and transmits/receives user data through a tunnel bearer connected with the WLAN cell. The eNB may transmit indication information for activating the failed WLAN cell to the UE.

As another example, in a state where a WLAN cell or a tunnel bearer connected with the corresponding WLAN cell fails, user data transmission fails. However, it may be configured such that: transmission of control data, such as WLAN access authentication and tunnel establishment (tunnel mechanism establishment), may be performed. With the above, WLAN access authentication and tunnel mechanism establishment is possible. For example, the eNB may transmit/receive data to/from the UE through the E-UTRAN bearer until the WLAN cell is activated or the failed tunnel bearer is activated. Next, the eNB may change the E-UTRAN bearer to a tunnel bearer and may transmit data through an RRCConnectionReconfiguration message, a MAC CE, or information for activation indication.

According to the above embodiments of the present invention, the UE configures the WLAN cell, the tunnel entity and the tunnel bearer based on the radio resource configuration information received from the eNB and keeps them disabled until the tunnel establishment and the WLAN access authentication are completed. Next, when tunnel establishment and WLAN access authentication are completed, data transmission/reception may be performed through the tunnel based on an activation indication or a bearer change indication from the eNB.

Second embodiment: method for configuring tunnel bearer after tunnel establishment

As indicated above, after transmitting the WLAN measurement report to the eNB, the UE may receive configuration information from the eNB for assuming the new radio configuration. For example, the UE receives an rrcconnectionreconfiguration message from the eNB and applies new radio resource configuration information included in the corresponding message to the UE.

The new radio resource configuration information for using the WLAN radio resources may include WLAN cell configuration information. The WLAN cell configuration information may include at least one or more of the following: WLAN cell identifier information, WLAN mobility set information, WLAN band/frequency information, and WLAN identification information (BSSID/HESSID/SSID). Alternatively, in connection with a cell to which WLAN access authentication is to be performed among the WLAN cells, information indicating a corresponding WLAN cell to which WLAN access authentication is to be performed may be included. Alternatively, information indicating a cell (e.g., a primary cell) in which data transmission is to be performed through WLAN radio resources among WLAN cells may be included.

Alternatively, the new radio resource configuration information for using the WLAN radio resource may include: information indicating WLAN access authentication and tunnel configuration information for configuring a tunnel (e.g., IPsec tunnel) through WLAN radio resources. The tunnel configuration information may include at least one of the following: an IP address of an eNB or an IP address of a gateway connected to the eNB, a key value, security association/negotiation information, an encryption algorithm, and authentication method information, which are required to establish the IPsec tunnel.

When receiving information indicating a WLAN access authentication cell or information indicating a cell in which WLAN data transmission is to be performed, which is included in the WLAN cell configuration, the UE may perform access authentication through the corresponding WLAN cell. Alternatively, the eNB may transmit a MAC CE enabling the UE to attempt access authentication for the WLAN access authentication cell, and the UE may receive the corresponding MAC CE and perform access authentication for the WLAN access authentication cell.

Next, the UE establishes a tunnel with the eNB through the WLAN radio resources based on the tunnel configuration information. In the process of establishing the tunnel through the WLAN radio resource, at least one piece of information among a key value, security association/negotiation information, a ciphering algorithm, and an authentication method may be included in the RRC message and may be transmitted or received through a Uu interface between the UE and the eNB. Alternatively, at least one of key value, security association/negotiation information, encryption algorithm, and authentication method may be transmitted or received in a path using WLAN radio resources in the process of establishing the tunnel.

When the tunnel is successfully established, the eNB transmits an RRCConnectionReconfiguration message including tunnel bearer configuration information to the UE. The RRCConnectionReconfiguration message including the tunnel bearer configuration information may be a different message from the message including the WLAN access authentication indication information and the tunnel configuration information. That is, first, the UE receives the WLAN cell configuration information and the tunnel configuration information and performs WLAN access authentication and tunnel establishment, and then, the UE may additionally receive the tunnel bearer configuration information.

For example, the tunnel bearer configuration information includes one or more of the following information: esp bearer identification information (eps-bearer Identity) for each tunnel bearer, tunnel entity configuration information, security information, tunnel endpoint identification information of the eNB, DRB identification information (DRB-Identity), and tunnel endpoint identification information of the UE. A tunnel entity refers to an entity that handles one or more of the following operations: IPsec header encapsulation/decapsulation, IPsec security association, and key exchange.

After configuring the tunnel bearer, the UE transmits an rrcconnectionreconfiguration complete message as a response. For example, the eNB may transmit/receive data to/from the UE through the E-UTRAN bearer until tunnel establishment is completed or successfully performed. Next, the eNB may change the E-UTRAN bearer to a tunnel bearer through the RCConnectionReconfiguration message, and may use the tunnel bearer.

The above description provides a method in which the UE completes WLAN access authentication and tunnel establishment using WLAN cell configuration information and tunnel configuration information included in radio resource configuration information received from the eNB, additionally receives tunnel bearer configuration information, and performs data transmission/reception using a tunnel bearer. Through the above, the UE transmits/receives data to/from the eNB through the E-UTRAN bearer until the tunnel bearer is configured, and thus, a data interruption problem can be overcome.

The third embodiment: method for simultaneously establishing tunnel bearer and E-UTRAN bearer associated therewith

As described above, after transmitting the WLAN measurement report to the eNB, the UE may receive configuration information for applying the new radio configuration from the eNB. For example, the UE receives an rrcconnectionreconfiguration message from the eNB and may apply new radio resource configuration information included in the corresponding message to the UE.

The new radio resource configuration information for using the WLAN radio resources may include WLAN cell configuration information and tunnel bearer configuration information. Further, the radio resource configuration information may include E-UTRAN bearer configuration information of E-UTRAN associated with the tunnel bearer. The WLAN cell has a smaller coverage area than the E-UTRAN cell and it is difficult to control radio resources. Accordingly, the eNB includes E-UTRAN bearer configuration information (DRB-ToAddMode) of an E-UTRAN bearer (fallback bearer) using the E-UTRAN cell in conjunction with the tunnel bearer in the radio resource configuration information and enables the E-UTRAN bearer to be configured for the UE so that the UE can rapidly handover the bearer when a problem occurs in the WLAN radio link. The UE identifies the predetermined radio bearer as an E-UTRAN bearer associated with the tunnel bearer based on one of: eps-bearer identification information (eps-bearer Identity), DRB identification information (DRB-Identity), and indication information indicating a bearer associated with the tunnel bearer.

For example, the UE may send and receive data over an E-UTRAN bearer associated with the tunneled bearer until data transmission over WLAN radio resources according to WLAN access authentication and tunneling establishment. The UE may disable the E-UTRAN bearer (or bearer RLC/PDCP entity) when data transmission can be made over the WLAN radio resources after WLAN cell authentication. The RLC entity and the PDCP entity can be reconfigured when the E-UTRAN bearer fails.

As another example, the UE may deactivate an E-UTRAN bearer (or bearer RLC/PDCP entity) associated with the tunnel bearer until the UE detects a failure from the WLAN radio link or the UE releases the tunnel bearer. The UE may activate an E-UTRAN bearer associated with the tunnel bearer when the UE detects a failure from the WLAN radio link.

As another example, the eNB may transmit information indicating a bearer to be used among E-UTRAN bearers associated with the tunnel bearer to the UE. The UE may receive or transmit data through a corresponding bearer entity based on the indication information.

The failure in the WLAN radio link may refer to one or more of the following: a condition where the quality of the WLAN radio link (e.g., beacon RSSI, channel utilization, backhaul rate, WLAN signal strength) is below a predetermined threshold; a condition that the quality of the WLAN radio link is below a predetermined threshold for a predetermined period of time; a case where no feedback for WLAN transmissions is received within a predetermined period of time; detecting at least a predetermined amount of loss from feedback for the WLAN transmission; and the case where the WLAN access authentication is not successfully performed within a predetermined period of time.

In the embodiments provided in the above description, the eNB transmits WLAN cell configuration information for WLAN access authentication and tunnel bearer configuration information and associated E-UTRAN bearer configuration information for configuring a tunnel bearer to the UE, and the UE prevents data loss using the E-UTRAN bearer associated with the tunnel bearer.

Fourth embodiment: method for receiving tunnel bearer configuration information after WLAN access authentication

As described above, after transmitting the WLAN measurement report to the eNB, the UE may receive configuration information for applying the new radio configuration from the eNB. For example, the UE receives an rrcconnectionreconfiguration message from the eNB and applies new radio resource configuration information included in the corresponding message to the UE.

The new radio resource configuration information for using the WLAN radio resources may include WLAN cell configuration information. Alternatively, the new radio resource configuration information or WLAN cell configuration information may include information indicating WLAN access authentication. For example, the WLAN cell configuration information may include one or more of the following: WLAN cell identifier information, WLAN mobility set information, WLAN band/frequency information, and WLAN identification information (BSSID/HESSID/SSID). In relation to a cell for which WLAN access authentication is to be performed among WLAN cells, information indicating a corresponding cell in which WLAN access authentication is to be performed may be included. Alternatively, information indicating a cell (e.g., a primary cell) to be subjected to data transmission through WLAN radio resources among WLAN cells may be included.

When the UE receives information indicating a WLAN access authentication cell or information indicating a cell in which WLAN data transmission is to be performed, which is included in a WLAN cell configuration, the UE may perform access authentication through the corresponding WLAN cell. Alternatively, in case the eNB transmits a MAC CE (which enables the UE to attempt access authentication for the WLAN access authentication cell), the UE may perform access authentication for the WLAN access authentication cell when the UE receives the corresponding MAC CE.

The eNB may determine whether the UE successfully performs access authentication in a WLAN access authentication procedure of the UE. Alternatively, the eNB may determine that WLAN access authentication of the UE is successfully performed by receiving successful WLAN access authentication information from the UE. To this end, when WLAN access authentication of the UE is successfully performed, the UE may transmit a WLAN access confirm message to the eNB.

After determining that the WLAN access authentication of the UE is successfully performed, the eNB transmits to the UE an RRCConnectionReconfiguration message including at least one of tunnel configuration information and tunnel bearer configuration information for establishing a tunnel. The RRCConnectionReconfiguration message including the tunnel configuration information and/or the tunnel bearer configuration information may be transmitted through a message different from a message transmitting the WLAN cell configuration information (including the WLAN access authentication indication information).

When the UE receives higher layer signaling (e.g., an rrcconnectionreconfiguration message) including tunnel configuration information and/or tunnel bearer configuration information, the UE may establish a tunnel with the eNB through WLAN radio resources based on the tunnel configuration information, may configure a tunnel bearer, and may transmit an acknowledgement message to the eNB. The acknowledgement message may be included in the RRCConnectionReconfigurationComplete message.

Alternatively, when the UE receives higher layer signaling including tunnel configuration information and/or tunnel bearer configuration information, the UE adopts the corresponding configuration information and transmits an rrcconnectionreconfiguration complete message to the eNB. Next, the UE establishes a tunnel based on the tunnel configuration information. Further, when a WLAN radio link is in problem during tunnel establishment, the UE may report it to the eNB through an RRC message.

For example, the eNB may send/receive data to/from the UE over the E-UTRAN bearer until WLAN access authentication is completed or successfully performed. Next, the eNB may provide an indication to convert the E-UTRAN bearer into a tunnel bearer and transmit data through an RRCConnectionReconfiguration message or a MAC CE. The UE may send/receive data using the IPsec tunnel over the WLAN radio resources for the tunnel bearer.

As described above, in the present embodiment, WLAN cell configuration information for WLAN access authentication and higher layer signaling for establishing a tunnel and for configuring a tunnel bearer may be sequentially transmitted. Meanwhile, as described above, after the WLAN access authentication of the UE is successfully completed, the UE and the eNB may use the WLAN radio resource for data transmission/reception without interruption by configuring the indication of the tunnel bearer.

Hereinafter, the operation of the fourth embodiment will be described in detail with reference to the accompanying drawings.

Fig. 2 is a diagram illustrating a WLAN radio resource addition procedure based on a tunneling mechanism according to another embodiment of the present invention.

The UE100 in the present embodiment receives measurement configuration information for measuring the WLAN from the eNB102 in operation 200. The measurement configuration information may be received by being included in higher layer signaling. For example, the measurement configuration information may be received by being included in an RRC connection reconfiguration message. The measurement configuration information may include parameters for measuring WLAN cells required when the UE100 and the eNB102 use WLAN radio resources for data communication. That is, the eNB102 configures the WLAN measurement operation for LTE-WLAN aggregation for the UE through the RRC connection reconfiguration message.

In operation S210, the UE100 configures the received measurement configuration information for the UE100 and transmits a response message to the eNB 102. The response message may be an RRC connection reconfiguration complete message.

Next, in operation S220, the UE100 reports the result of the WLAN measurement (measurement based on the measurement configuration information) to the eNB 102. The eNB102 configures the UE100 for LTE-WLAN aggregation techniques based on WLAN measurement information received from the UE 100.

In operation S230, the eNB102 transmits WLAN cell configuration information for transmitting/receiving data using WLAN radio resources to the UE 100. The WLAN cell configuration information may be transmitted to the UE100 by being included in an RRC connection reconfiguration message. The WLAN cell configuration information may include at least one of WLAN mobility set information and WLAN identification information. Further, the WLAN cell configuration information may include information related to a WLAN cell (e.g., indication information indicating the WLAN cell) on which the UE100 is to perform an access authentication operation.

In operation S240, the UE100 applies the WLAN cell configuration information to the UE100 and transmits a response message to the eNB 102. The response message may be included in the RRC connection reconfiguration complete message.

In operation S250, the UE100 performs a WLAN association operation based on the received WLAN cell configuration information. WLAN association operations may be performed between the WLAN node 101 and the UE 100. Through the WLAN association operation, the UE100 can successfully access the WLAN. The various WLAN access authentication operations described with reference to fig. 1 may be employed as WLAN association operations.

In operation S260, the UE100 transmits WLAN connection state information to the eNB102 based on the performance of the WLAN association operation. For example, when the UE100 completes WLAN access authentication, the UE100 sends information confirming WLAN association to the eNB 102. The eNB102 may use the received WLAN connection status information to determine whether the UE100 successfully accessed the WLAN node 101.

In operation S270, the eNB102 receives WLAN connection state information from the UE100 and transmits tunnel configuration information for establishing a tunnel between the UE100 and the eNB102 using WLAN radio resources. The tunnel configuration information may be transmitted to the UE100 by being included in higher layer signaling (e.g., RRC connection reconfiguration message). The tunnel configuration information may include parameter information required to configure the IPsec tunnel. Alternatively, the eNB102 may also include the tunnel bearer configuration information in the higher layer signaling of operation S270 and may transmit it. The tunnel bearer configuration information may include bearer identification information associated with a bearer configured to transmit/receive data using the tunnel. For example, the tunnel bearer configuration information may include DRB identification information associated with a DRB configured to use the tunnel.

The UE100 receives higher layer signaling including tunnel configuration information or tunnel bearer configuration information, will configure it for the UE100, and transmits a response message to the eNB102 in operation S280. The response message may be included in the RRC connection reconfiguration message.

In operation S290, the UE100 establishes an IPsec tunnel with the eNB102 through the WLAN radio resources based on the tunnel configuration information, and transmits/receives data of a radio bearer based on the tunnel bearer configuration information using the IPsec tunnel.

As described above, the UE100 can transmit/receive data by establishing an IPsec tunnel with the eNB102 using WLAN radio resources using higher layer signaling. Further, after the WLAN association is successfully performed using the information for the WLAN access authentication, the UE100 receives the information for establishing the tunnel and for configuring the tunnel bearer and configures it for the UE100, thereby minimizing a delay time caused by the access authentication and the tunnel establishment. That is, a data transmission/reception operation through the tunnel may be directly performed after the tunnel is set without additional operations, such as disabling the tunnel entity during a time delay caused by WLAN access authentication.

Hereinafter, the operation of the fourth embodiment will be described from the perspective of the UE and the eNB.

Fig. 3 is a diagram illustrating an operation of a UE according to another embodiment of the present invention.

The UE according to the embodiment of the invention comprises: an operation of receiving Wireless Local Area Network (WLAN) cell configuration information for transmitting/receiving data using WLAN radio resources from an eNB in operation S310. As described above, the WLAN cell configuration information includes parameters required when the UE accesses the WLAN cell. For example, the WLAN cell configuration information may include one or more of the following: WLAN cell identifier information, WLAN mobility set information, WLAN band/frequency information, and WLAN identification information (BSSID/HESSID/SSID). Alternatively, the WLAN cell configuration information may include information indicating a cell for which WLAN access authentication is to be performed among WLAN cells. For example, the WLAN cell configuration information may include one or more of the following: information indicating WLAN association authentication in a predetermined cell, information indicating a cell in which data transmission is to be performed through WLAN radio resources among WLAN cells, and information indicating a WLAN primary cell.

The UE includes performing a WLAN association operation based on the WLAN cell configuration information in operation S320. And the UE performs access authentication operation aiming at the WLAN cell based on the WLAN cell configuration information. The WLAN cell on which the access authentication operation is to be performed may be specified through WLAN cell configuration information or may be specified through a MAC CE received from the eNB. Alternatively, the WLAN cells may be designated by other various methods.

Next, the UE includes an operation of transmitting a WLAN access confirm message to the eNB in operation S330. When the WLAN access authentication is completed, the UE may transmit a WLAN connection status report including information associated with the WLAN access status to the eNB in operation S320. The eNB determines whether the UE completes WLAN access authentication or fails WLAN access authentication based on the received WLAN connection status report.

The UE includes an operation of receiving tunnel configuration information for establishing a tunnel between the eNB and the UE through WLAN radio resources from the eNB through higher layer signaling in operation S340. For example, when WLAN access authentication is completed, the UE may receive parameters required for establishing a tunnel using WLAN radio resources from the eNB. The parameter may be received by being included in the tunnel configuration information and may be received by an RRC connection reconfiguration message.

The higher layer signaling including the tunnel configuration information may further include configuration information for configuring a radio bearer using the tunnel. The tunnel bearer configuration information may include DRB identification information related to a DRB configured to transmit/receive data using a tunnel. The UE may configure a radio bearer, among the radio bearers, designated based on the DRB identification information, as a radio bearer using the tunnel.

Through the above, the UE configures a tunnel with the eNB using the WLAN radio resources and transmits/receives data by minimizing a time delay associated with WLAN access authentication.

Fig. 4 is a diagram illustrating an operation of a User Equipment (UE) including tunnel setup according to another embodiment of the present invention.

Referring to fig. 4, the UE further includes an operation of establishing an internet protocol security (IPsec) tunnel through a WLAN radio resource based on the tunnel configuration information and transmitting/receiving data to/from the eNB using the IPsec tunnel in operation S450. Operations S310 to S330 are performed in the same manner as described in fig. 3, and thus, a detailed description thereof will be omitted.

The UE establishes an IPsec tunnel with the eNB using the tunnel configuration information of the higher layer signaling received in operation S340. Further, the UE may configure the radio bearer using the IPsec tunnel based on the tunnel bearer configuration information.

The UE may transmit/receive data of a tunnel bearer to/from the eNB using an IPsec tunnel (which is set using WLAN radio resources). To this end, a tunnel bearer may be associated with the tunnel entity, and the tunnel entity adds an IPsec header to data of the upper layer and transmits it to the lower layer, and removes the IPsec header from data received from the lower layer and transmits it to the upper layer.

Fig. 5 is a diagram illustrating an operation of an evolved node b (enb) according to another embodiment of the present invention.

Referring to fig. 5, the eNB includes an operation of transmitting Wireless Local Area Network (WLAN) cell configuration information for transmitting/receiving data using WLAN radio resources to the UE at operation S510. The WLAN cell configuration information includes parameters required when the UE accesses the WLAN cell. For example, the WLAN cell configuration information may include one or more of the following messages: WLAN cell identifier information, WLAN mobility set information, WLAN band/frequency information, and WLAN identification information (BSSID/HESSID/SSID). Alternatively, the WLAN cell configuration information may include information indicating a cell for which WLAN access authentication is to be performed among WLAN cells. For example, the WLAN cell configuration information may include one or more of the following: information indicating WLAN association authentication in a predetermined cell, information indicating a cell in which data transmission is to be performed through WLAN radio resources among WLAN cells, and information indicating a WLAN primary cell. The eNB transmits WLAN cell configuration information required when the UE performs an access authentication operation for the WLAN cell, separately from the tunnel configuration information in advance.

Further, the eNB includes an operation of receiving a WLAN access authentication message from the UE in operation S520. And the UE performs association operation for the WLAN cell based on the WLAN cell configuration information and sends information related to the WLAN cell access state to the eNB. The eNB determines a WLAN cell access status of the UE based on the WLAN cell access status information included in the received WLAN access authentication message.

Further, the eNB includes transmitting tunnel configuration information for establishing a tunnel between the eNB and the UE through WLAN radio resources to the UE through higher layer signaling in operation S530. When the WLAN cell access authentication of the UE is completed, the eNB may use the WLAN radio resource transport tunnel to establish the required parameters. The parameter may be transmitted by being included in the tunnel configuration information and may be transmitted by an RRC connection reconfiguration message.

The higher layer signaling including the tunnel configuration information may further include tunnel bearer configuration information for configuring a radio bearer using the tunnel. The tunnel bearer configuration information may include DRB identification information related to a DRB configured to transmit/receive data using a tunnel. The eNB may configure a radio bearer specified based on the DRB identification information among the radio bearers as a radio bearer using the tunnel.

Fig. 6 is a diagram illustrating an operation of an eNB (including tunnel setup) according to another embodiment of the present invention.

Referring to fig. 6, the eNB further includes an operation of establishing an IPsec tunnel through WLAN radio resources based on the tunnel configuration information and transmitting/receiving data to/from the UE using the IPsec tunnel in operation S640. Operations S510 to S530 are performed in the same manner as described in fig. 5, and thus, a detailed description thereof will be omitted.

The eNB may establish an IPsec tunnel with the UE based on the tunnel configuration information. Further, the eNB may similarly configure the radio bearers using the IPsec tunnel based on the tunnel bearer configuration information. The eNB may transmit/receive data of a tunnel bearer to/from the UE using an IPsec tunnel (which is set using WLAN radio resources). To this end, a tunnel bearer may be associated with the tunnel entity, and the tunnel entity adds an IPsec header to data of the upper layer and transmits it to the lower layer, and removes the IPsec header from data received from the lower layer and transmits it to the upper layer. The tunnel entity of the eNB may be configured to peer with the tunnel entity of the UE.

As described above, the present embodiment can reduce the delay associated with WLAN access authentication and tunnel establishment and data transmission interruption caused by a small coverage, and can provide LTE-WLAN aggregation based on an IPsec tunnel capable of reusing an existing WLAN AP.

A UE and an eNB that can perform all or some of the operations in the present embodiment of the present invention that have been described in the above description will be described with reference to the accompanying drawings.

Fig. 7 is a block diagram illustrating a configuration of a UE according to another embodiment of the present invention.

Referring to fig. 7, a UE700 that transmits/receives data includes: a receiving unit 730 that receives WLAN cell configuration information for transmitting and receiving data using WLAN radio resources from an eNB; a controller 710 performing a WLAN association operation based on the WLAN cell configuration information; a transmitting unit 720, which transmits a WLAN access confirmation message to the eNB.

After transmitting the WLAN access confirmation message, the receiving unit 730 also receives tunnel configuration information for the UE to establish a tunnel with the eNB through the WLAN radio resource from the eNB through higher layer signaling.

The receiving unit 730 may receive the tunnel bearer configuration information through higher layer signaling, and the tunnel bearer configuration information may include information for configuring a radio bearer using the tunnel. For example, the tunnel bearer configuration information may include DRB identification information related to a DRB configured to use the tunnel.

The controller 710 may establish an IPsec tunnel with the eNB based on the tunnel configuration information and may configure a tunnel bearer using the tunnel bearer configuration information.

Further, the controller 710 controls the overall operation of the UE700 in conjunction with the detailed control procedure and data transmission method of the tunnel-based LTE-WLAN aggregation technology using WLAN radio resources, which are required to implement the above-described embodiments.

Further, the transmitting unit 720 and the receiving unit 730 may be used to transmit/receive signals, messages or data required to implement the above-described present invention to/from the eNB.

Referring to fig. 8, an eNB 800 transmitting/receiving data may include: a transmitting unit 820 that transmits WLAN cell configuration information for transmitting and receiving data using WLAN radio resources to a UE; a receiving unit 830, which receives a WLAN access confirmation message from the UE.

After receiving the WLAN access confirmation message, the transmitting unit 820 may transmit tunnel configuration information for establishing a tunnel between the eNB and the UE through WLAN radio resources to the UE through higher layer signaling. Further, the transmitting unit 820 may transmit tunnel bearer configuration information for configuring a radio bearer using a tunnel to the UE. The tunnel bearer configuration information may be transmitted together with the tunnel configuration information.

The controller 810 may set an IPsec tunnel through the WLAN radio resource based on the tunnel configuration information and may configure a tunnel bearer.

Further, the controller 810 controls the overall operation of the UE700 in association with detailed control procedures and data transmission methods of the tunnel-based LTE-WLAN aggregation technology using WLAN radio resources, which are required to implement the above-described embodiments.

In addition, the receiving unit 830 may receive uplink control information, uplink data, and messages from the UE through corresponding channels. The transmitting unit 820 may transmit downlink control information, downlink data and messages to the UE through corresponding channels.

The contents related to the standards and the standard documents mentioned in the above embodiments have been omitted for the sake of brief description of the present specification, but may be made a part of the present specification. Accordingly, when contents and documents related to the standards are added to the present specification or specified in the claims, they should be considered as a part of the present invention.

Although the preferred embodiments of the present invention have been described for illustrative purposes, those skilled in the art will appreciate that various modifications, additions and substitutions are possible, without departing from the scope and spirit of the invention as disclosed in the accompanying claims. Accordingly, the exemplary aspects of the invention are not described for limiting purposes. The scope of the present invention should be construed as being based on the appended claims in a manner such that all technical ideas included within the scope equivalent to the claims are included in the present invention.

Claims

1. A method for a User Equipment (UE) to transmit and receive data, the method comprising:

receiving, from an evolved node B (eNB), Wireless Local Area Network (WLAN) cell configuration information for transmitting and receiving data using WLAN radio resources, wherein the WLAN cell configuration information includes WLAN mobility set information;

performing WLAN association based on the WLAN cell configuration information;

transmitting a WLAN access confirmation message to the eNB; and

receiving tunnel configuration information for the UE and the eNB to establish a tunnel through the WLAN radio resource from the eNB through higher layer signaling,

wherein the tunnel configuration information includes tunnel entity configuration information including Internet key exchange establishment information for configuring a tunnel entity,

the tunnel entity is configured in a layer higher than the PDCP layer, adds an Internet protocol Security (IPsec) header to data received from the IP layer, and removes the IPsec header from data received through an Ipsec tunnel,

the tunnel entity is configured to peer with a peer tunnel entity configured in the eNB and to encapsulate and decapsulate data sent and received over the Ipsec tunnel,

the higher layer signaling further includes tunnel bearer configuration information including Data Radio Bearer (DRB) identification information configured to transmit and receive data using the tunnel,

the UE associating a radio bearer specified through the DRB identification information with the tunnel entity, thereby configuring a radio bearer using the Ipsec tunnel,

the UE transmits data obtained by adding the IPsec header to an IP packet received from the IP layer using a radio bearer designated by the DRB identification information,

the tunnel entity is configured in a layer higher than the PDCP layer separately from the PDCP layer, and is associated with a radio bearer using an Ipsec tunnel that is configured to be distinguished from an E-UTRAN bearer associated with the PDCP layer.

2. The method of claim 1, further comprising:

setting up an Internet protocol security (IPsec) tunnel over WLAN radio resources based on the tunnel bearer configuration information; and

and transmitting and/or receiving data to/from the eNB by using the IPsec tunnel.

3. A method for an evolved node b (enb) to transmit and receive data, the method comprising:

transmitting Wireless Local Area Network (WLAN) cell configuration information to a User Equipment (UE) for transmitting and receiving data using WLAN radio resources, wherein the WLAN cell configuration information includes WLAN mobility set information;

receiving a WLAN access confirmation message from the UE; and

transmitting tunnel configuration information for the eNB and the UE to establish a tunnel through the WLAN radio resource to the UE through higher layer signaling,

the tunnel entity is configured to peer with a tunnel entity configured in the UE and encapsulate and decapsulate data sent and received over the Ipsec tunnel,

4. The method of claim 3, further comprising:

and transmitting and/or receiving data to/from the UE through the IPsec tunnel.

5. A User Equipment (UE) that transmits and receives data, the UE comprising:

a receiving unit which receives, from an evolved node B (eNB), Wireless Local Area Network (WLAN) cell configuration information for transmitting and receiving data using WLAN radio resources, wherein the WLAN cell configuration information includes WLAN mobility set information;

a controller that performs WLAN association based on the WLAN cell configuration information;

a transmitting unit which transmits a WLAN access confirm message to the eNB,

wherein the receiving unit further receives tunnel configuration information for the UE and the eNB to establish a tunnel through the WLAN radio resource from the eNB through higher layer signaling after transmitting the WLAN access confirmation message,

the controller associates a radio bearer specified through the DRB identification information with the tunnel entity, thereby configuring a radio bearer using the Ipsec tunnel,

the transmission unit transmits data obtained by adding the IPsec header to an IP packet received from the IP layer using a radio bearer specified by the DRB identification information,

6. The UE of claim 5, wherein the controller establishes an Internet protocol Security (IPsec) tunnel over WLAN radio resources based on the tunnel configuration information; and is

The transmitting unit transmits data to an eNB by using the IPsec tunnel, and the receiving unit receives data from the eNB by using the IPsec tunnel.