KR20120131045A - Method and local gateway for providing mobility between local networks - Google Patents

Abstract

PURPOSE: A method for providing mobility between the local networks and local gateway thereof are provided to reduce traffic concentration in a specific apparatus and traffic transmission paths. CONSTITUTION: A source L-GW(local-gateway) of a source local network data received from a packet data network to UE(user equipment) connected to the source L-GW through a source HeNB(home enodeb)(S300). The source HeNB of an UE cell is converted into a target HeNB connected with the target L-GW of a neighbor target local network(S302). The source L-GW transmits the data received from the packet data network to the UE through tunneling of the data in the target HeNB by using the interface and the target L-GW(S304,S306). [Reference numerals] (AA) Start; (BB) End; (S300) Data transmission step before moving a terminal; (S302) Cell conversion step according to moving a terminal; (S304) Signaling step; (S306) Data forwarding step through tunneling

Description

METHOD AND LOCAL GATEWAY FOR PROVIDING MOBILITY BETWEEN LOCAL NETWORKS}

The present invention relates to a technology for providing inter-network mobility of a terminal.

When a terminal moves between local networks connected to a core network, there has been a problem in that it does not provide mobility between local networks, a long traffic transmission path, or traffic is concentrated on a specific network device.

In this context, it is an object of the present invention to efficiently provide mobility between local networks.

In addition, another object of the present invention is to reduce the traffic transmission path and reduce traffic concentration to a specific device while providing mobility between local networks.

In order to achieve the above object, in one aspect, the present invention provides a method for providing mobility between local networks, the source local base station of the source local network of the source local network is connected to the source local gateway to the data received from the packet data network Transmitting to the terminal through; Changing the cell of the terminal from a cell of the source local base station to a cell of a target local base station connected to a target local gateway of a target local network adjacent to the source local network; And tunneling, by the source local gateway, the data received from the packet data network to the target local base station through an interface with the target local gateway and forwarding the data to the terminal.

In another aspect, the present invention provides a method for providing mobility between local networks, the source local gateway of the source local network transmitting the data received from the packet data network to the terminal through the source local base station connected to the source local gateway; Changing the cell of the terminal from a cell of the source local base station to a cell of a target local base station connected to a target local gateway of a target local network adjacent to the source local network; The source local gateway tunneling data received from the packet data network to the target local gateway through an interface with the target local gateway; And providing, by the target local gateway, tunneling data tunneled from the source local gateway to the target local base station and forwarding the data to the terminal.

As described above, the present invention has the effect of efficiently providing mobility between local networks.

In addition, according to the present invention, while providing mobility between local networks, it reduces the traffic transmission path and has the effect of reducing the traffic concentration to a specific device.

1 is a diagram schematically illustrating a system architecture applied to an embodiment of the present invention.
2 is a diagram illustrating an interface between devices in a system architecture applied to an embodiment of the present invention.
3 is a flowchart of a method for providing mobility between local networks according to an embodiment of the present invention.
4 is a detailed flowchart of a method for providing mobility between local networks according to an embodiment of the present invention.
5 is a diagram illustrating a data forwarding flow according to a method for providing mobility between local networks according to an embodiment of the present invention.
6 is a flowchart of a method for providing mobility between local networks according to another embodiment of the present invention.
7 is a diagram illustrating a signaling procedure for providing mobility between local networks according to another embodiment of the present invention.
8 is a diagram illustrating a data forwarding flow according to a method for providing mobility between local networks according to another embodiment of the present invention.
9 is a block diagram of a target local gateway providing mobility between local networks according to an embodiment of the present invention.
10 is a block diagram of a source local gateway providing mobility between local networks according to an embodiment of the present invention.

Hereinafter, some embodiments of the present invention will be described in detail with reference to exemplary drawings. In adding reference numerals to the components of each drawing, it should be noted that the same reference numerals are assigned to the same components as much as possible even though they are shown in different drawings. In the following description of the present invention, a detailed description of known functions and configurations incorporated herein will be omitted when it may make the subject matter of the present invention rather unclear.

In addition, in describing the component of this invention, terms, such as 1st, 2nd, A, B, (a), (b), can be used. These terms are intended to distinguish the constituent elements from other constituent elements, and the terms do not limit the nature, order or order of the constituent elements. When a component is described as being "connected", "coupled", or "connected" to another component, the component may be directly connected to or connected to the other component, It should be understood that an element may be "connected," "coupled," or "connected."

1 is a diagram schematically illustrating a system architecture applied to an embodiment of the present invention.

As shown in FIG. 1, a system architecture applied to an embodiment of the present invention includes a core network 13 and a plurality of local networks connected to the core network 13 to support mobility between the local networks of the terminal 100. It is structured to include the network 115 hierarchically.

Terminal 100 in the present specification is a comprehensive concept that means a user terminal in a wireless communication, WCDMA and UE in GSM, LTE-A, HSPA, etc., as well as MS (Mobile Station), UT (User Terminal) in GSM ), SS (Subscriber Station), wireless device (wireless device), etc. should be interpreted as including the concept.

As a system architecture to which embodiments are applied in the present specification, a macro network 13 and two local networks 11 and 12 connected thereto, as defined or defined in 3GPP, which enact technical specifications of a mobile communication system, will be described. However, the present invention is not limited thereto.

The macro network 13 is a mobility management entity (MME: Mobility Management Entity, hereinafter referred to as “MME”, 133) that is responsible for processing a base station 134 and a control signal of an evolved UTRAN, and a serving gateway. (S-GW: Serving-Gateway, hereinafter referred to as "S-GW", 132), Core including packet data network gateway (P-GW: `` P-GW '', 131) As a network (Core Network), it is also referred to as "Evolved Packet Core" (EPC).

The base station 134 included in the macro network 13 refers to a fixed station in which a cell having a constant radius is used as a service area and generally communicates with the terminal 100, and is a node-B according to a system type. -B), an evolved Node-B (eNB), a Base Transceiver System (BTS), an Access Point, an Access Point, or a Relay Node.

The uplink traffic of the terminal 100 in the macro network 13 goes to the P-GW 131 via the S-GW 132 through the base station 134, the downlink traffic to the P-GW 131 Through the S-GW 132 is transmitted to the terminal 100 through the base station 134 through. In this case, the MME 133 may be in charge of processing a control signal and managing mobility when providing mobility between networks. In this case, the MME 133 may consider an operator policy, quality of service (QoS), subscriber information, etc. in addition to the control signals received from the terminal 100 and the S-GW 132.

Referring to FIG. 2, which shows the system architecture of FIG. 1 in more detail and shows an interface between devices, a control plane between an access network and a core network 13 between a terminal 100 and a base station 134. Plane and User Plane are exchanged with different interfaces.

That is, the control plane between the base station 134 and the MME 133 indicated by the eNB uses the S1-MME interface, and the user plane between the base station 134 and the S-GW 132 indicated by the eNB refers to the S1-U interface. Can be used. Meanwhile, the base station 134 indicated by the eNB may use the X2 interface, the S-GW 132 and the P-GW 131 may use the S5 interface, and the P-GW 131 and the Internet may use the SGi interface. .

Meanwhile, as illustrated in FIG. 2, the macro network 13 may include a separate gateway, for example, a security gateway 250 (SeGW).

The local networks 11 and 12 are hierarchically interworking with the macro network 13 described above. For example, the local networks 11 and 12 refer to networks of a smaller size than the macro network 130 such as a home network or an office network. . The local networks 11 and 12 may include local gateways 111 and 121 connected with the serving gateway 132 of the macro network 130 and local base stations 112 and 122 connected with the local gateways 111 and 121. It has a structure to include.

For example, the above-described local base stations 112 and 122 may be installed indoors as base stations of a universal mobile telecommunication system (UMTS) network and have a cell coverage of a home node B (HNB) corresponding to a femtocell, or an evolved packet system (EPS). It is installed indoors as a base station of the network and the cell coverage scale includes, but is not limited to, Home eNodeB (HeNB) corresponding to a femtocell. These local base stations 112 and 122 may be identical to the base station 134 of the macro network 13 except for being included in the local networks 11 and 12.

The local gateways 111 and 121 are located between the local base stations 112 and 122 and the internet network, which is a packet data network, and create a bearer between the local base stations 112 and 122 and the local network. Create a bearer between the 112 and 122 and the local gateways 111 and 121, and enable data transmission through the created bearer.

Meanwhile, the local gateways 111 and 121 enable Selected IP Traffic Offload (SIPTO) or Local IP Access (LIPA) through the local base stations 112 and 122. The SIPTO is a mobile communication operator's network (eg, 3GPP) when the terminal 100 transmits specific traffic through the base station 134 of the macro network 13 or the local base stations 121 and 122 of the local networks 11 and 12. , 3GPP2), means a technique for bypassing the Internet network, and LIPA connects the local base stations 112 and 122 with the local networks 11 and 12, and in the cell of the base station 134 of the macro network 13 The terminal 100 may be a technology for enabling the terminal 100 to access the local networks 11 and 12 through the local base stations 112 and 122.

Referring to FIG. 2, which illustrates the system architecture of FIG. 1 in more detail and shows the interface between devices, the local base stations 112, 122, denoted by HeNB, are identical to the S1-MME and the base stations 134 of the macro network 13; S1-U, X2 interface is available. Meanwhile, the local base stations 112 and 122 denoted by HeNB and the local gateways 111 and 121 denoted by L-GW may use the Sxx interface. The local gateways 111 and 121 and the Internet network indicated by L-GW may use the SGi interface.

Meanwhile, the present invention provides mobility between local networks of the terminal 100. Referring to FIG. 1, the terminal 100 before the movement is connected to a source local base station 112 (Source HeNB) of the source local network 11. The downlink traffic is received through the source local gateway 111 (Source L-GW) and the source local base station 112 (110 Traffic Flow).

If the terminal 100 moves from the source local network 11 to the target local network 12, the terminal 100 then provides two types of traffic according to the provision of mobility between local networks according to an embodiment of the present invention. Even after moving along the flow 130, the downlink traffic received to the source local gateway 111 can be seamlessly received.

The first traffic flow 130, the data received by the source local gateway 111 in the Internet network, through the S-GW 132 through the S5 interface and again through the target local gateway 121 through the S5 interface target The flow is forwarded to the terminal 100 through the local base station 122.

Through the first traffic flow 130, downlink traffic received by the source local gateway 111 may be forwarded to the terminal 100 without interruption, thereby providing mobility between local networks. However, since data bypasses the S-GW 132, there are disadvantages in that the length of the data transmission path is long and traffic is concentrated in the S-GW 132.

The second traffic flow 120, in order to overcome the above-mentioned disadvantages, the data received by the source local gateway 111 in the Internet network is not transmitted to the S-GW 132 via the S5 interface, "local gateway It is a flow transmitted to the target local gateway 121 through the "Syy interface, which is a newly defined interface, and forwarded to the terminal 100 through the target local base station 122.

Through this first traffic flow 130, the downlink traffic received to the source local gateway 111 can be forwarded to the terminal 100 without interruption, and since the data does not bypass the S-GW 132, the data The drawback of lengthening the transmission path length and the drawback of traffic concentration in the S-GW 132 can be solved.

The terms "Source" and "Target" mentioned above are used to distinguish the device before and after the movement of the terminal 100 for convenience of description.

By providing mobility between local networks in the present specification, service continuity may be provided even when the terminal 100 moves between local networks.

In the present specification, the terminal 100, the base station 134 of the macro network 13, and the local base stations 112 and 122 of the local networks 11 and 12 may be used to implement the technology or technical idea described herein. It is used in a comprehensive sense as a subject to transmit and receive a branch and is not limited by the term or word specifically referred to.

There is no limitation on the multiple access scheme applied to the wireless communication system. Various multiple access techniques such as Code Division Multiple Access (CDMA), Time Division Multiple Access (TDMA), Frequency Division Multiple Access (FDMA), Orthogonal Frequency Division Multiple Access (OFDMA), OFDM-FDMA, OFDM-TDMA, OFDM-CDMA Can be used.

Uplink (downlink) transmission and downlink (downlink, or downlink) transmission may use a time division duplex (TDD) scheme, which is transmitted using different times, or transmit using different frequencies. A frequency division duplex (FDD) scheme may be used.

One embodiment of the present invention is resource allocation in the field of asynchronous wireless communication evolving into Long Term Evolution (LTE) and LTE-advancedA through GSM, WCDMA, HSPA, and synchronous wireless communication evolving into CDMA, CDMA-2000 and UMB. Can be applied to The present invention should not be construed as being limited or limited to a specific wireless communication field, but should be construed as including all technical fields to which the spirit of the present invention can be applied.

A system to which an embodiment of the present invention is applied may support uplink and / or downlink hybrid automatic repeat request (HARQ), and may use channel quality indicator (CQI) for link adaptation. In addition, multiple access schemes for downlink and uplink transmission may be different. For example, the downlink uses Orthogonal Frequency Division Multiple Access (OFDMA), and the uplink uses Single Carrier-Frequency Division Multiple Access (SC-FDMA). ) Is the same as that available.

The layers of the radio interface protocol between the terminal 100 and the networks 11, 12, and 13 may include lower three layers of the Open System Interconnection (OSI) model, which is well known in a communication system. Based on the first layer (L1), the second layer (L2), can be divided into the third layer (L3), the physical layer belonging to the first layer information transfer service (information transfer) using a physical channel (physical channel) service).

A method of providing mobility between local networks according to the above-described embodiment of the present invention briefly described above will be described in more detail with reference to FIGS. 3 to 8.

Hereinafter, the source local gateway 111 is called "Source L-GW", the source local base station 112 is called "Source HeNB", and the target local gateway 121 is called "Target L-GW". The local base station 122 is called "Target HeNB", the mobility management device 133 is called "MME", the terminal 100 is called "UE". This is merely an example for convenience of description and should not be limited thereto.

The method for providing mobility between local networks according to an embodiment of the present invention with reference to FIGS. 3 to 8 will first be described several matters before the description.

In the method for providing mobility between local networks according to an embodiment of the present invention, an Syy interface, which is an interface between L-GWs, is further defined in the L-GW architecture shown in the current LIMONET standard (3GPP TR23.859).

Initial operation of the present invention is the same as the existing LIPA operation. That is, the UE 100 receives an IP address corresponding to an IP address area managed by the P-GW 131 selected by the APN (Access Point Name) and authenticated by the core network 13 during initial access. . At this time, the UE 100 accesses the HeNB and is assigned a local IP address from the corresponding L-GW during LIPA operation, and the corresponding IP traffic is transmitted directly to the PDN (Internet network) through the corresponding L-GW rather than being transmitted to the core network. Traffic offloading effect is obtained.

As such, the IP address used by the UE 100 is valid within the domain of the P-GW 131 or the domain of the corresponding L-GW, and the IP address used by different P-GWs or different L-GWs may be used. There is a possibility of duplication. Therefore, when leaving the domain of the P-GW 131 or the domain of the L-GW, it should be distinguished using the core network address of the P-GW or the L-GW. In other words, LIPA uses the local IP address inside the L-GW and uses the core network address of the L-GW when it is out of the L-GW.

Since the present invention deals with the L-GW interworking through the Syy interface, it is necessary to know the core network address between the L-GWs and know which L-GWs come from when the UE 100 enters from another L-GW. In other words, when the UE 100 enters the target L-GW 121, it should know the source L-GW 111. That is, since the P-GW 131 and the L-GW can distinguish the P-GW 131 through the APN, the P-GW 131 may form a tunnel with the corresponding S-GW 132, but the current standard between the L-GW. Indistinguishable from each other, a new definition is required.

Of course, the mobility management of the user terminal, that is, the UE 100 can be known through the MME 133, but since the LIPA traffic is not transmitted through the core network 13, the cost of signaling with the MME 133 only for the LIPA traffic. There is also a need for a method that does not use the MME 133 to eliminate the cost and to enable rapid mobility management.

Accordingly, in the present invention, the home L-GW of the UE 100, which is a user terminal that defines a Syy interface, which is an interface between L-GWs, and enters through information exchange between L-GWs on the Syy interface, which is an interface between L-GWs. (Ie, Source L-GW 111) is of utmost importance.

Hereinafter, a method of providing mobility between local networks using mobility management through the MME 133 will be described with reference to FIGS. 3 to 5.

3 is a flowchart of a method for providing mobility between local networks according to an embodiment of the present invention.

Referring to FIG. 3, in the method for providing mobility between local networks according to an embodiment of the present invention, the source L-GW 111 of the source local network 11 is received from a packet data network (eg, an internet network). Transmitting the data to the UE 100 through the Source HeNB 112 connected to the Source L-GW 111 (S300), and the target local adjacent to the source local network 11 in the cell of the Source HeNB 112. In step S302, in which the cell of the UE 100 is changed into a cell of the target HeNB 122 connected to the target L-GW 121 of the network 12, the source L-GW 111 may be a packet data network (eg, Tunneling the data received from the Internet network, etc.) to the target HeNB 122 through an interface (eg, Syy interface) with the target L-GW 121 (S306), and the like. Include.

On the other hand, as shown in Figure 3, the method for providing mobility between local networks according to an embodiment of the present invention, between the step S302 and S306 described above, that is, before the step S306, Target HeNB 122 In order to inform the fact that the cell of the UE 100 has changed, a path switch request message (Path Switch Request) is transmitted to the MME 133, and the MME 133 is a tunnel for downlink traffic forwarding. A setup request message (eg Modify Bearer Request) is sent to the S-GW 132, and the S-GW 132 sends a tunnel setup change request message (eg, Modify Bearer Request) for downlink traffic forwarding. Send to the GW 111, the Source L-GW 111 sends a tunnel setup change response message (eg, Modify Bearer Response) to the S-GW 132, and the S-GW 132 tunnel setup response message. (Eg, Modify Bearer Response) to the MME 133, and the MME 133 sends a path switch request response message (Path Switch Respon). se) may be transmitted to the target HeNB 122, and the target HeNB 122 may further include a signaling step S304 informing the source HeNB 112 of the successful handover.

As described above, in the method for providing mobility between local networks according to an embodiment of the present invention, the mobility management function through the MME 133 is used.

The target HeNB 122 transmits the terminal information to the S-GW 132 through the S1 interface, and the S-GW 132 updates the location information by notifying the MME 133 of the location of the UE 100 through the S11 interface. do. Therefore, the source L-GW 111 that recognizes the movement information of the UE 100 through the Sxx interface transmits traffic through the tunneling with the target HeNB 122. This requires a mutual agreement between the L-GWs. Therefore, whether to allow access through the Syy interface, information exchange and policy setting of HeNB, etc. owned by the user, can be made.

In this case, the mobility management procedure of the S11 interface level is required for the Sxx interface in order to guarantee service continuity through fast handover when moving between HeNBs.

A method of providing mobility between local networks according to an embodiment of the present invention described above will be described with reference to the detailed flowchart of FIG. 4.

Referring to FIG. 4, the UE 100 is connected to the Source HeNB 112 of the source local network 11, so that the UE 100 transmits downlink data through the Source HeNB 112 and the Source L-GW 111. And uplink data (Downlink / Uplink User Plane Data) is transmitted and received (S400).

On the other hand, through the L-GW interface (Syy interface), the target L-GW 121 to which the source L-GW 111 and the UE 100 will move is allowed to connect, and H (e) that is available to them. Information exchange on the NB, Packet Data Network (PDN), Local H (e) NB Network-Identifier (LHN-ID), and the like is exchanged (S402).

When the UE 100 moves from the source HeNB 112 of the source local network 11 to the cell area of the target HeNB 122 of the target local network 12, the source HeNB 112 and the target HeNB 122 are moved. A handover preparation step is performed while sending and receiving a handover request and response (S404).

Thereafter, the source HeNB 112 transmits a handover command to the UE 100, and the UE 100 executes handover such as transmitting a handover complete message (Handover Complete) to the target HeNB 122. A handover execution step is performed (S406). At this time, the source HeNB 112 forwards the data received before the handover execution step to the target HeNB 122 (S408), and the target HeNB 122 transmits the UE if the forwarded data is downlink data. Transmit to 100 (S410).

The target HeNB 122 where the UE 100 moves and currently located transmits uplink data transmitted by the UE 100 through the Source L-GW 111.

In order to provide mobility between local networks according to an embodiment of the present invention, the following signaling procedure is performed.

The target HeNB 122 transmits a path switch request message to the MME 133 to inform the fact that the cell of the UE 100 has changed (S414).

The MME 133 transmits a tunnel establishment request message (for example, Modify Bearer Request) for downlink traffic forwarding to the S-GW 132 (S416).

The S-GW 132 transmits a tunnel configuration change request message (eg, Modify Bearer Request) for the downlink traffic forwarding to the Source L-GW 111 (S418).

The source L-GW 111 transmits a tunnel configuration change response message (eg, Modify Bearer Response) to the S-GW 132 (S420).

The S-GW 132 transmits a tunnel establishment response message (eg, Modify Bearer Response) to the MME 133 (S422).

The MME 133 transmits a path switch request response message (Path Switch Response) to the target HeNB 122 (S428).

The target HeNB 122 transmits a resource release message (Release Resource) to the source HeNB 112 to inform that the handover is successful (S430).

After step S420 described above, data forwarding may be performed. After the source L-GW 111 forms a tunnel to the target HeNB 122, the source L-GW 111 encapsulates the received downlink data to tunnel to the target HeNB 122. Forwarding (S424), the target HeNB 122 decapsulates the forwarded data and delivers it to the UE (S426).

Thereafter, the tracking area update procedure may be performed (S432).

FIG. 5 illustrates a downlink data forwarding flow according to a method for providing mobility between local networks according to an embodiment of the present invention described above.

Referring to FIG. 5, while in the source local network 11, the UE 100 receives downlink data from the Source L-GW 111 and the Source HeNB 112 (flow 110).

Thereafter, the UE 100 moves from the source local network 11 to the adjacent target local network 12, and another UE that has been transmitting data to the UE 100 knows the UE 100's movement without knowing it. The data is continuously transmitted to the UE 100 using the existing address information (for example, the IP address allocated from the source local network 11).

According to a method for providing mobility between local networks according to an embodiment of the present invention, after the movement between the local networks of the UE 100, a tunnel is formed between the Source L-GW 111 and the Target HeNB 122, and the Source L- The GW 111 forwards data continuously received after the UE 100 moves through tunneling to the target HeNB 122 where the UE 100 is currently located (flow 120).

At this time, when the source L-GW 111 forwards data through tunneling to the target HeNB 122 where the UE 100 is currently located, the source L-GW 111 does not bypass the S-GW 132 through the S5 interface, and thus source L-GW 111. Forward to the target L-GW 121 through an interface between the GW 111 and the target L-GW 121 (Syy interface).

Hereinafter, a method of providing mobility between local networks that may reduce signaling burden with the MME 133 will be described with reference to FIGS. 6 to 8.

6 is a flowchart of a method for providing mobility between local networks according to another embodiment of the present invention.

Referring to FIG. 6, in a method of providing mobility between local networks according to another embodiment of the present invention, the source L-GW 111 of the source local network 11 is received from a packet data network (eg, an internet network). Transmitting the data to the UE 100 through the Source HeNB 112 connected to the Source L-GW 111 (S600), and the target of the target local network adjacent to the source local network in the cell of the Source HeNB 112. In step S602, a cell of the UE 100 is changed into a cell of the target HeNB 122 connected to the L-GW 121, and the source L-GW 111 is received from a packet data network (eg, an internet network). Tunneling (first tunneling) the data to the target L-GW 121 through an interface (Syy interface) with the target L-GW 121 (S606), and the target L-GW 121 is the source L-GW And tunneling (second tunneling) the data tunneled from the 111 to the target HeNB 122 and forwarding the data to the UE 100 (S608).

Meanwhile, as shown in FIG. 6, in the method for providing mobility between local networks according to another exemplary embodiment of the present invention, between step S602 and step S606, that is, before step S606, the target HeNB 122 may transmit the UE 100. ) Transmits a path switch request message (Path Switch Request) to the target L-GW 121 to inform the fact that the cell of the cell is changed, and the target L-GW 121 transmits a source L-GW (111) for downlink traffic forwarding. Send a session establishment request message (Create Session Request), the source L-GW 111 sends a session establishment response message (Create Session Response) to the target L-GW 121, Target L-GW (121) ) Transmits a path switch response message (Path Switch Response) to the target HeNB (122), the target HeNB (122) resource release message (Release Resource) to the source HeNB (112) to which the UE (100) is connected before moving The method may further include a signaling step S604 informing that the handover has been successful by transmitting. .

As described above, the method for providing mobility between local networks according to another embodiment of the present invention is a case in which signaling with the MME 133 is not necessary through L-GW mobility management through Syy. In this case, the L-GWs exchange information with each other through the L-GW @ CN address, which is a core network address. The target L-GW 121 determines whether the user terminal receiving the Internet service through the LIPA, the UE 100 is managed by its L-GW upon entry, and if the terminal is not managed by the target L-GW It is important to find the Source L-GW 111 of the terminal.

Accordingly, the Syy interface, which is an interface between L-GWs, exchanges information such as H (e) NB information and PDN information connected to itself between L-GWs adjacent to each other, and source L connected to the source HeNB 112 during handover. Establishing a quick connection with the GW 111 ensures session continuity through LIPA of the UE 100.

In this case, the target L-GW 121 plays the same role as the S-GW 132 in the core network 13, and the source L-GW 111 plays a role with the P-GW 131 in the core network 13. It can be seen that it performs the same function.

In addition, through the exchange of information between the L-GW through the L-GW interface (Syy interface), if the connected UE 100 wants a PDN access service that cannot be provided by the L-GW (for example, Internet service). When a user terminal requests VoIP service to an L-GW connected to a PDN that provides only a service), a corresponding L-GW capable of providing a PDN connection service that cannot be provided may also be provided to provide a service. Such functionality may also be provided in a system for providing mobility between local networks in accordance with one embodiment of the present invention.

7 is a detailed flowchart of a method for providing mobility between local networks according to another embodiment of the present invention.

Referring to FIG. 7, referring to FIG. 4, the UE 100 is connected to the Source HeNB 112 of the source local network 11, so that the UE 100 connects to the Source HeNB 112 and the Source L-GW 111. Downlink data and uplink data (Downlink / Uplink User Plane Data) are transmitted and received (S702).

On the other hand, through the L-GW interface (Syy interface), the target L-GW 121 to which the source L-GW 111 and the UE 100 will move is allowed to connect, and H (e) that is available to them. Information exchange on the NB, the Packet Data Network (PDN), the Local H (e) NB Network-Identifier (LHN-ID), and the like is exchanged (S700).

When the UE 100 moves from the source HeNB 112 of the source local network 11 to the cell area of the target HeNB 122 of the target local network 12, the source HeNB 112 and the target HeNB 122 are moved. A handover preparation step is performed while sending and receiving a handover request and response (S704).

Thereafter, the source HeNB 112 transmits a handover command to the UE 100, and the UE 100 executes handover such as transmitting a handover complete message (Handover Complete) to the target HeNB 122. A (Handover Execution) step is performed (S706). At this time, the source HeNB 112 forwards the data received before the handover execution step to the target HeNB 122 (S708), and the target HeNB 122 transmits the forwarded data to the UE 100. (S712).

Meanwhile, in order to provide mobility between local networks according to another embodiment of the present invention, the following signaling procedure is performed.

The target HeNB 122 transmits a path switch request message to the target L-GW 121 for notifying that the cell of the UE 100 has changed (S710).

The target L-GW 121 transmits a session establishment request message (Create Session Request) to the source L-GW 111 for downlink traffic forwarding (S714).

The source L-GW 111 transmits a session establishment response message (Create Session Response) to the target L-GW 121 (S716).

The target L-GW 121 transmits a path switch response message to the target HeNB 122 (S718).

The target HeNB 122 notifies that the handover is successful by transmitting a resource release message (Release Resource) to the source HeNB 112 to which the UE 100 is connected before the movement (S732).

After the above-described step S718, data forwarding may be performed. After the tunnel is formed from the source L-GW 111 to the target L-GW 121 and another tunnel is formed from the target L-GW 121 to the target HeNB 122, the source L-GW 111 is received. Encapsulation of the downlink data is tunneled to forward to the target L-GW 121 (S720), and the target L-GW 121 tunnels the forwarded data back to the target HeNB 122 and forwards it. In operation S722, the target HeNB 122 decapsulates the forwarded data and delivers the decapsulated data to the UE 100 (S424).

If the target HeNB 122 receives uplink data to the UE 100 (S726), the target HeNB 122 transmits the data through the target L-GW 121 and the source L-GW 111 (S728 and S730).

8 is a diagram illustrating a data forwarding flow according to the method for providing mobility between local networks according to another embodiment of the present invention described above.

Referring to FIG. 8, while in the source local network 11, the UE 100 receives downlink data from the Source L-GW 111 and the Source HeNB 112 (flow 110).

Thereafter, the UE 100 moves from the source local network 11 to the adjacent target local network 12, and another UE that has been transmitting data to the UE 100 knows the UE 100's movement without knowing it. The data is continuously transmitted to the UE 100 using the existing address information (for example, the IP address allocated from the source local network 11).

According to the method for providing mobility between local networks according to an embodiment of the present invention, after the movement between the local networks of the UE 100, a tunnel is formed between the Source L-GW 111 and the Target L-GW 121 and the Target L is selected. A tunnel is formed between the GW 121 and the target HeNB 122. Accordingly, the source L-GW 111 forwards data continuously received even after the UE 100 moves to the target L-GW 121 where the UE 100 is currently located through tunneling, and the target L-GW. 121 forwards the forwarded data back to the target HeNB 122 through tunneling (flow 120).

At this time, the source L-GW 111 does not bypass the S-GW 132 through the S5 interface for downlink data forwarding to the target HeNB 122 where the UE 100 is currently located. Forward to the target L-GW 121 through the interface between the 111 and the target L-GW 121 (Syy interface).

The local gateway (L-GW) providing mobility between local networks according to the above-described embodiment of the present invention is the target local gateway (Target L-GW) 121 and the source local gateway (Source L-GW) 111. 9 and 10 will briefly be described with respect to each case of operation.

9 is a block diagram of a target local gateway (Target L-GW) 121 that provides mobility between local networks according to an embodiment of the present invention.

Referring to FIG. 9, the target local gateway 121 providing mobility between local networks according to an embodiment of the present invention may be connected to an adjacent local network (source local network 11) through an inter-gateway interface (Syy interface). Information exchange unit 910 for exchanging information with a local gateway (source local gateway 111) of the home of the terminal 100 entering its local network (target local network 12) through the exchanged information And a home local gateway recognition unit 920 of the mobile terminal that recognizes the local gateway. Here, the home local gateway of the terminal 100 is a local network that was located before the terminal 100 entered the target local network 12 of the target local gateway 121 or was initially assigned a local IP address. Is described as the source local network 11.

10 is a block diagram of a source local gateway 111 that provides mobility between local networks according to an embodiment of the present invention.

Referring to FIG. 10, a source local gateway 111 providing mobility between local networks according to an exemplary embodiment of the present invention may include a local network (target local network 12) adjacent to a cell of the terminal 100. Tunnel information setting unit 101 for setting tunnel information when the cell is changed to a cell of an adjacent local base station (target local base station 122), and a local base station connected with data received from the packet data network before the cell change of the terminal 100 is performed. (Source local base station 112) to the terminal 100, and after the cell change of the terminal 100, the data received from the packet data network local gateway of the adjacent local network (target local network 12) ( And a data forwarding unit 1020 for tunneling to an adjacent local base station (target local base station 122) through the interface with the target local gateway 121 and forwarding to the terminal 100.

The above-mentioned set tunnel information may be information for tunneling data received from the packet data network to the target local base station 122 or information for tunneling data received from the packet data network to the target local gateway 121. have. Such information may include an IP address (core network IP address or local IP address) for the target local base station 122 or the target local gateway 121.

As described above, according to the present invention, mobility between local networks can be efficiently provided.

In addition, according to the present invention, while providing mobility between local networks, it is possible to reduce the traffic transmission path and reduce the traffic concentration to a specific device.

While the present invention has been described in connection with what is presently considered to be the most practical and preferred embodiments, it is to be understood that the invention is not limited to the disclosed embodiments. In other words, within the scope of the present invention, all of the components may be selectively operated in combination with one or more. In addition, although all of the components may be implemented as one independent hardware, some or all of the components may be selectively combined to perform a part or all of the functions in one or a plurality of hardware. As shown in FIG. Codes and code segments constituting the computer program may be easily inferred by those skilled in the art. Such a computer program may be stored in a computer readable storage medium and read and executed by a computer, thereby implementing embodiments of the present invention. As the storage medium of the computer program, a magnetic recording medium, an optical recording medium, a carrier wave medium, or the like may be included.

It is also to be understood that the terms such as " comprises, "" comprising," or "having ", as used herein, mean that a component can be implanted unless specifically stated to the contrary. But should be construed as including other elements. All terms, including technical and scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs, unless otherwise defined. Commonly used terms, such as predefined terms, should be interpreted to be consistent with the contextual meanings of the related art, and are not to be construed as ideal or overly formal, unless expressly defined to the contrary.

The foregoing description is merely illustrative of the technical idea of the present invention, and various changes and modifications may be made by those skilled in the art without departing from the essential characteristics of the present invention. Therefore, the embodiments disclosed in the present invention are intended to illustrate rather than limit the scope of the present invention, and the scope of the technical idea of the present invention is not limited by these embodiments. The protection scope of the present invention should be interpreted by the following claims, and all technical ideas within the equivalent scope should be interpreted as being included in the scope of the present invention.

Claims (6)

In the method of providing mobility between local networks,
Transmitting, by a source local gateway of a source local network, data received from a packet data network to a terminal through a source local base station connected to the source local gateway;
Changing the cell of the terminal from a cell of the source local base station to a cell of a target local base station connected to a target local gateway of a target local network adjacent to the source local network; And
Forwarding, by the source local gateway, the data received from the packet data network to the target local base station through the interface with the target local gateway and forwarding to the terminal;
Method for providing mobility between local networks comprising a. According to the source term,
Prior to the forwarding step,
The target local base station transmits a path switch request message to a mobility management device to inform the fact that the cell of the terminal has changed, and the mobility management device transmits a tunnel setup request message for downlink traffic forwarding to a serving gateway. The serving gateway sends a tunnel configuration change request message for downlink traffic forwarding to the source local gateway, the source local gateway sends a tunnel configuration change response message to the serving gateway, and the serving gateway responds to the tunnel configuration response. A signaling step that transmits a message to the mobility management device, the mobility management device sends a path switch request response message to the target local base station, and the target local base station notifies the source local base station that the handover was successful. How to provide inter-local network that includes more mobility. In the method of providing mobility between local networks,
Transmitting, by a source local gateway of a source local network, data received from a packet data network to a terminal through a source local base station connected to the source local gateway;
Changing the cell of the terminal from a cell of the source local base station to a cell of a target local base station connected to a target local gateway of a target local network adjacent to the source local network;
The source local gateway tunneling data received from the packet data network to the target local gateway through an interface with the target local gateway; And
Forwarding the tunneled data from the source local gateway to the target local base station by the target local gateway to the terminal;
Method for providing mobility between local networks comprising a. The method of claim 3,
Before the tunneling step,
The target local base station transmits a path switch request message for notifying that the cell of the terminal has been changed to the target local gateway, and the target local gateway transmits a session establishment request message to the source local gateway for downlink traffic forwarding. The source local gateway sends a session establishment response message to the target local gateway, the target local gateway sends a path switch response message to the target local base station, and the target local base station hands over to the source local base station And a signaling step of notifying that the operation has been successful. In a local gateway to provide mobility between local networks,
An information exchange unit for exchanging information with a local gateway of an adjacent local network through an interface between local gateways; And
Home local gateway recognition unit of the mobile terminal that recognizes the home local gateway of the terminal entering the local network through the exchanged information
Local gateway to provide mobility between local networks, including. In a local gateway to provide mobility between local networks,
A tunnel information setting unit configured to set tunnel information when a cell of a terminal is changed to a cell of a neighboring local base station of a neighboring local network; And
Before the cell change of the terminal, data received from the packet data network is transmitted to the terminal through a connected local base station, and after the cell change of the terminal, data received from the packet data network is interfaced with a local gateway of the adjacent local network. A data forwarding unit tunneling to the adjacent local base station through the terminal forwarding through
Local gateway to provide mobility between local networks, including.

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