KR102109777B1 - Method of device to device discovery and apparatus thereof - Google Patents

Abstract

Disclosed is a method and apparatus for discovery between terminals. The limited discovery method includes receiving a discovery identifier of a discovery terminal from a D2D server, performing an authentication procedure for performing a limited discovery of an application located in the discovery terminal with a D2D server, and when authentication for the application is completed, limited discovery And obtaining the searched terminal information, which is a counterpart terminal to perform, from a D2D server. Therefore, it is possible to effectively perform limited discovery.

Description

METHOD OF DEVICE TO DEVICE DISCOVERY AND APPARATUS THEREOF}

The present invention relates to a discovery technology between terminals, and more particularly, to a communication method and apparatus for effectively performing discovery between adjacent terminals.

In a cellular communication environment, a common method for terminals to transmit and receive data is through a base station. That is, when there is data to be transmitted to the second terminal, the first terminal transmits the data to the first base station to which it belongs. The first base station transmits data received from the first terminal to the second base station to which the second terminal belongs through the core network. Finally, the second base station transmits data received from the first base station to the second terminal. Here, the first base station and the second base station may be the same base station, or different base stations.

Meanwhile, device-to-device communication (D2D) means that terminals communicate directly without passing through a base station. That is, the first terminal can transmit and receive data by directly communicating with the second terminal without going through the base station.

Discovery between terminals means to discover other nearby terminals or services using a direct link between terminals, similar to direct communication between terminals.

An object of the present invention for solving the above problems is to provide a limited discovery method for effectively performing discovery between adjacent terminals.

Another object of the present invention for solving the above problems is to provide a limited discovery activation method for effectively performing discovery between adjacent terminals.

Another object of the present invention for solving the above problems is to provide a limited discovery deactivation method for effectively performing discovery between adjacent terminals.

The limited discovery method according to an embodiment of the present invention for achieving the above object comprises: receiving a discovery identifier of a discovery terminal from a D2D server, and an authentication procedure for performing limited discovery of an application located in the discovery terminal through the D2D server And performing, and acquiring, from the D2D server, searched terminal information that is a counterpart terminal to perform limited discovery when authentication for the application is completed.

Here, the discovery ID may indicate that the discovery terminal supports limited discovery.

Here, the step of performing the authentication procedure with the D2D server comprises: transmitting an authentication request message to the D2D server requesting authentication for performing limited discovery of an application located in the search terminal, and the authentication from the D2D server And receiving an authentication response message that is a response to the request message.

Here, the authentication request message may include a search terminal ID and an application ID.

Here, obtaining the searched terminal information from the D2D server comprises: transmitting a searched terminal information request message to the D2D server, and a searched terminal that is a response to the searched terminal information request message from the D2D server The method may include receiving an information response message, and updating a search terminal list based on the searched terminal information included in the searched terminal information response message.

Here, the searched terminal information request message may include a target terminal ID to be searched, an operation flag, and the application ID.

Here, the operation flag may indicate a request for consent for a limited discovery or a request for canceling the consent.

Here, the searched terminal information response message may include the searched terminal ID and response information on whether or not to restrict the discovery.

Here, if the answer to whether or not the limited discovery consent is agreed, the searched terminal ID may be added to the searched terminal list.

The limited discovery activation method according to an embodiment of the present invention for achieving the other object is to transmit a limited discovery activation request message for activating the limited discovery of the searched terminal to the D2D server, the limited of the searched terminal When discovery is activated, receiving radio resource information used for limited discovery through a base station linked with the D2D server, and receiving a limited discovery activation response message that is a response to the limited discovery activation request message from the D2D server And performing limited discovery with the searched terminal through a radio resource indicated by the radio resource information.

Here, the limited discovery activation request message may include a discovery type, a discovery state, an application identifier of the discovery terminal, and a discovery terminal ID.

Here, the limited discovery activation response message may include the discovery ID of the discovery terminal and the discovery ID of the discovery terminal.

Here, when the limited discovery activation response message is received, the discovery terminal may transition to the limited discovery activation state.

Here, when the limited discovery activation request message is received, the D2D server may allocate radio resources used for limited discovery to the searched terminal.

Here, when the allocation of radio resources used for discovery limited to the searched terminal is completed, the D2D server may set the discovery ID of the search terminal and the discovery ID of the searched terminal.

Here, a message transmitted between the discovery terminal and the D2D server may be transmitted through a mobile management entity.

The limited discovery deactivation method according to an embodiment of the present invention for achieving the above another object includes transmitting a limited discovery deactivation request message for deactivating limited discovery of the searched terminal to a D2D server, When the limited discovery is deactivated, receiving a release of a radio resource allocated for limited discovery from a base station associated with the D2D server, and receiving a limited discovery deactivation response message, which is a response to the limited discovery deactivation request message, from the D2D server. And receiving, and transitioning to an idle state.

Here, when the limited discovery deactivation request message is received, the D2D server may release the radio resource allocated to the searched terminal for limited discovery.

Here, when the release of radio resources allocated to the searched terminal is completed, the D2D server may release the discovery ID set for the searched terminal.

Here, when the release of the radio resource allocated to the discovery terminal is completed, the D2D server may release the discovery ID set for the discovery terminal.

According to the present invention, it is possible to effectively perform limited discovery.

1 is a conceptual diagram illustrating a D2D discovery-related operation scenario.
2 is a conceptual diagram illustrating a shared spectrum operation method for D2D discovery and communication.
3 is a conceptual diagram illustrating a dedicated spectrum scheme shared by multiple operators for D2D discovery and communication.
4 is a conceptual diagram showing a functional structure for D2D discovery.
5 is a conceptual diagram illustrating an LTE network structure for D2D discovery.
6 is a conceptual diagram illustrating a functional structure of a user terminal for D2D discovery when the DMF operates as a function of a control plane.
7 is a conceptual diagram illustrating a protocol interworking structure for D2D discovery when the D2D server operates as a function of a control plane.
8 is a conceptual diagram illustrating a functional structure of a user terminal for D2D discovery when the DMF operates as a user plane function.
9 is a conceptual diagram illustrating a protocol interworking structure for D2D discovery when the D2D server operates as a user plane function.
10 is a conceptual diagram illustrating channel mapping for a D2D discovery message transmission and reception procedure.
11 is a conceptual diagram illustrating a D2D discovery transmission and reception state.
12 is a flowchart illustrating an authentication procedure of a limited discovery application using a control plane function.
13 is a flowchart illustrating an authentication procedure of a limited discovery application using a user plane function.
14 is a flowchart illustrating a limited discovery consent and consent cancellation procedure using a control plane function.
15 is a flowchart illustrating a limited discovery consent and consent cancellation procedure using a user plane function.
16 is a flowchart illustrating a procedure (S200 to S210) for activation of a limited discovery service using a control plane.
FIG. 17 is a flowchart illustrating a procedure (S211 to S228) for activating a limited discovery service using a control plane.
18 is a flowchart illustrating a procedure for deactivating limited discovery services using a control plane (S250 to S261).
19 is a flow chart showing a procedure of deactivation of a limited discovery service using a control plane (S261 to S273).
20 is a flowchart illustrating a procedure (S300 to S313) for activating a limited discovery service using a user plane.
FIG. 21 is a flowchart illustrating a procedure (S314 to S326) for activating a limited discovery service using a user plane.
22 is a flowchart illustrating a procedure for deactivating a limited discovery service using a user plane.
23 is a flowchart illustrating a discovery event using a control plane and a procedure for reporting discovered information.
24 is a flowchart illustrating a discovery event using a user plane and a procedure for reporting discovered information.
25 is a flowchart illustrating a procedure for exchanging discovery setting information between D2D servers for limited discovery using a control plane function (S500 to S514).
26 is a flow diagram illustrating discovery setting information exchange procedures (S515 to S533) between D2D servers for limited discovery using a control plane function.
27 is a flowchart illustrating a procedure for exchanging discovery setting information between D2D servers for limited discovery using a user plane function (S600 to S610).
FIG. 28 is a flow diagram illustrating discovery procedure information exchange procedures (S611 to S623) between D2D servers for limited discovery using a user plane function.
29 is a conceptual diagram illustrating an embodiment (globally unique discovery ID) of a discovery message configuration for limited discovery.
30 is a conceptual diagram illustrating another embodiment (locally unique discovery ID) of a discovery message configuration for limited discovery.
31 is a conceptual diagram illustrating the definition of a protocol message for D2D discovery.
32 is a conceptual diagram illustrating definition of another protocol message for D2D discovery.
33 is a conceptual diagram illustrating parameter definition of a protocol message for D2D discovery.

The present invention can be applied to various changes and can have various embodiments, and specific embodiments will be illustrated in the drawings and described in detail.

However, this is not intended to limit the present invention to specific embodiments, and should be understood to include all modifications, equivalents, and substitutes included in the spirit and scope of the present invention.

Terms such as first and second may be used to describe various components, but the components should not be limited by the terms. The terms are used only for the purpose of distinguishing one component from other components. For example, the first component may be referred to as a second component without departing from the scope of the present invention, and similarly, the second component may be referred to as a first component. The term and / or includes a combination of a plurality of related described items or any one of a plurality of related described items.

When an element is said to be "connected" or "connected" to another component, it is understood that other components may be directly connected to or connected to the other component, but there may be other components in between. It should be. On the other hand, when a component is said to be "directly connected" or "directly connected" to another component, it should be understood that no other component exists in the middle.

The terms used in the present application are only used to describe specific embodiments, and are not intended to limit the present invention. Singular expressions include plural expressions unless the context clearly indicates otherwise. In this application, terms such as “include” or “have” are intended to indicate that a feature, number, step, operation, component, part, or combination thereof described in the specification exists, one or more other features. It should be understood that the existence or addition possibilities of fields or numbers, steps, operations, components, parts or combinations thereof are not excluded in advance.

Unless defined otherwise, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by a person skilled in the art to which the present invention pertains. Terms such as those defined in a commonly used dictionary should be interpreted as having meanings consistent with meanings in the context of related technologies, and should not be interpreted as ideal or excessively formal meanings unless explicitly defined in the present application. Does not.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In order to facilitate the overall understanding in describing the present invention, the same reference numerals are used for the same components in the drawings, and duplicate descriptions for the same components are omitted.

Throughout the specification, the network includes, for example, wireless Internet such as WiFi (Wireless Fidelity), mobile Internet such as Wireless Broadband Internet (WiBro) or World Interoperability for Microwave Access (WiMax), Global System for Mobile communication (GSM). ) Or 2G mobile networks such as Code Division Multiple Access (CDMA), 3G mobile networks such as Wideband Code Division Multiple Access (WCDMA) or CDMA2000, High Speed Downlink Packet Access (HSDPA) or High Speed Uplink Packet Access (HSUPA) It may include a 3.5G mobile communication network, a LTE (Long Term Evolution) network or a 4G mobile communication network such as LTE-Advanced network, and a 5G mobile communication network.

Throughout the specification, communication networks include, for example, 2G mobile networks such as Global System for Mobile communication (GSM), Code Division Multiple Access (CDMA), wireless Internet such as Wireless Fidelity (WiFi), Wireless Broadband Internet (WiBro) and WiMax (Internet Interoperability for Microwave Access) or a mobile communication network supporting packet transmission (e.g., Wideband Code Division Multiple Access (WCDMA) or 3G mobile communication network such as CDMA2000, High Speed Downlink Packet Access (HSDPA) or High HSUPA) 3.5G mobile communication network such as Speed Uplink Packet Access), 4G mobile communication network such as LTE (Long Term Evolution) network, or LTE-Advanced network).

Throughout the specification, a device is a mobile station, a mobile terminal, a subscriber station, a portable subscriber station, a user equipment, and an access terminal. It may also refer to a terminal, a mobile station, a mobile terminal, a subscriber station, a mobile subscriber station, a user device, and may include all or part of functions such as an access terminal.

Here, a desktop computer capable of communicating with a terminal, a desktop computer, a laptop computer, a tablet PC, a wireless phone, a mobile phone, a smart phone, and e- book reader, portable multimedia player (PMP), portable game machine, navigation device, digital camera, digital multimedia broadcasting (DMB) player, digital audio recorder, digital audio player ), A digital picture recorder, a digital picture player, a digital video recorder, a digital video player, and the like.

Device-to-device communication (D2D) discovery refers to a procedure in which a specific terminal discovers a nearby terminal / service based on a signal received using radio resources. To this end, terminals / services that want to be discovered by adjacent terminals / services can transmit predefined messages using radio resources configured for D2D discovery, and terminals that want to discover neighboring terminals can use these radio resources. It is possible to receive the discovery message transmitted through.

The scope of D2D discovery can be broadly classified into service level discovery and terminal level discovery. Service level discovery refers to discovery of services provided by peripheral terminals, and terminal level discovery refers to discovery of identifiers (IDs) of peripheral terminals.

D2D discovery described in the present invention includes both service level discovery and terminal level discovery. In addition, a terminal that wants to be discovered by neighboring terminals is defined as a discoverable UE, and a terminal that wants to discover neighboring terminals is defined as a discovery UE.

The D2D discovery function can be classified into a commercial use case and a public safety use case, and the requirements related to the D2D discovery are as follows.

● D2D Discovery Requirements for Commercial Use Cases

-Restricted discovery

· Discovery performed only with the consent of the discovered terminal

Examples: social networking service (SNS), evolved packet system (EPS), proSe (proximity service) discovery

-Open discovery

· Discovery without the consent of the terminal being discovered

· Examples: advertising services, mobile games

-Discovery function (capability)

· Ability to discover other nearby terminals

· Ability to be discovered by other nearby terminals

-Discovery with subscribers from other public land mobile networks (PLMNs)

· Discovery between terminals belonging to different PLMNs

-Discovery with roaming subscribers

· Discovery of a terminal roaming in another network

● D2D Discovery Requirements for Public Safety Use Cases

-Discovery within network coverage

· Discovery of terminals located within an operator network coverage

-Discovery outside the network

· Discovery of terminals located outside the operator's network

In addition, the requirements for authorization and charging for D2D discovery are as follows.

● Approval

-Approval of discovery operations for each terminal

-Approval of the terminal to be discovered by other terminals

-Approval of the terminal discovering other terminals

● Billing

-Ability for terminals to be discovered

-Ability to discover other terminals

-Event for terminal discovery

On the other hand, the main requirements presented in the direct communication between terminals (ie, direct discovery wireless aspects) are as follows.

● Supervision of D2D discovery process

-Supervision by network operators

-For scenarios outside the network, supervision by a specific terminal

● Spectrum Aspects

-LTE frequency division duplex (FDD) and LTE time division duplex (TDD) operation

-Dedicated spectrum shared by multiple operators

-Shared spectrum operations

1 is a conceptual diagram illustrating a D2D discovery-related operation scenario.

Referring to FIG. 1, D2D discovery-related operation scenarios include inter-operator discovery scenarios, intra-cell discovery scenarios, inter-cell discovery scenarios, and discovery for roaming terminals. Scenarios, etc. exist.

Spectrum usage methods for D2D discovery and communication may be classified into a shared spectrum operation method and a dedicated spectrum method shared by multiple operators.

2 is a conceptual diagram illustrating a shared spectrum operation method for D2D discovery and communication.

2, the characteristics of the shared spectrum operation method are as follows.

● D2D discovery is performed using a part of the cellular spectrum allocated to each mobile operator network

-Share the same carrier with cellular communication, or use a separate carrier for D2D discovery and communication

● D2D discovery setup and control, authentication and charging for D2D discovery, and D2D discovery procedures are done through each operator network

In the case of the shared spectrum operation method, in order to discover UEs subscribed to another operator's network, the UE uses system information block (SIB) for setting information of D2D discovery radio resources used in other networks as well as itself in the network to which it is subscribed. Can be received through. The device to be searched can transmit a discovery message through the frequency spectrum of the provider to which it is subscribed. The discovery terminal may receive at least one discovery message through its own or another operator spectrum, and may perform a D2D discovery procedure based on the received discovery message.

For D2D discovery between terminals joining different operator networks, the terminal must be equipped with a receiver that can receive network signals from other operators, otherwise the discovery radio resources allocated in each operator network must be orthogonal in time. do. Also, by exchanging D2D discovery radio resource configuration information, operator networks can support D2D discovery between terminals that have joined other operator networks.

3 is a conceptual diagram illustrating a dedicated spectrum scheme shared by multiple operators for D2D discovery and communication.

Referring to FIG. 3, a dedicated spectrum method shared by multiple operators is as follows.

● For D2D discovery and communication, D2D discovery is performed using independent spectrum shared by multiple mobile operators.

● D2D discovery setup and control, authentication and charging procedures for D2D discovery are done through the cellular spectrum

When a plurality of operators share and use a common spectrum for D2D discovery and communication, the UE can receive configuration information of a D2D discovery radio resource used in the common shared spectrum through SIB or the like from the network to which it is subscribed. have. The searched terminal may transmit a discovery message through a common shared spectrum. The discovery terminal may receive at least one discovery message through the same spectrum (ie, a common shared spectrum), and may perform a D2D discovery procedure based on the received discovery message.

At this time, each terminal must be equipped with a receiver capable of receiving a signal through a common spectrum, and carrier networks must share radio resource configuration information of a common D2D discovery spectrum.

In order to satisfy the requirements related to D2D discovery described above, the LTE system defines an additional functional entity for D2D discovery, and provides a D2D discovery feature using the same. To this end, the present invention introduces a D2D server and a DMF (dicovery management function), which are functional entities and function modules that manage D2D discovery functions.

4 is a conceptual diagram showing a functional structure for D2D discovery.

Referring to FIG. 4, the D2D server is a functional entity located in the LTE network for discovery service. DMF is a function module located in a terminal and managing a discovery function in conjunction with a D2D server.

The D2D server may perform generation and issuance of a discovery ID, storage of discovery-related information of a terminal, exchange of information for D2D discovery between mobile communication providers, and interworking procedures between existing LTE function entities. The D2D server is a functional entity that performs a control function for D2D discovery, and may exist as an independent functional entity of the LTE network. In addition, one mobile communication provider may provide a D2D discovery service using at least one D2D server. In addition, interfaces between D2D servers may be provided for discovery services between operators, and D2D servers may perform exchange of configuration information related to discovery using these interfaces.

In the present invention, a form in which a D2D server exists as one independent functional entity and each mobile communication provider provides a D2D discovery service using one logical D2D server is considered.

5 is a conceptual diagram illustrating an LTE network structure for D2D discovery.

Referring to FIG. 5, the D2D server may interwork with other functional entities (eg, HSS, PDN GW) of the LTE network using an additional reference point such as Sxx or Gyy.

The DMF located in the terminal may store discovery-related information, and by using this, a D2D discovery procedure may be performed in conjunction with an LTE protocol function and a D2D discovery application to which a D2D discovery-related function is added. Similar to the D2D server described above, DMF may be included in the existing protocol function of the terminal or may exist as an independent function. In the present invention, it is assumed that the DMF exists as a function independent of the terminal.

In the present invention, the DMF and D2D servers may operate as a control plane function or a user plane function. When the DMF and D2D servers operate as a control plane function, the functions of the DMF and D2D servers are included in the NAS (non access stratum) protocol level or NAS protocol, and operate in conjunction with the control plane protocol of the LTE function node. When the DMF and D2D servers operate as a user plane function, the DMF and D2D servers are located at the application level and exchange control information related to D2D discovery through the user plane.

6 is a conceptual diagram illustrating a functional structure of a user terminal for D2D discovery when the DMF operates as a function of a control plane.

Referring to FIG. 6, RRC +, MAC +, and PHY + layers among protocol stacks for D2D discovery may mean that additional functions for D2D discovery are included.

7 is a conceptual diagram illustrating a protocol interworking structure for D2D discovery when the D2D server operates as a function of a control plane.

Referring to FIG. 7, the NAS layer of the terminal (UE) interworks with the NAS layer of a mobility management entity (MME), and the general packet radio service tunneling protocol-control plane (GTP-C) layer of the MME is a D2D server (HPLMN). Discovery mngt. Interworking with the layer, discovery mngt of the D2D server (HPLMN). The layer is the discovery mngt of the D2D server (VPLMN). Interwork with layers.

8 is a conceptual diagram illustrating a functional structure of a user terminal for D2D discovery when the DMF operates as a user plane function.

Referring to FIG. 8, among the protocol stacks for D2D discovery, the RRC +, MAC +, and PHY + layers may mean that additional functions for D2D discovery are included.

9 is a conceptual diagram illustrating a protocol interworking structure for D2D discovery when the D2D server operates as a user plane function.

Referring to FIG. 9, an application layer of a UE is a discovery mngt of a D2D server (HPLMN). Interworking with the layer, discovery mngt of the D2D server (HPLMN). The layer is the discovery mngt of the D2D server (VPLMN). Interwork with layers.

10 is a conceptual diagram illustrating channel mapping for a D2D discovery message transmission and reception procedure.

Referring to FIG. 10, newly defined device discovery channel (DDCH), discovery channel (DCH), and physical discovery channel (PDCH) may be used for transmission and reception of a discovery message between terminals.

When the DMF operates as a function of a control plane, a control protocol procedure for D2D discovery may use an existing hierarchical structure and an uplink / downlink channel of the LTE system. That is, a DCCH (dedicated control channel) on the downlink, a downlink-shared channel (DL-SCH) and a physical downlink shared channel (PDSCH) can be used, and the DCCH, the uplink-shared channel (UL-SCH) and the PUSCH on the uplink. (physical uplink shared channel) can be used.

When the DMF operates as a function of a user plane, a control protocol procedure for D2D discovery may use the existing hierarchical structure and uplink / downlink channels of the LTE system. That is, a downlink traffic channel (DTCH), DL-SCH, and PDSCH can be used, and uplink DTCH, UL-SCH, and PUSCH can be used.

In addition to the D2D server and DMF described above, a mobile communication provider can provide a discovery interface server and a discovery application for subscription, registration, and setup of a user's D2D discovery service. The discovery interface server and discovery application refer to functional objects and terminal applications located outside the operator network provided by each operator for D2D discovery. The discovery interface server and the discovery application are one operating method provided by a mobile communication provider to provide a discovery service.

The D2D server and the DMF may manage states related to D2D discovery.

11 is a conceptual diagram illustrating a D2D discovery transmission and reception state.

Referring to FIG. 11, an idle state means a state in which a procedure related to D2D discovery is not performed, and a discovery state means a state in which a discovery message for D2D discovery is received. The discoverable state means a state in which a discovery message for D2D discovery is transmitted, and the 'discovery & discovery possible' state means a state in which a discovery message for D2D discovery is transmitted and received.

Restricted discovery

The limited discovery procedure is a procedure for discovering a terminal based on mutual consent between the discovery terminal and the searched terminal. To this end, the terminal can perform procedures such as generating and issuing limited discovery information, authenticating a limited discovery application, and agreeing to and disabling the limited discovery of the terminal to be searched, and performing a procedure for limited discovery. The limited discovery procedure means a procedure of transmitting and receiving a discovery message and recognizing a corresponding terminal using the received discovery message, and the terminal completing the discovery procedure reports information obtained through the discovery procedure and events related to discovery Can be performed.

In performing the limited discovery procedure described above, terminals managed by different operators or different D2D servers may perform a limited discovery procedure including interworking procedures between D2D servers.

The following describes the operation procedure by dividing the case where the D2D discovery operates as a function of the control plane and the case of operating as a function of the user plane.

Each functional entity for limited discovery can perform the following functions.

◈ D2D server (network)

* function

-Discovery ID creation and issuance

-3rd party application authentication

-Discovery information management (terminal ID, discovery ID, discovery range class)

-Discovery setting information management (discovery type (discovery type), discovery status)

-Terminal ID management agreed to the limited discovery service

-Intermediate limited discovery information in conjunction with other D2D servers

-Manage discovered information

-Protocol procedure for D2D discovery in conjunction with DMF

-Interworking with LTE network function entities (eg MME, eNB, HSS (home subscriber server)) (authentication, charging)

* Storage information

-Terminal ID, Discovery ID, Discovery Range Class

-Discovery type, discovery status

-List of terminal IDs that have agreed to the limited discovery service

-Discovery information reported as a result of D2D discovery

-3rd party application contract information

◈ DMF (terminal)

* function

-Save and manage your own Discovery ID

-Searchable terminal ID management (terminal ID, discovery ID)

-3rd party application authentication support

-Generation and transmission of limited discovery messages

-Receive and interpret limited discovery messages

-Report ID and billing information recognized through D2D discovery process

-Perform protocol procedure for D2D discovery in conjunction with D2D server

-Interworking with discovery-related applications and LTE terminal protocols

* Storage information

-Your Discovery ID assigned when you request Discovery

-Discovery ID of a searchable terminal assigned when a discovery request is requested

-Searchable terminal list

Creation and issuance of limited discovery information

The limited discovery information generation and issuance procedure may include a process in which a mobile communication provider generates and issues a discovery ID for a limited discovery service, and a terminal stores the discovery ID.

Generation and issuance of a discovery ID for limited discovery may be performed when the terminal is opened or required (for example, when a D2D discovery service is subscribed or when a D2D discovery service is requested). When performing such a procedure, the D2D server may issue the discovery ID of the subscribed terminal, and store and manage the discovery ID and the terminal ID of the corresponding terminal. The terminal may store a discovery ID issued by a mobile communication provider.

The discovery ID issued according to the above procedure is an ID that cannot be recognized as a specific user, and can be used when transmitting limited discovery information. In addition, the open discovery and the limited discovery service can share and use the same discovery ID.

● Classification of limited discovery ID generation and issuance

-When a user terminal joins (opens) a specific mobile communication provider, it is created and issued by a D2D server

-When a user terminal subscribes to a D2D discovery service or requests a D2D discovery service, it is created and issued by the D2D server

The terminal may subscribe to the limited discovery service according to the user's request. That is, the user can access the discovery interface server of the mobile communication provider through an application or a PC of the terminal, and subscribe or unsubscribe from the limited discovery service.

In the operation procedure described above, a method in which a D2D server generates and issues a discovery ID when a UE subscribes to a D2D discovery service and requests a discovery service is described. However, when the user terminal joins (opens) a specific mobile communication provider, it is also possible for the D2D server to generate and issue a discovery ID.

Limited discovery application authentication

Limited discovery application authentication refers to an authentication procedure performed by applications located in a terminal to use a limited discovery feature. This authentication procedure refers to an authentication procedure for whether a specific application developed by a 3rd party developer can use a limited discovery function. To this end, the 3rd party developer must sign a contract with the mobile communication service provider for the use of the limited discovery function of the application in advance. The authentication procedure for using a limited discovery service of a specific application may be performed only when the application is used for the first time or whenever the application is executed according to the setting of the operator network.

In the authentication procedure, it is possible to consider the case where the terminal exists in the subscribed network and the case where the terminal exists in the roamed operator network. When present in the roaming operator network, an authentication procedure may be performed through interworking between D2D servers.

12 is a flowchart illustrating an authentication procedure of a limited discovery application using a control plane function.

Referring to FIG. 12, the first terminal 10 may transmit an authentication request message (APP_DISCOVERY_FEATURES_REQ) to the MME 40 (S100), and the MME 40 receives the authentication request message received from the first terminal 10. It can be transmitted to the first D2D server 60 (S101). The authentication request message means a message for requesting authentication for use of a limited discovery service of an application, and may include application ID (app. Id.), First terminal ID information, and the like.

The first D2D server 60 may perform approval / authentication for the application based on the information included in the authentication request message (S102). After the approval / authentication for the application is completed, the first D2D server 60 may transmit an authentication response message (APP_DISCOVERY_FEATURES_RSP) including the approval / authentication result information to the MME 40 (S103). The MME 40 may transmit the authentication response message received from the first D2D server 60 to the first terminal 10 (S104). The authentication response message means an authentication response message for use of a limited discovery service of an application, and may include result, cause information, and the like.

13 is a flowchart illustrating an authentication procedure of a limited discovery application using a user plane function.

Referring to FIG. 13, the first terminal 10 may transmit an authentication request message (APP_DISCOVERY_FEATURES_REQ) to the first D2D server 60 (S110). The authentication request message means a message for requesting authentication for use of a limited discovery service of an application, and may include application ID, first terminal ID information, and the like. The first D2D server 60 may perform approval / authentication for the application based on the information included in the authentication request message (S111). After the approval / authentication for the application is completed, the first D2D server 60 may transmit an authentication response message (APP_DISCOVERY_FEATURES_RSP) including the approval / authentication result information to the first terminal 10 (S112). The authentication response message means an authentication response message for use of a limited discovery service of an application, and may include results, cause information, and the like.

Limited discovery consent and disagreement

The limited discovery consent and consent cancellation procedure refers to a procedure for obtaining mutual agreement between terminals for a limited discovery service or canceling the established agreement. For the limited discovery consent procedure, the discovery application may perform an agreement procedure for the limited discovery service at the application level, and then instruct the DMF to perform the limited discovery agreement procedure with the opposite terminal.

The DMF, which is instructed to perform the limited discovery consent procedure, may transmit a consent request message including the ID of the target terminal requesting the consent request and an operation flag (set or clear) to the D2D server. The D2D server may transmit the consent request message received from DMF to the target terminal, and receive a response message to the consent request message from the target terminal.

In the limited discovery consent and consent cancellation procedure, the action flag is set to set when requesting consent, and the action flag is set to clear when requesting to cancel consent. When the response message for the consent request message is received from the target terminal, the D2D server may update the list of searched terminals when the target terminal accepts the consent request based on the information included in the response message, and the response The message can be transmitted to the DMF of the search terminal. The DMF of the discovery terminal requesting the consent of the limited discovery and the cancellation of the consent may update the list of the searched terminal based on the response message to the consent request message.

14 is a flowchart illustrating a limited discovery consent and consent cancellation procedure using a control plane function.

Referring to FIG. 14, the first terminal 10 (that is, the discovery terminal) can transmit a searchable ID request message (DISCOVERABLE_ID_REQ) to the MME 40 (S120), and the MME 40 is the first terminal 10 ) Can transmit the searchable ID request message received from the first D2D server 60 (S121). The searchable ID request message means a message requesting to add a searched terminal list, and may include a target terminal ID (ie, a second terminal ID), an operation flag, application ID information, and the like. have.

The first D2D server 60 may transmit an invitation request message (INVITE_REQ) for the limited discovery consent to the MME 40 (S122), and the MME 40 invite request message received from the first D2D server 60 It may be transmitted to the second terminal 20 that is the target terminal (S123). The invitation request message refers to a request message used to add a terminal to the searched terminal list, and may include a first terminal ID, an operation flag, a target terminal ID, and application ID information.

The second terminal 20 may decide to agree or release consent for the limited discovery based on the received invitation request message, and may transmit an invitation response message (INVITE_RSP) including the determined result information to the MME 40 (S124) ). The MME 40 may transmit the invitation response message received from the second terminal 20 to the first D2D server 60 (S125). The invitation response message means a response message used to add the terminal to the searched terminal list, and may include a result, cause information, and the like. Meanwhile, the second terminal 20 may update the list of terminals to be searched based on the result information determined by the user (that is, consent or release of consent for limited discovery) (S126).

The first D2D server 60 may generate a searchable ID response message (DISCOVERABLE_ID_RSP) based on information included in the invitation response message received from the second terminal 20, and the searchable ID response message MME 40 ) (S127). The MME 40 may transmit the searchable ID response message received from the first D2D server 60 to the first terminal 10 (S128). The searchable ID response message means a response message for adding a terminal to the searched terminal list, and may include a result, a cause, and target terminal ID information.

Meanwhile, the first D2D server 60 may update the searched terminal list based on information included in the searchable ID response message (S129), and the first terminal 10 may also be included in the searchable ID response message. Based on the information, the searched terminal litts may be updated (S130).

15 is a flowchart illustrating a limited discovery consent and consent cancellation procedure using a user plane function.

15, the first terminal 10 (that is, the discovery terminal) may transmit a searchable ID request message (DISCOVERABLE_ID_REQ) to the first D2D server 60 (S140). The searchable ID request message means a message requesting the addition of a searched terminal list, and may include a target terminal ID (ie, a second terminal ID), an operation flag, application ID information, and the like.

The first D2D server 60 may transmit an invitation request message (INVITE_REQ) for the limited discovery agreement to the second terminal 20, which is the target terminal (S141). The invitation request message refers to a request message used to add a terminal to the searched terminal list, and may include a first terminal ID, an operation flag, a target terminal ID, and application ID information.

The second terminal 20 may decide to agree or release consent for the limited discovery based on the received invitation request message, and transmit an invitation response message (INVITE_RSP) including the determined result information to the first D2D server 60 Yes (S142). The invitation response message means a response message used to add the terminal to the searched terminal list, and may include a result, cause information, and the like. Meanwhile, the second terminal 20 may update the terminal list to be searched based on the result information determined by the user (that is, consent or release of consent for limited discovery) (S143).

The first D2D server 60 may generate a searchable ID response message (DISCOVERABLE_ID_RSP) based on information included in the invitation response message received from the second terminal 20, and the searchable ID response message from the first terminal It can be transmitted to (10) (S144). The searchable ID response message means a response message for adding a terminal to the searched terminal list, and may include a result, a cause, and target terminal ID information.

Meanwhile, the first D2D server 60 may update the searched terminal list based on information included in the searchable ID response message (S145), and the first terminal 10 may also be included in the searchable ID response message. Based on the information, the searched terminal litts may be updated (S146).

Limited discovery service for specific terminals

The limited discovery service for a specific terminal means limited discovery that discovers a user-specified terminal. This procedure starts when an application requests discovery for a specific terminal, and a discovery service can be performed for a period of time through a mode setting or the like until a request to release discovery by the application is performed. In addition, through this procedure, the terminal requesting discovery as well as the discovery target terminal can discover (ie, confirm that they are in close proximity) to the other terminal.

The limited discovery service may use a control plane or a user plane, and each case will be described below.

Limited discovery using control planes

An operation procedure (enable / disable) for a limited discovery service using a control plane will be described. When a D2D discovery service is provided using a control plane, the DMF of the terminal may operate in conjunction with a D2D server through eNB / MME, serving-gateway (S-GW) / packet data network-gateway (P-GW). have. Here, a terminal to discover a specific terminal is defined as a first terminal (ie, a search terminal), and a discovery target terminal is defined as a second terminal (ie, a searched terminal). In addition, the procedure described below assumes that both the first terminal and the second terminal start in an idle state.

FIG. 16 is a flow chart showing the activation procedures (S200 to S210) of the limited discovery service using the control plane, and FIG. 17 is a flow chart showing the activation procedures (S211 to S228) of the limited discovery service using the control plane.

16 and 17, a procedure for activating a limited discovery service using a control plane is as follows.

In order to activate the limited discovery service, the DMF of the first terminal 10 MME the discovery activation request message (ACTIVATE DISCOVERY REQ) including information such as discovery type, discovery status, second terminal ID, application ID (app id), etc. It can be transmitted to (40) (S200). When the discovery activation message for a specific terminal is received from the first terminal 10, the MME 40 may determine whether to perform discovery of the requested first terminal 10 and the second terminal 20 (S201). That is, the MME 40 may determine whether to perform discovery using the serving cell and location information of the first terminal 10 and the second terminal 20. When discovery is possible, the MME 40 may transmit an activation request message for the limited discovery service to the first D2D server 60 (S202).

When the discovery activation request message is received from the MME 40, the first D2D server 60 may check whether the limited discovery service is agreed between the first terminal 10 and the second terminal 20. If there is no mutual consent for the limited discovery service, a peer invitation procedure may be performed between the first D2D server 60 and the second terminal 20 (S203). If there is mutual consent for limited discovery, the first D2D server 60 does not perform the peer invitation procedure.

After performing the above procedure, the first D2D server 60 may transmit a discovery request message (REQ DISCOVERY ACTIVATION) to the MME 40 to which the second terminal 20 belongs (S204). The MME 40 may transmit the received discovery request message to the DMF of the second terminal 20 (S205). The discovery request message may include a discovery type, discovery status, cause, first terminal ID, and application ID information.

When the discovery request message is received, the DMF of the second terminal 20 may perform a response procedure to the discovery request. When accepting discovery indicated by the network, the DMF of the second terminal 20 may transmit a discovery activation request message (ACTIVATE DISCOVERY REQ) to the MME 40 (S206). The MME 40 may transmit the received discovery activation request message to the first D2D server 60 (S207). On the other hand, if the network does not accept the discovery, the DMF of the second terminal 20 may transmit a message to reject the discovery activation request including the reason code to the MME 40. The MME 40 may transmit the received discovery activation request rejection message to the first D2D server 60.

When the discovery activation request message is received from the second terminal 20, the first D2D server 60 may perform a discovery resource setting procedure to be used by the second terminal 20. For discovery resource setup, the first D2D server 60 may transmit a discovery resource setup request message (DISCOVERY_SETUP_REQ) to the MME 40 (S208). Upon receiving the discovery resource setting request message, the MME 40 may instruct the eNB 30 to allocate a discovery channel (S209). The discovery resource setting request message may include a second terminal ID, discovery status information, and the like.

When a discovery channel allocation request is received from the MME 40, the radio resource control function of the eNB 30 may perform a discovery channel allocation procedure together with the second terminal 20 (S210). The discovery channel allocation procedure performed by the eNB 30 for the second terminal 20 is a process in which the second terminal 20 measures reception characteristics of discovery channels set by the system, and the second terminal 20 measures The second terminal 20 based on the process of selecting the discovery candidate channel (s) to transmit the discovery message based on the received reception characteristics and reporting it to the eNB 30 and the discovery candidate channel (s) reported by the eNB 30 ) May include a process of designating a radio resource to be used.

After completing the discovery channel allocation request procedure, the eNB 30 may transmit a discovery resource setup response message (DISCOVERY_SETUP_RSP) including the result of discovery channel allocation, cause information, etc. to the MME 40 (S211). The MME 40 may transmit the received discovery resource setting response message to the first D2D server 60 (S212).

The first D2D server 60 may set a discovery ID for the first terminal 10 and the second terminal 20 (S213). The first D2D server 60 may transmit a limited discovery activation response message (ACTIVATE DISCOVERY RSP) including the discovery ID of the first terminal 10 and discovery ID information of the second terminal 20 to the MME 40. (S214). The MME 40 may transmit the received limited discovery activation response message to the DMF of the second terminal 20 (S215). When the limited discovery activation response message is received, the DMF of the second terminal 20 may transition to a 'discoverable & discovery' state (S216), and then start a transmission and reception procedure of the discovery message (S225) , S226, S227).

After the discovery activation procedure of the second terminal 20 is completed, the first D2D server 60 may perform a discovery resource setting procedure and a discovery channel allocation procedure for the first terminal 10 (S217, S218, S219) , S220, S221). The discovery resource setting procedure and discovery channel allocation procedure for the first terminal 10 may be the same as the discovery resource setup procedure and discovery channel allocation procedure for the second terminal 20 described above.

Thereafter, the first D2D server 60 may transmit a limited discovery activation response message including the discovery ID of the first terminal 10 and the discovery ID of the second terminal 20 to the MME 40 (S222). . The MME 40 may transmit the received limited discovery activation response message to the first terminal 10 (S223).

When the limited discovery activation response message is received, the first terminal 10 may transition to the 'discoverable & discoverable' state (S224), and then perform a transmission / reception procedure of the discovery message (S225, S227, S228) ).

That is, the DMF of the terminal (1st terminal 10 or the 2nd terminal 20) transitioned to the 'searchable & searched' state can search for a set radio resource and receive a discovery message, included in the discovery message It can be confirmed whether the discovery ID corresponds to the discovery ID received by the above procedure. When the discovery ID included in the discovery message corresponds to the discovery ID received by the above procedure, the DMF of the terminal may transmit limited discovery indication information to the application. On the other hand, if the discovery ID included in the discovery message does not correspond to the discovery ID received by the above procedure, the DMF of the terminal may discard the discovery message.

18 is a flowchart illustrating a procedure for deactivating limited discovery services using a control plane (S250 to S261), and FIG. 19 is a flowchart illustrating a procedure for deactivating limited discovery services using a control plane (S261 to S273).

18 and 19, a procedure of deactivating limited discovery using a control plane is as follows.

For the procedure of deactivating the limited discovery service using the control plane, the DMF of the first terminal 10 may transmit a discovery deactivation request message (DEACTIVATE DISCOVERY REQ) to the MME 40 (S250). The MME 40 may transmit the discovery deactivation request message received from the first terminal 10 to the first D2D server 60 (S251). The first D2D server 60 may request discovery deactivation to the second terminal 20 (REQ DISCOVERY DEACTIVATION) based on the discovery deactivation request message (S252, S253), and the second terminal 20 request discovery deactivation In response, a discovery deactivation request message (DEACTIVATE DISCOVERY REQ) may be transmitted to the first D2D server 60 (S254, S255). Here, message transmission between the second terminal 20 and the first D2D server 60 may be performed through the MME 40.

Thereafter, the first D2D server 60 may perform a procedure of releasing radio resources allocated to the second terminal 20 for deactivation of the limited discovery service of the second terminal 20. That is, the first D2D server 60 may transmit a discovery release request message (DISCOVERY_RELEASE_REQ) requesting the release of radio resources to the MME 40 (S256). The MME 40 may transmit a discovery release request message received from the first D2D server 60 to the eNB 30 (S257). The discovery release request message may include a terminal ID and discovery status information. The eNB 30 may perform a radio resource release procedure with the second terminal 20 based on the information included in the discovery release request message (S258, S259).

When the release of the radio resource is completed, the eNB 30 may transmit a discovery release response message (DISCOVERY_RELEASE_RSP) to the MME 40 (S260). The MME 40 may transmit the discovery release response message received from the eNB 30 to the first D2D server 60 (S261). The discovery release response message means a response message to a radio resource release request, and may include a result of radio resource release, cause information, and the like.

When the procedure for releasing radio resources is completed, the first D2D server 60 may release the setting of the discovery ID allocated for the second terminal 20 (S262). After the above procedure is finished, the first D2D server 60 transmits a discovery disable response message (DEACTIVATE DISCOVERY RSP) to the second terminal 20 in response to the discovery disable request message received from the second terminal 20 It can be (S263). The discovery deactivation response message means a response message to the discovery deactivation request, and may include a result of discovery deactivation and cause information. Meanwhile, when a discovery deactivation response message is received from the first D2D server 60, the second terminal 20 may transition to the idle state (S264). That is, the second terminal stops sending and receiving the discovery message.

After completing the deactivation procedure of the limited discovery service for the second terminal 20, the first D2D server 60 may release the radio resource allocated to the first terminal 10 for transmitting and receiving a discovery message. (S265, S266, S267, S268, S269). Here, the procedure for releasing radio resources allocated to the first terminal 10 may be the same as the procedure for releasing radio resources allocated to the second terminal 20 described above.

 When the release of the radio resource allocated to the first terminal 10 is completed, the first D2D server 60 responds to the discovery deactivation request message received from the first terminal 10 and the discovery deactivation response message (DEACTIVATE DISCOVERY) RSP) may be transmitted to the MME 40 (S270). The MME 40 may transmit a discovery disable response message to the first terminal 10 (S271). Thereafter, the first D2D server 60 may release the setting of the discovery ID assigned for the first terminal 10 (S272). Meanwhile, when a discovery deactivation response message is received from the first D2D server 60, the first terminal 10 may transition to the idle state (S273). That is, the first terminal stops sending and receiving the discovery message.

Limited discovery using user planes

Hereinafter, an operation procedure (enable / disable) for a limited discovery service using a user plane will be described. When a D2D discovery service is provided using a user plane, the DMF of the terminal operates in conjunction with a D2D server through an eNB, S-GW / P-GW, and uses the IP layer protocol. Here, a terminal to discover a specific terminal is defined as a first terminal (ie, a search terminal), and a discovery target terminal is defined as a second terminal (ie, a searched terminal). In addition, the procedure described below assumes that both the first terminal and the second terminal start in an idle state.

20 is a flowchart illustrating a procedure (S300 to S313) for activation of a limited discovery service using a user plane, and FIG. 21 is a flowchart illustrating a procedure (S314 to S326) for activating a limited discovery service using a user plane.

20 and 21, the procedure for activating the limited discovery service using the user plane is the same as the procedure for activating the limited discovery service using the control plane (see FIGS. 16 and 17) except for the following differences.

● Delivery of discovery protocol message between D2D server and D2D server

-Using function nodes included in the user plane

-Using IP packet-based discovery control messages

● Discovery feasibility estimation

-The D2D server receiving the discovery request message requests the MME, and the MME responds to the D2D server after performing the discovery probability estimation procedure in the form of limited discovery using the control plane.

22 is a flowchart illustrating a procedure for deactivating a limited discovery service using a user plane.

Referring to FIG. 22, a procedure for deactivating a limited discovery service using a user plane is the same as a procedure for deactivating a discovery service using a control plane (see FIGS. 18 and 19) except for the following differences.

● Delivery of discovery protocol message between D2D server and D2D server

-Using function nodes included in the user plane

-Using IP packet-based discovery control messages

Blind Limited Discovery Service

The blind discovery service refers to performing discovery on all terminals that mutually agree to discovery without specifying a specific terminal. The blind discovery procedure starts when an application requests blind discovery, and the blind discovery service can be performed for a period of time through an operation mode setting or the like, until a request to release the application is discovered.

The procedure for activating the blind discovery service is started when an application of the first terminal (that is, the discovery terminal) delivers a blind discovery request, that is, a discovery service request of terminals agreeing to mutual discovery with the DMF. The DMF receiving the blind discovery service may transmit a discovery activation request message including information such as discovery type and discovery status to the D2D server.

When a discovery activation request message is received from the first terminal, the D2D server may perform an authentication procedure of the first terminal requesting blind discovery, and then determine which of the target terminals to participate in discovery. That is, since the D2D server stores a list of terminal IDs that have agreed to discovery with the first terminal, a terminal having a possibility of being close to the first terminal can be detected using the terminal ID list. The D2D server checks the serving cell of the corresponding terminal when the terminal is in the RRC_CONNECTED state, and when the terminal is in the RRC_IDLE state, transitions the terminals located in the same tracking area among the corresponding terminals to the RRC_CONNECTED state and checks each serving cell of the terminal do. The D2D server may give the discovery ID to the first terminal as well as other terminals (second terminal to N-th terminal) that may be close to the first terminal.

After completing the above process, the D2D server may first perform a discovery transmission channel allocation procedure of the first terminal. Next, the D2D server may perform discovery channel allocation and discovery channel information delivery procedures of the first terminal for each of the second terminal to the Nth terminal in cooperation with the eNB and the LTE function (function +) of the corresponding terminal. The D2D server may activate transmission and reception of a discovery message after passing the discovery ID of the first terminal and the terminal ID of the first terminal to the DMF.

After completing the above process, the D2D server receives channel information of the second terminal to the N-th terminal from the LTE function (function +) of the first terminal or the discovery ID and terminal IDs of the second terminal to the N-th terminal. It can be transmitted to the DMF, it can activate the transmission and reception of discovery messages.

Upon completion of the process described above, the first to Nth terminals all transition to the 'searchable & searchable' state. Accordingly, the first terminal may attempt to receive a discovery message from the second terminal to the N-th terminal through a discovery channel for the second terminal to the N-th terminal which is already known, and if the discovery message is successfully received, the corresponding terminal The application can be notified that this has been found. Similarly, the second terminal to the N-th terminal may attempt to receive a discovery message from the first terminal through a discovery channel for a first terminal that is already known, and if the reception of the discovery message is successful, the application has been discovered. Can be notified.

The blind discovery service deactivation procedure may be initiated by the application. That is, when a blind discovery service stop request is received from an application, the DMF may transmit a discovery deactivation request message to the D2D server, and the received D2D server releases and stops discovery channel allocation for each of the first terminal to the Nth terminal Request to the corresponding eNB to perform necessary procedures with the corresponding terminal. The D2D server may request discovery deactivation from the DMFs of the second terminal to the N-th terminal, and may receive a response to discovery deactivation from the DMFs of the second terminal to the N-th terminal. Finally, the D2D server may transmit a response message for discovery deactivation to the DMF of the first terminal.

Report limited discovery events and discovery information

The limited discovery event and the discovery information reporting procedure refer to a procedure for reporting an event occurring when a D2D discovery procedure is performed and information obtained through the D2D discovery procedure to a D2D server. The discovery event report is a procedure in which a terminal transmitting a discovery message and a terminal receiving the discovery event transmit a corresponding event to a D2D server, and the discovery information reporting is a procedure in which information of the discovered proximity terminal is reported to the D2D server.

These information can be used to manage billing for D2D discovery and proximity of the terminal. The information obtained through the limited discovery event and the discovery information reporting procedure may be used as advance information for future direct communication and mode selection (direct communication or communication via a network entity).

The limited discovery event and the discovery information reporting procedure described above may take into account the form in which the discovery terminal and the searched terminal exist in the same operator network and in the different operator network. In particular, when the search terminal and the searched terminal exist in different operator networks, the above-described procedure may be performed through a linkage procedure between D2D servers.

23 is a flowchart illustrating a discovery event using a control plane and a procedure for reporting discovered information.

Referring to FIG. 23, the first terminal 10 may transmit a discovery event report message (DISCOVERY_EVENT_REPORT) to the MME 40 (S400). The MME 40 may transmit the discovery event report message received from the terminal to the first D2D server 60 (S401). The discovery event report message may include an event type, searched terminal ID information, and the like.

The first D2D server 60 may update the discovered information based on the received discovery event report message (S402), and may access a charging function to manage charging for the discovery (S403).

24 is a flowchart illustrating a discovery event using a user plane and a procedure for reporting discovered information.

Referring to FIG. 24, the first terminal 10 may transmit a discovery event report message (DISCOVERY_EVENT_REPORT) to the first D2D server 60 (S410). The discovery event report message may include an event type, searched terminal ID information, and the like.

The first D2D server 60 may update the discovered information based on the received discovery event report message (S411), and may access a charging function to manage charging for the discovery (S412).

Discovery related information exchange between D2D servers

The D2D discovery configuration information exchange procedure between D2D servers is an information exchange procedure that enables discovery procedures between terminals managed by different D2D servers. In particular, through this procedure, a discovery procedure between terminals joined to different operators is possible. This procedure includes the procedure of transmitting spectrum information and radio resource allocation information for limited discovery managed by the D2D server of each operator, and the procedure of transmitting the protocol message for limited discovery described above transparently. . Information and procedures exchanged between D2D servers for open discovery are as follows.

● Spectrum & Wireless Resource Setting Information

-Spectrum-related information for limited discovery, and discovery resource configuration information of a cell managed by a D2D server is transmitted to a counterpart D2D server

● Application authorization process

-Encapsulate the protocol message for the application authentication procedure described in 'Limited Discovery Application Authentication' and exchange it with the counterpart D2D server

● Discovery consent and disagreement

-Encapsulate and exchange the protocol message for the procedure for securing the searchable terminal list described in 'Limited Discovery Agreement and Release Agreement' with the counterpart D2D server

● Discovery ID acquisition process

-Encapsulate the protocol message for securing the discovery ID of the terminal to be searched described in the 'limited discovery service for a specific terminal' and exchange it with a counterpart D2D server

● Discovery Activation Procedure

-Encapsulating and exchanging protocol messages for the limited discovery activation procedure described in the 'Limited Discovery Service for Specific Terminals' and 'Blind Limited Discovery Service' exchanges with other D2D servers

● Discovery deactivation procedure

-Encapsulate and exchange protocol messages for the limited discovery deactivation procedure described in 'Limited Discovery Service for a Specific Terminal' and 'Blind Limited Discovery Service'

● Discovery information reporting procedure

-Encapsulating and exchanging protocol messages for the limited discovery reporting procedure described in 'Restricted Discovery Event and Discovery Information Reporting' above

25 is a flowchart illustrating discovery setting information exchange procedures (S500 to S514) between D2D servers for limited discovery using a control plane function, and FIG. 26 illustrates discovery setup between D2D servers for limited discovery using a control plane function It is a flow showing the information exchange procedure (S515 ~ S533).

25 and 26, in the wireless configuration exchange procedure, the first D2D server 60 may transmit a resource configuration information request message (RESOURCE_CONFIG_INFO_REQ) to the eNB / MME 50 (S500). The eNB / MME 50 may transmit the resource configuration information response message (RESOURCE_CONFIG_INFO_RSP) to the first D2D server 60 in response to the resource configuration information request message (S501). The resource configuration information request message may include cell ID information, and the resource configuration information response message may include radio resource configuration information. The first D2D server 60 may transmit a discovery information message (DISCOVERY_INFO_XFER) to the second D2D server 70 (S502). The discovery information message may include radio resource configuration information.

In the application approval procedure, the first D2D server 60 may transmit the application discovery feature request message (APP_DISCOVERY_FEATURE_REQ) to the second D2D server 70 (S503). The second D2D server 70 may transmit the application discovery feature response message (APP_DISCOVERY_FEATURE_RSP) to the first D2D server 60 in response to the application discovery feature request message (S504). The application discovery feature request message means a message for requesting discovery discovery authentication of an application, and may include application ID, terminal ID information, and the like. The application discovery feature response message means a response message to an application's discovery use authentication request, and may include a result, cause information, and the like.

In the discovery consent procedure, the first D2D server 60 may transmit an invitation request message (INVITE_REQ) to the second D2D server 70 (S505). The second D2D server 70 can transmit the invitation request message received from the first D2D server 10 to the eNB / MME 50 (S506), and the eNB / MME 50 is the second D2D server 70 The invitation request message received from can be transmitted to the first terminal 10 (S507). The first terminal 10 may transmit an invitation response message (INVITE_RSP) to the eNB / MME 50 in response to the invitation request message (S508), and the eNB / MME 50 transmits the invitation response message to the second D2D server It can be transmitted to (70) (S509).

Thereafter, the second D2D server 70 may transmit the invitation response message to the first D2D server 60 in response to the invitation request message received from the first D2D server 60 (S510). The first D2D server 60 may transmit the invitation completion message (INVITE_COMPLETE) to the second D2D server 70 in response to the invitation response message (S511). The second D2D server 70 may transmit the invitation completion message to the first terminal 10 (S512).

Here, the invitation request message means a request message used for adding a searched terminal list, and may include a target terminal ID and application ID information. The invitation response message means a response message used for adding a searched terminal list, and may include results, cause information, and the like. The invitation completion message means a completion message used for adding a searched terminal list, and may include discovery ID information of a source terminal.

In the discovery ID acquisition procedure, the first D2D server 60 may transmit a discovery ID request message (DISCOVERY_ID_REQ) to the second D2D server 70 (S513), and the second D2D server 70 to the discovery ID request message In response, the discovery ID response message may be transmitted to the first D2D server 60 (S514).

Here, the discovery ID request message means a message for requesting a discovery ID for a specific terminal, and may include terminal ID information. The discovery ID response message means a response message to a discovery ID request of a specific terminal, and may include a result, a cause, and discovery ID information.

In the activation discovery request procedure, the first D2D server 60 may transmit a discovery activation request message (REQUEST_DISCOVERY_ACTIVATION) to the second D2D server 70 (S515). The second D2D server 70 can transmit a discovery activation request message received from the first D2D server 60 to the eNB / MME 50 (S516), and the eNB / MME 50 is the second D2D server 70 ) May transmit a discovery activation request message received from the first terminal 10 (S517). The first terminal 10 may transmit an activation discovery request message (ACTIVATE_DISCOVERY_REQ) to the eNB / MME 50 in response to the discovery activation request message (S518), and the eNB / MME 50 may receive the first terminal 10 The activation discovery request message received from can be transmitted to the second D2D server 70 (S519).

Thereafter, the second D2D server 70 may transmit an activation discovery request message to the first D2D server 60 (S520), and the first D2D server 60 responds to the activation discovery request in response to the activation discovery request message A message (ACTIVATE_DISCOVERY_RSP) may be transmitted to the second D2D server 70 (S521). When the activation discovery response message is received from the first D2D server 60, the second D2D server 70 may transmit the activation discovery response message to the eNB / MME 50 (S522). The eNB / MME 50 may transmit the activation discovery response message received from the second D2D server 70 to the first terminal 10 (S523).

Here, the discovery activation request message means a discovery activation request message starting from a network, and may include a cause, discovery type, discovery status, range class (for a discovery terminal), and reception mode (for a discovery terminal) information. . The activation discovery request message refers to a message requesting activation of D2D discovery, and may include a discovery type, discovery status, target terminal ID, permission flag, reception mode, range class information, and the like. The activation discovery response message means a response message to a D2D discovery activation request, and may include a result, a cause, and target discovery ID information.

In the deactivation discovery request procedure, the first D2D server 60 may transmit a discovery deactivation request message (REQUEST_DISCOVERY_DEACTIVATION) to the second D2D server 70 (S524). The second D2D server 70 can transmit a discovery deactivation request message received from the first D2D server 60 to the eNB / MME 50 (S525), and the eNB / MME 50 is the second D2D server 70 ), The discovery deactivation request message may be transmitted to the first terminal 10 (S526). The first terminal 10 may transmit the deactivation discovery request message (DEACTIVATE_DISCOVERY_REQ) to the eNB / MME 50 in response to the discovery deactivation request message (S527), and the eNB / MME 50 may be the first terminal 10 The deactivation discovery request message received from may be transmitted to the second D2D server 70 (S528).

Thereafter, the second D2D server 70 may transmit an inactive discovery request message to the first D2D server 60 (S529), and the first D2D server 60 responds to the inactive discovery request in response to the inactive discovery request message A message (DEACTIVATE_DISCOVERY_RSP) may be transmitted to the second D2D server 70 (S530). When the inactive discovery response message is received from the first D2D server 60, the second D2D server 70 may transmit the inactive discovery response message to the eNB / MME 50 (S531). The eNB / MME 50 may transmit the deactivated discovery response message received from the second D2D server 70 to the first terminal 10 (S532).

Here, the discovery deactivation request message means a message requesting deactivation of D2D discovery starting from a network, and may include cause information. The deactivated discovery request message means a message requesting deactivation of D2D discovery. The deactivation discovery response message means a response message to the D2D discovery deactivation request, and may include a result, cause information, and the like.

In the discovery information reporting procedure, the first D2D server 60 may transmit a discovery event reporting message (DISCOVERY_EVENT_REPORT) to the second D2D server 70 (S533). Here, the discovery event report message means a D2D discovery related event and information report message, and may include an event type, discovered terminal ID information, and the like.

27 is a flowchart illustrating discovery setting information exchange procedures (S600 to S610) between D2D servers for limited discovery using a user plane function, and FIG. 28 is a discovery setup between D2D servers for limited discovery using a user plane function It is a flow showing the information exchange procedure (S611 ~ S623).

27 and 28, a radio setting exchange procedure, an application approval procedure, a discovery ID acquisition procedure, and a discovery information reporting procedure are the same as the procedures illustrated in FIGS. 25 and 26 above.

The discovery consent procedure, the activation discovery request procedure, and the deactivation discovery request procedure are shown in FIG. 25 except that a message transmitted between the first terminal 10 and the second D2D server 70 does not pass through the eNB / MME 50. And the procedure shown in FIG. 26.

Organize information for D2D discovery

D2D discovery information for limited discovery refers to information transmitted and received when performing a limited discovery procedure. D2D discovery information for limited discovery may include a discovery ID that can indicate a specific terminal (ie, UE), and these information should be arbitrary information that is not a security problem even when exposed. In addition, when the terminal has mapping information between the received discovery information and the terminal ID, the terminal should be able to recognize a specific terminal subscribed to its own operator network or another operator network by using the mapping information, and the recognized terminal ID It should be able to connect to a specific terminal by using.

D2D discovery information is allocated by the DME existing in the network, and the information can be obtained through the opening of the terminal as described above.

The D2D discovery message for limited discovery may include a separator, discovery ID and application ID. The separator may indicate the type of D2D discovery information. The discovery ID is information for recognizing a terminal that has transmitted D2D discovery information, and it has a 1: 1 mapping relationship with the terminal ID. The application ID may be used for delivering an application ID requesting the discovery service. If the discovery message for limited discovery and the discovery message for open discovery have different lengths, the reserved field of the limited discovery message is not used.

The delimiter included in the D2D discovery message for limited discovery may have a length of 2 bits, which can be defined as follows.

● 00

  -Limited D2D discovery information

● 01

  -Open D2D Discovery Information

● 10

  -Public safety information

● 11

  -Spare field

The discovery ID included in the limited D2D discovery message may be used to obtain the ID of the corresponding terminal. When the terminal receives the discovery message, it can recognize the terminal and obtain the terminal ID by comparing the discovery ID included in the discovery message with the list of searched terminals stored therein.

The discovery ID may be defined as a globally unique ID or a locally unique ID. Each case has the following characteristics.

● Globally unique ID

-Since it is unique globally, there is no need to change the ID even if the terminal moves through the region

● Locally unique ID

  -ID change is required when the device to be searched leaves the designated area

  -Information needs to be changed whenever the discovery ID of the terminal included in the searched terminal list is changed

29 is a conceptual diagram illustrating an embodiment (globally unique discovery ID) of a discovery message configuration for limited discovery.

Referring to FIG. 29, the device discovery message has a size of 16 bytes, and may include discovery type information, discovery ID, and application ID. The discovery type information may have a size of 2 bits. The discovery ID may have a size of 64 bits, and similar to the configuration of the international mobile subscriber identity (IMSI) used in the existing LTE, the mobile country code (MCC), mobile network code (MNC) And a mobile ID (mobile identifier). The application ID may have a size of 62 bits.

30 is a conceptual diagram illustrating another embodiment (locally unique discovery ID) of a discovery message configuration for limited discovery.

Referring to FIG. 30, the device discovery message has a size of 16 bytes in total, and may include discovery type information, discovery ID, and application ID. The discovery type information may have a size of 2 bits. The discovery ID may have a size of 56 bits or 68 bits, and may have a configuration similar to a globally unique temporary UE identity (GUTI) used in the existing LTE. That is, the discovery ID is hierarchical including a mobile country code (MCC), a mobile network code (MNC), an MME group ID, an MME code, and an MME temporary mobile subscriber identity (M-TMSI) (or temporary ID). It may be configured in a form, or may be configured in a hierarchical form including an MME group ID, an MME code, and an M-TMSI (or temporary ID). The application ID may have a size of 70 bits or 58 bits.

31 is a conceptual diagram illustrating the definition of a protocol message for D2D discovery, and FIG. 32 is a conceptual diagram illustrating the definition of another protocol message for D2D discovery. 31 and 32, the protocol message means the protocol message shown in FIGS. 12 to 28.

33 is a conceptual diagram illustrating parameter definition of a protocol message for D2D discovery. Referring to FIG. 33, a definition of parameters of a protocol message can be seen.

Although described with reference to the above embodiments, those skilled in the art understand that various modifications and changes can be made to the present invention without departing from the spirit and scope of the present invention as set forth in the claims below. Will be able to.

10: first terminal
20: second terminal
30: eNB
40: MME
50: eNB / MME
60: first D2D server
70: second D2D server

Claims (11)

In a discovery (restricted discovery) activation method performed in the discovery (discovery) terminal,
Transmitting a limited discovery activation request message to activate a limited discovery of a discovery terminal to a device-to-device communication (D2D) server;
Receiving the radio resource information used for limited discovery through a base station linked with the D2D server when activation of the limited discovery is accepted by the searched terminal;
Receiving a limited discovery activation response message that is a response to the limited discovery activation request message from the D2D server; And
And performing limited discovery with the discovery terminal that has accepted the activation of the limited discovery through the radio resource indicated by the radio resource information, and the radio resource information is the discovery that has accepted activation of the limited discovery. A limited discovery activation method determined based on a channel condition measured at the terminal. The method according to claim 1,
The limited discovery activation request message includes a discovery type (discovery type), a discovery status, an application identifier (ID) of the discovery terminal and a discovery terminal ID. The method according to claim 1,
The limited discovery activation response message includes a discovery ID of the discovery terminal and a discovery ID of the discovery terminal. The method according to claim 1,
When the limited discovery activation response message is received, the discovery terminal transitions to the limited discovery activation state. The method according to claim 1,
The radio resource is a limited discovery activation method, characterized in that when the limited discovery activation is accepted by the searched terminal, it is assigned to the searched terminal. The method according to claim 5,
When the radio resource is allocated to the searched terminal, the discovery activation method of the discovery terminal and the discovery ID of the searched terminal is set. The method according to claim 1,
The discovery activation method characterized in that the message transmitted between the discovery terminal and the D2D server is transmitted through a mobile management entity (MME). In a discovery (restricted discovery) deactivation method performed in the discovery (discovery) terminal,
Transmitting a limited discovery disable request message for deactivating limited discovery of a discovery terminal that has accepted limited discovery to a device-to-device communication (D2D) server;
Receiving a message instructing to release a radio resource allocated for limited discovery from a base station associated with the D2D server when limited discovery of the searched terminal is deactivated;
Receiving a limited discovery deactivation response message instructing deactivation of the limited discovery that is a response to the limited discovery deactivation request message from the D2D server; And
And when the resource release operation based on the limited discovery deactivation response message is completed, transitioning to an idle state. The method according to claim 8,
When the limited discovery deactivation request message is received, the limited discovery deactivation method characterized in that radio resources allocated to the searched terminal are released. The method according to claim 9,
When the radio resource allocated to the terminal to be searched is released, the discovery discovery set up method for the searched terminal is released. The method according to claim 8,
When the radio resource allocated to the discovery terminal is released, the discovery discovery inactive method set for the discovery terminal is released.

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