KR20200115155A - Method and apparatus for enabling connectivity for edge computing service to device - Google Patents

Abstract

The present disclosure relates to a 5^th generation (5G) or pre-5G communication system to support a higher data transmission rate than that of 4^th generation (4G) communication system such as a long term evolution (LTE). The present disclosure can be applied to an intelligent service (for example, smart home, smart building, smart city, smart car or connected car, healthcare, digital education, retail business, security and safety related services, etc.) based on a 5G communication technology and an IoT-related technology. According to various embodiments of the present invention, provided is a method of providing information on a DNS server or an edge computing service configuration server to a terminal to support an operation of discovering an edge server by the terminal. A communication method of a terminal in a wireless communication system comprises the steps of: transmitting a first message including information requesting use of an edge computing service to a session management function (SMF); and receiving, from the SMF, a second message including information on a configuration server for receiving configuration information for the edge computing service.

Description

Method and apparatus for providing connectivity to a terminal in order to use edge computing service {METHOD AND APPARATUS FOR ENABLING CONNECTIVITY FOR EDGE COMPUTING SERVICE TO DEVICE}

The present invention relates to a communication system, and relates to a method for providing information on a DNS server or edge computing service configuration server to a terminal to support an operation of discovering an edge server by a terminal.

Efforts have been made to develop an improved 5G (5th generation) communication system or a pre-5G communication system in order to meet the increasing demand for wireless data traffic after the commercialization of 4G (4th generation) communication systems. For this reason, the 5G communication system or the pre-5G communication system is called a Beyond 4G Network communication system or a Long Term Evolution (LTE) system (Post LTE) system.

In order to achieve a high data rate, the 5G communication system is being considered for implementation in the ultra-high frequency (mmWave) band (for example, the 60 gigabyte (60 GHz) band). In order to mitigate the path loss of radio waves in the ultra-high frequency band and increase the transmission distance of radio waves, in 5G communication systems, beamforming, massive MIMO, and Full Dimensional MIMO (FD-MIMO) ), array antenna, analog beam-forming, and large scale antenna technologies are being discussed.

In addition, in order to improve the network of the system, in 5G communication system, advanced small cell, advanced small cell, cloud radio access network (cloud RAN), ultra-dense network , Device to Device communication (D2D), wireless backhaul, moving network, cooperative communication, CoMP (Coordinated Multi-Points), and interference cancellation And other technologies are being developed.

In addition, in the 5G system, the advanced coding modulation (Advanced Coding Modulation, ACM) method of FQAM (Hybrid Frequency Shift Keying and Quadrature Amplitude Modulation) and SWSC (Sliding Window Superposition Coding), and advanced access technology, FBMC (Filter Bank Multi Carrier) ), NOMA (Non Orthogonal Multiple Access), and SCMA (Sparse Code Multiple Access) are being developed.

The 5G system is considering supporting various services compared to the existing 4G system. For example, the most representative services are mobile ultra-wide band communication service (eMBB: enhanced mobile broad band), ultra-reliable and low latency communication service (URLLC: ultra-reliable and low latency communication), and large-scale device-to-device communication service (mMTC: massive machine type communication), evolved multimedia broadcast/multicast service (eMBMS), and the like. In addition, a system that provides the URLLC service may be referred to as a URLLC system, and a system that provides an eMBB service may be referred to as an eMBB system. In addition, the terms service and system may be used interchangeably.

Among them, the URLLC service is a service newly considered in the 5G system, unlike the existing 4G system, and has ultra-high reliability (for example, a packet error rate of about 10 ^-5 ) and low latency (for example, About 0.5msec). In order to satisfy such strict requirements, the URLLC service may need to apply a transmission time interval (TTI) shorter than that of the eMBB service, and various operation methods utilizing this may be considered.

Meanwhile, the Internet is evolving from a human-centered connection network in which humans create and consume information, to an Internet of Things (IoT) network that exchanges and processes information between distributed components such as objects. Internet of Everything (IoE) technology, which combines IoT technology with big data processing technology through connection with cloud servers, is also emerging. In order to implement IoT, technology elements such as sensing technology, wired/wireless communication and network infrastructure, service interface technology, and security technology are required, and recently, a sensor network for connection between objects, machine to machine , M2M), and MTC (Machine Type Communication) technologies are being studied.

In the IoT environment, intelligent IT (Internet Technology) services that create new value in human life by collecting and analyzing data generated from connected objects can be provided. IoT is the field of smart home, smart building, smart city, smart car or connected car, smart grid, healthcare, smart home appliance, advanced medical service, etc. through the convergence and combination of existing IT (information technology) technology and various industries. Can be applied to.

Accordingly, various attempts have been made to apply a 5G communication system to an IoT network. For example, technologies such as sensor network, machine to machine (M2M), and MTC (Machine Type Communication) are implemented by techniques such as beamforming, MIMO, and array antenna, which are 5G communication technologies. will be. As the big data processing technology described above, a cloud radio access network (cloud RAN) is applied as an example of the convergence of 5G technology and IoT technology.

The terminal must access the edge server to use edge computing service. However, edge servers may be arranged for each region, so the terminal needs to know which edge server to access in that region. For this, the terminal must be able to access a DNS server or a configuration server operated by a provider providing edge computing services. After that, the terminal obtains the address of the edge server to which it is connected from the server, accesses the edge server, and can use edge computing services. Accordingly, the present invention proposes a method of providing the terminal with server information that can inform the terminal to which edge server to access.

The technical problems to be achieved in the present invention are not limited to the technical problems mentioned above, and other technical problems that are not mentioned will be clearly understood by those of ordinary skill in the technical field to which the present invention belongs from the following description. I will be able to.

In order to solve the above problems, a communication method of a terminal according to an embodiment of the present invention includes: transmitting a first message including information requesting use of an edge computing service to a session management function (SMF); And receiving, from the SMF, a second message including information on a configuration server for receiving configuration information for the edge computing service, wherein the information on the configuration server requests use of the edge computing service. It may be set by a policy and charging function (PCF) based on the information.

In addition, the first message may be a PDU session establishment message or a PDU session modification request message.

In addition, information on the configuration server may be received through protocol configuration options (PCO).

In addition, the information on the setting server may include information on the setting server determined based on at least one of information on the location of the terminal and information on the load of the setting servers.

In addition, the SMF communication method according to an embodiment of the present invention for solving the above problems includes: receiving a first message from the terminal including information requesting the use of the edge computing service of the terminal; Transmitting a second message for policy setting including information for requesting use of the edge computing service to a policy and charging function (PCF); Receiving, from the PCF, a third message including information on a setting server for receiving setting information for the edge computing service set based on information requesting the use of the edge computing service; And transmitting a fourth message including information on the setting server to the terminal.

In addition, the fourth message may include protocol configuration options (PCO) including information on the configuration server.

In addition, the terminal according to an embodiment of the present invention for solving the above problems, the transceiver; And a second message including information on a configuration server for transmitting a first message including information for requesting use of edge computing service to a session management function (SMF), and receiving configuration information for the edge computing service. Including a control unit for receiving from the SMF, the information on the setting server may be set by a policy and charging function (PCF) based on information requesting the use of the edge computing service.

In addition, the SMF according to an embodiment of the present invention for solving the above problems includes: a transceiver; And a first message including information for requesting use of the edge computing service of the terminal is received from the terminal, and a second message for policy setting including information for requesting use of the edge computing service is sent to a PCF (policy and charging function), and receiving from the PCF a third message including information on a setting server for receiving setting information for the edge computing service set based on information requesting the use of the edge computing service, and And a controller for transmitting a fourth message including information on the setting server to the terminal.

According to an embodiment of the present invention, a terminal may obtain information on a server capable of receiving information on a server capable of receiving the edge computing service by accessing it for the first time. Therefore, the terminal communicates with the server to find an edge server to which it is connected, and can use edge computing services through the edge server. In addition, since the terminal can receive it through the connection of the mobile communication system, the corresponding information can be received without an additional application layer operation. That is, the information of the server may be obtained through basic operations such as establishing a data connection to the mobile communication system or exchanging policy information by accessing the mobile communication system. In addition, mobile communication service providers can provide the information only to terminals that are licensed to use edge computing services. In addition, according to the function of determining the location of the terminal, which is a basic function of the mobile communication system, the terminal can receive information of a server suitable for the current location of the terminal. Alternatively, the terminal may receive information on the server according to the PLMN to which the terminal should access.

The effects obtainable in the present invention are not limited to the above-mentioned effects, and other effects not mentioned can be clearly understood by those of ordinary skill in the technical field to which the present disclosure belongs from the following description. will be.

1 shows a system architecture for providing edge computing service and a system architecture for a 5G mobile communication system according to an embodiment of the present invention, and a relationship thereof.
FIG. 2 shows a structure of an enabling layer for enabling an application and edge computing service in a terminal, and a communication layer for accessing a mobile communication system according to an embodiment of the present invention. It also shows the structure of the edge application server in the edge server that provides edge computing service, the enabling function to enable edge computing service, and the platform or orchestration function for edge computing system.
3 shows a procedure for establishing a data connection by a terminal accessing a 5G mobile communication system according to an embodiment of the present invention. Through this procedure, the terminal can receive information on the server to which it should initially access.
4 shows a procedure for registering a terminal in a 5G mobile communication system according to an embodiment of the present invention. Through this procedure, the terminal can receive the policy including the information of the server to be initially accessed.
FIG. 5 illustrates a method of using a PDU Session Modification procedure to update information on a server to which a terminal should initially access for an Edge Computing service to a terminal according to a change in mobility of a terminal or information in a network according to an embodiment of the present invention. Show.
6 is a method of using a procedure of updating a policy to update information of a server to which a terminal should initially access for an edge computing service to a terminal according to a change in mobility of a terminal or information in a network according to an embodiment of the present invention Represents.
7 is a block diagram of a terminal according to an embodiment of the present invention.
8 is a block diagram of a network entity according to an embodiment of the present invention.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. In this case, it should be noted that in the accompanying drawings, the same components are indicated by the same reference numerals as possible. In addition, detailed descriptions of known functions and configurations that may obscure the subject matter of the present invention will be omitted.

In describing the embodiments herein, descriptions of technical contents that are well known in the technical field to which the present invention pertains and are not directly related to the present invention will be omitted. This is to more clearly convey the gist of the present invention by omitting unnecessary description.

For the same reason, some components in the accompanying drawings are exaggerated, omitted, or schematically illustrated. In addition, the size of each component does not fully reflect the actual size. The same reference numerals are assigned to the same or corresponding components in each drawing.

Advantages and features of the present invention, and a method of achieving them will become apparent with reference to the embodiments described below in detail together with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, but may be implemented in a variety of different forms, only the present embodiments are intended to complete the disclosure of the present invention, and the general knowledge in the technical field to which the present invention pertains. It is provided to completely inform the scope of the invention to those who have it, and the invention is only defined by the scope of the claims. The same reference numerals refer to the same components throughout the specification.

At this time, it will be appreciated that each block of the flowchart diagrams and combinations of the flowchart diagrams may be executed by computer program instructions. Since these computer program instructions can be mounted on the processor of a general purpose computer, special purpose computer or other programmable data processing equipment, the instructions executed by the processor of the computer or other programmable data processing equipment are described in the flowchart block(s). It creates a means to perform functions. These computer program instructions can also be stored in computer-usable or computer-readable memory that can be directed to a computer or other programmable data processing equipment to implement a function in a particular way, so that the computer-usable or computer-readable memory It is also possible to produce an article of manufacture containing instruction means for performing the functions described in the flowchart block(s). Computer program instructions can also be mounted on a computer or other programmable data processing equipment, so that a series of operating steps are performed on a computer or other programmable data processing equipment to create a computer-executable process to create a computer or other programmable data processing equipment. It is also possible for instructions to perform processing equipment to provide steps for executing the functions described in the flowchart block(s).

In addition, each block may represent a module, segment, or part of code that contains one or more executable instructions for executing the specified logical function(s). In addition, it should be noted that in some alternative execution examples, functions mentioned in blocks may occur out of order. For example, two blocks shown in succession may in fact be executed substantially simultaneously, or the blocks may sometimes be executed in reverse order depending on the corresponding function.

In this case, the term'~ unit' used in the present embodiment means software or hardware components such as FPGA or ASIC, and'~ unit' performs certain roles. However,'~ part' is not limited to software or hardware. The'~ unit' may be configured to be in an addressable storage medium, or may be configured to reproduce one or more processors. Thus, as an example,'~ unit' refers to components such as software components, object-oriented software components, class components and task components, processes, functions, properties, and procedures. , Subroutines, segments of program code, drivers, firmware, microcode, circuitry, data, database, data structures, tables, arrays, and variables. The components and functions provided in the'~ units' may be combined into a smaller number of elements and'~ units', or may be further divided into additional elements and'~ units'. In addition, components and'~ units' may be implemented to play one or more CPUs in a device or a security multimedia card.

Meanwhile, the architecture for implementing edge computing services in 3GPP next-generation communication systems is being discussed continuously. The edge computing technology may be referred to as mobile edge computing, or multi-access edge computing, and will be referred to as MEC for convenience in the present invention. MEC installs a wireless base station or a gateway (or UPF) close to the wireless base station, and deploys various services and caching contents close to the user terminal by applying distributed cloud computing technology on it to alleviate the congestion of the mobile core network and It is a technology that achieves low-latency communication in data communication and creates new services based on this. The MEC system provides application developers and content providers with cloud computing capabilities and IT service environments at the edge of the mobile network. In particular, it provides ultra-low-latency and large-capacity bandwidth to application applications and enables access to real-time network information. Therefore, application applications that provide MEC services can provide services to terminals through 5G system. In addition, the 5G system can provide a function for a terminal using the MEC service to access the MEC system. Not only 5G system, but also 4G system can provide functions for MEC service.

For convenience of description below, some terms and names defined in the 3rd generation partnership project long term evolution (3GPP) standard may be used. However, the present invention is not limited by the terms and names, and can be applied equally to systems conforming to other standards.

1 shows the structure of a MEC system and a 5G mobile communication system according to an embodiment of the present invention, and a relationship between the two.

A description of network entities or network nodes appearing in FIG. 1 is as follows.

The 5G core network 110 may be formed of the following network functions. The access and mobility management function (AMF) 112 is a network function that manages mobility of the terminal 120. The session management function (SMF) 113 is a network function that manages connection to a packet data network provided to the terminal 120. This connection is called a PDU (protocol data unit) session. The PCF (policy and charging function) 114 is a network function for applying a service policy of a mobile communication service provider, a charging policy, and a policy for a PDU session to the terminal 120. UDM (not shown) stands for unified data management, and is a network function that stores information on subscribers. The network exposure function (NEF) 115 can access information for managing the terminal 120 in a 5G network, and thus subscribe to the mobility management event of the terminal 120 and the session management event of the terminal 120. Subscription, a request for session-related information, setting of charging information of the corresponding terminal 120, a request to change a PDU session policy for the corresponding terminal 120, and small data transmission for the corresponding terminal 120 may be performed. The 5G-RAN 111 refers to a base station that provides a wireless communication function to the terminal 120. UPF 116 is an abbreviation of the user plane function, and serves as a gateway for transmitting packets transmitted and received by the terminal 120. The UPF 116 may be located near the edge server 151 to support MEC, and accordingly, the data packet can be directly transferred to the edge network 130 to achieve low-latency transmission. The UPF 116 may also be connected to a data network 140 connected to the internet, and data to be transmitted to the internet among packets sent from the terminal 120 may be routed to the internet data network 140.

The MEC system structure 150 may be composed of a terminal 120, an edge server 151, and a configuration server 153. The terminal 120 supporting the MEC system 150 includes the MEC enabling layer 220 in the terminal 120, and a detailed structure will be described in FIG. 2. The edge server 151 refers to a server to which the terminal 120 accesses to use the MEC service, and a third party application application server is driven by the edge server 151. The detailed structure will be described in FIG. 2. And, to indicate the edge server 151, terms such as edge computing server, MEC server, MEC server, multi-access edge host, edge computing platform, MEC cloudlets, and edge hosting environment may be used interchangeably, but are limited thereto. It does not become. The configuration server 153 performs a function of transmitting configuration information for using the MEC service to the terminal 120. The configuration server 153 knows the deployment of edge servers 151 for each location. Before using the MEC service, the terminal 120 may access the configuration server 153 and receive configuration information necessary for using the MEC service (eg, edge server information to be accessed at a specific location). In addition, the configuration server 153 may be referred to as an edge enabling configuration function, edge data network configuration server, and the like, and is not limited to the terms, and provides configuration information for the terminal 120 to use the MEC service. If it refers to a connection server that can be received, it may correspond to this.

In addition, there may be a DNS server 154 for MEC service. The DNS server 154 may be used to resolve the IP address of the edge server 151 or to resolve the IP address of an application application server running on the edge server 151. That is, the DNS server 154 may be a network function that knows information about the edge server 151 or information about an application application server running on the edge server. The DNS server 154 may exist for each edge network covering a specific area, or one may exist in the entire MEC system. When the DNS server 154 for MEC exists in each edge network covering a specific area, the terminal 120 must know the information of the DNS server 154 for the corresponding location, and this may operate according to an embodiment of the present invention. . When there is one DNS server 154 for MEC in the entire MEC system, this DNS server 154 must know information about edge server information installed in the entire network and application application servers that can be provided by the MEC system. , This information may be provided to the DNS server 154 by the orchestration system.

The terminal 120 may access the 5G system 110 through the 5G base station 111 and establish a data connection. The 5G system 110 can allocate a UPF 116 that can access the edge network 150 in order to provide the MEC service to the terminal 120, and through the UPF 116, the terminal 120 It communicates with the edge server 151 and may communicate with a third party application server running in the edge server 151. The edge server 151 may negotiate with the PCF 114 or NEF 115 of the 3GPP network. Through this negotiation, the edge server 151 provides information necessary for the terminal 120 to use the MEC service to the 5G mobile communication system 110 through the PCF 114 or NEF 115, or the edge server 151 May use the exposure function (eg, location reporting of the terminal 120, session-related event reporting of the terminal 120, etc.) provided by the NEF 115 of the 5G mobile communication system to an external server.

FIG. 2 shows a structure of an enabling layer enabling an application and MEC service in a terminal, and a communication layer accessing a mobile communication system according to an embodiment of the present invention. In addition, FIG. 2 also shows the structure of an edge application server in an edge server that provides edge computing service, an enabling function that enables edge computing service, and a platform or orchestration function for an edge computing system.

Referring to FIG. 2, the application 210 of the terminal 120 refers to an application provided by a third party. That is, the application 210 refers to a client application program running in the terminal 120 for a specific application service. In addition, the application 210 may be referred to as a term such as client apps (Application), UE application, application client, etc., and is not limited to the term, but refers to a client application running in the terminal 120 This may be the case. Several applications 210 may be driven in the terminal 120. At least one or more of these applications 210 may use MEC services. The enabling layer 220 in the terminal 120 refers to a layer that performs an operation in the terminal 120 that enables the MEC service to be used. And, the enabling layer 220 is a term such as enabler client, MEC enabling layer, MEL (MEC enabling layer), enablement layer, MEC layer, multi-access edge enabling layer, UE enabling client, edge enabler client, etc. It may be called, and is not limited to the term, and a layer/client performing an operation within the terminal 120 that enables the MEC service to be used within the terminal 120 may correspond to this. The enabling layer 220 determines which application application 210 can use the MEC service, and connects the network interface so that data of the terminal client application can be transmitted to the application application server providing the MEC service. can do. In addition, the enabling layer 220 may perform an operation for establishing a data connection for using the MEC service with the 3GPP communication layer. 3GPP communication layer (3GPP Comm. layer) 230 refers to a layer that performs modem operation for using a mobile communication system, establishes a wireless connection for data communication, and registers the terminal 120 in the mobile communication system And, it establishes a connection for data transmission to a mobile communication system, and performs a role of transmitting and receiving data.

2 is an edge application server (Edge App 1, Edge App 2, Edge App 3) 250, which means an application server provided by a third party in the edge server 151 providing MEC service, and the corresponding edge application server It shows the structure of the enabling function (260) that enables MEC service to (250) and the platform or orchestration function (platform (orchestration) function) (270) for edge computing systems. The edge application server 250 is an application application server provided by a third party, and refers to a server that a third party client application application of the terminal 120 accesses and uses a service. In addition, the edge application server 250 may be referred to as a MEC app, a multi-access edge application, an edge application server, an edge application, etc., and is not limited to the term, but a third If it means an application application server provided by the self, it may correspond to this. The enabling function 260 can perform a function of managing information on the edge application servers 250, and which edge application is currently running in the edge network, and to send data to the edge application server 250 It manages what a required fully qualified domain name (FQDN) or internet protocol (IP) address is and informs the enabling layer 220 of the terminal 120 to perform a role. In addition, the enabling function 260 provides the edge application server 250 with an exposure function provided by the 3GPP network 110, that is, the NEF 115 of the 5G mobile communication system (mobility related event of the terminal 120, session related event, terminal (120) traffic route change event) can be used as a proxy. That is, in response to the request of the edge application server 250, the enabling function 260 may call the exposure service provided by the NEF 115 of the 5G mobile communication system, so that a necessary network exposure function can be used. In addition, the enabling function 260 may be referred to as a MEC enabling layer, an edge enabling server function, a MEC enabling layer server, a multi-access enabling layer, an edge enabler server, and the like, and is not limited to that term, but an edge application If it means a function that performs a function that enables the MEC service to the server 250, this may correspond. The platform functionality 270 refers to a platform function of a system to which the edge servers 151 constituting the edge network 150 are connected, and may refer to an orchestration function. The platform function, or orchestration function, may include a middleware application or infrastructure service to compose the MEC system structure. That is, the platform functionality 270 is the arrangement and distribution of each edge server 151 constituting the edge network 150, and the edge application package is injected to the edge server 151 or the edge application server 250 ), and a function of setting information (eg, IP address, FQDN) of the edge application server 250 to the edge server 151, and the like. In addition, the platform functionality 270 provides platform services (eg, network status reporting, traffic route change request of the terminal 120, location information reporting of the terminal 120, etc.) provided by using the 5G system as an edge application server ( 250) can be supported. In addition, the platform functionality 270 may be called a term such as a multi-access edge platform, edge computing infra, and the like, and is not limited to the term, and the edge servers constituting the edge network perform a platform function of a connected system. If it means a function, this can be the case.

3 shows a PDU session establishment operation for establishing a data connection by a terminal accessing a 5G system according to an embodiment of the present invention. Through this procedure, the terminal can receive information on the server to which it should initially access.

According to an embodiment of the present invention, through the procedure of FIG. 3, the terminal 120 obtains DNS server information from the 5G system to find the edge server 151 to which the terminal 120 should access to use the MEC service. Suggest a way to do it. The DNS server 154 may be used to resolve the IP address of the edge server 151 or to resolve the IP address of an application application server running on the edge server. That is, the DNS server 154 may be a network function that knows information about the edge server 151 or information about an application application server running on the edge server. The DNS server 154 may exist for each edge network covering a specific area, or one may exist in the entire MEC system.

In another embodiment, through the procedure of FIG. 3, the terminal 120 is an address to the initial access server 153 through which the terminal 120 can receive configuration information for using the MEC service from the 5G system (for example, , IP address or FQDN). In the present invention, the initial access server 153 means a server that provides configuration information for the terminal 120 to use the MEC service, and is referred to as a MEC configuration server. The MEC configuration server 153 performs a function of transmitting configuration information for using the MEC service to the terminal 120. The configuration server 153 knows the deployment of edge servers 151 for each location. Before using the MEC service, the terminal 120 may access the configuration server 153 to receive configuration information necessary for using the MEC service, for example, information on the edge server 151 to be accessed at a specific location.

The steps of FIG. 3 may be applied to at least one of 1) an embodiment in which the address of the DNS server 154 is set and 2) an embodiment in which the address of the MEC configuration server 153 is set.

In step 310, in order to establish a PDU session, the UE (terminal) 120 may configure a PDU session establishment request, which is an SM NAS message, and transmit it to the AMF 112 (via the base station 111). The terminal 120 may transmit to the AMF 112 including the DNN (data network name) that it intends to use in the PDU session establishment message, and the terminal 120 may set this DNN as a DNN value for MEC. Alternatively, the default DNN that the terminal 120 should use in the 5G system may be a DNN that can use MEC. The DNN information may be used in a later step when the SMF 113 or the PCF 114 determines whether the corresponding DNN is a DNN for MEC permitted to be used by the terminal 120. The DNN value for MEC may be based on a value preset in the terminal 120. Alternatively, the terminal 120 may include an indicator in the PDU session establishment message indicating that the PDU session requested by it is a PDU session to use the MEC service. When a mobile communication service provider uses a DNN as a general DNN, for example, an internet DNN for MEC service, when the terminal 120 requests a PDU session with the internet DNN, it is determined whether the corresponding PDU session is a PDU session to use MEC. Since this is not possible, the terminal 120 may include the indicator as described above in a message and transmit it to the AMF 112. The indicator may include a meaning that it is necessary to apply a session policy for MEC service to the corresponding PDU session. Alternatively, the indicator may indicate the ID of a service provider providing the MEC service, which may be used in the 5G system in the form of an AF service identifier. The AF service identifier may be information pre-configurated in the MEC service support function in the terminal, or information included in configuration information for the MEC service in the terminal. The indicator expressed as described above may be used when determining that the SMF 113 or the PCF 114 can apply the MEC service to the corresponding PDU session in a later step.

In step 315, the AMF 112 may select the SMF 113 based on the DNN value or the location of the terminal 120, and transmit the Nsmf_PDUSession_CreateSMContext request message to the selected SMF 113. The AMF 112 includes a PDU session establishment request message received from the terminal 120 in this message.

In step 320, the SMF 113 sees the PDU session establishment request message received from the terminal 120, and in order to obtain session-related subscription information for the terminal 120, the user 113 serves to the UDM 117. A procedure for registering the SMF and a procedure for obtaining subscription information for session management of the corresponding terminal 120 may be performed.

As an optional operation, the SMF 113 in the step of obtaining the subscription information from the UDM 117, the SMF 113, if the PDU session establishment request message received from the terminal 120 in step 310, the MEC DNN If included, the SMF 113 may include an indicator requesting subscription information for the MEC service in a message sent to the UDM 117 to obtain subscription information for the MEC DNN. Alternatively, if the SMF 113 includes an indicator that the terminal 120 wants to use the MEC service in step 310, the SMF 113 subscribes to the message sent to the UDM 117 based on this indicator for the MEC service. You can include an indicator to request information. The indicator may mean an identifier indicating MEC service data among subscription information. Upon receiving this, the UDM 117 may provide the SMF 113 with subscription information for the MEC service. This subscription information includes authorization information on whether the terminal 120 can use the MEC service, information on an area in which the terminal 120 can use the MEC service, or DNS server information that the terminal 120 should use or the terminal ( 120) MEC configuration server information that should receive configuration information through initial access, or an AF service identifier indicating a MEC service provider ID used by the terminal may be included.

In step 325, the SMF 113 reports the PDU session establishment request message received from the terminal 120, and performs a procedure for establishing an SM policy association with the PCF 114 for the corresponding DNN. At this time, the SMF 113 may transmit the DNN requested by the terminal 120 to the PCF 114. Upon receiving this information, the PCF 114 may determine that the corresponding DNN is a DNN for MEC service, and then configure a session-related policy to be transmitted to the SMF 113 including information that can use the MEC service. Or, if the terminal 120 includes an indicator for using the MEC service in the PDU session establishment request in step 310, the SMF 113 provides an indicator notifying the PCF 114 that the corresponding PDU session is for using the MEC service. In addition, the SM policy association establishment procedure may be performed, and the PCF 114, which has received it, may configure a session-related policy to be transmitted to the SMF 113, including information that can use the MEC service. As another detailed example, the indicator may be in the form of an AF service identifier indicating an ID of an MEC service provider. This may be an indicator received from the terminal or an indicator obtained from subscription information of the terminal. In addition, when performing the SM policy association establishment procedure in the PCF 114, the SMF 113 includes information on the location of the current terminal 120 (eg, cell ID, tracking area, etc.), and the PCF 114 Can tell. When the PCF 114 then transmits MEC-related information to the SMF 113 for the PDU session of the corresponding terminal 120, it may determine which information to inform based on the location information of the terminal 120. .

In addition, according to the optional operation of step 320, the SMF 113 can see the subscriber information of the terminal 120 and check whether the corresponding terminal 120 and the DNN requested by the corresponding terminal 120 are permitted to use the MEC service. have. The SMF 113 indicates that if the terminal 120 is a terminal permitted to use the MEC service, or if the DNN requested by the terminal 120 is a DNN permitted to use the MEC service, an indicator indicating that the use of the MEC service is permitted or the MEC service When making a policy association with the PCF 114, an indicator of a DNN to be used or an AF service identifier indicating an ID of a MEC service provider may be transmitted to the PCF 114. Based on this, the PCF 114 may configure MEC service related information for the corresponding terminal and transmit it to the SMF 113. Alternatively, the PCF may determine that the DNN included in the request is a DNN used for MEC service for the policy association requested from the SMF, and then determine to configure MEC service related information for the corresponding terminal.

The information for the MEC service may be included in the session-related policy information that the PCF 114 should provide to the SMF 113 through the above procedure. The PCF 114 may determine whether to give information for the MEC service based on user information stored in a UDR (unified data repository). At this time, considering which MEC service provider is used, it can be determined whether to give information on the corresponding MEC service. The information for the MEC service may mean a DNS server address to which the terminal 120 should access when using the MEC service through a corresponding PDU session. As another example, the information for the MEC service may mean an initial access server, that is, the address of the MEC configuration server, to which the terminal 120 should access in order to receive related configuration information when using the MEC service through a corresponding PDU session. The address of the DNS server 154 or the address of the MEC configuration server 153 may follow the format of an IP address. Alternatively, the address of the MEC configuration server 153 may follow the FQDN format, and in this case, the terminal 120 may obtain the IP address of the MEC configuration server 153 through a DNS query when receiving this FQDN in a later step. I can. When determining which MEC service information is to be provided for the corresponding PDU session, the PCF 114 considers the location of the terminal 120 received from the SMF 113 and is closest to the current location of the terminal 120. The address of the DNS server 154 or the address of the MEC configuration server 153 may be informed to the SMF 113. As another example, when determining the address of the DNS server 154 or the address of the MEC configuration server 153 that can be accessed and used at the current location of the terminal 120, the PCF 114 considers the load state of the network. SMF 113 by selecting information on the server closest to the current location of the terminal 120 (or the terminal 120 can use at the current location) among the DNS server 154 or the MEC configuration server 153 that is not heavily loaded. ) Can be provided.

According to an embodiment, the PCF 114 updates the address of the DNS server 154 or the address of the MEC configuration server 153 corresponding to the location of the terminal 120 to the SMF 113, the location of the terminal 120 Events for changes can be subscribed to the SMF (113). When the PCF 114 subscribes to the location change event of the terminal 120 to the SMF 113, it may request by setting an area of interest (AoI) (a region in which the mobility of the terminal 120 is to be determined). It can be configured as a tracking area list or a cell list. When determining the area of interest (AoI), the PCF 114 may be determined by considering area information that can be covered by the edge network 150 available in the current area of the terminal 120. For example, the PCF 114 may set the SMF 113 to provide a report on an event when the terminal 120 is out of a specific area corresponding to the AoI, and the PCF 114 transmits the event report to the SMF 113 When received from, the location of the terminal 120 may be determined again at that time, and the address of the DNS server 154 or the address of the MEC configuration server 153 may be updated to the SMF 113.

When the PCF 114 provides the address of the DNS server 154 or the address of the MEC configuration server 153, the PCF 114 may configure a mapping for which server information should be used in which region and transmit it to the SMF 113. . For example, the address of the DNS server 154 to be accessed from Tracking Area 1, Tracking Area 2, Tracking Area 3, and Tracking Area 4 or the address of the MEC configuration server 153, Tracking Area 10, Tracking Area 11, Tracking The address of the DNS server 154 to be accessed in Area 12 or the address of the MEC configuration server 153 may be configured as a list and transmitted to the SMF 113. Upon receiving the information, the SMF 113 determines the mobility of the terminal 120 in the future, and determines the address of the DNS server 154 or the address of the MEC configuration server 153 to be accessed in the region where the terminal 120 is currently located. It can be determined that the update should be made to the terminal 120. According to an embodiment, the SMF 113 receiving the information from the PCF 114 maps the address of the DNS server 154 or the address of the MEC configuration server 153 with location information (eg, tracking area list). It can be determined to be delivered to the terminal 120 by configuring a list.

According to an embodiment, in addition to the above information, the PCF 114 provides authorization information on whether the terminal 120 can use the MEC service, and information on an area in which the terminal 120 can use the MEC service (tracking area list or cell List, etc.), SMF 113, including information on the period in which the terminal 120 can use the MEC service (for example, for the next one month, or from a few months to a few months) Can be delivered to If the SMF 113 receives the area information, it may determine that it cannot provide a PDU session using the MEC service to the terminal 120 when the terminal 120 leaves the corresponding area, and the PCF 114 The current location of the terminal 120 may be notified and a new policy may be requested or the PDU session of the terminal 120 may be released. If the SMF 113 receives the time information, it may determine that it cannot provide the PDU session using the MEC service to the terminal 120 at the time that the corresponding time has elapsed, and request a new policy from the PCF 114 The PDU session of the terminal 120 may be released.

The PCF 114 transmits a policy and charging control (PCC) rule to be applied by the SMF 113 for the PDU session that the terminal 120 intends to use. The information proposed in the above embodiment may be included as part of the PCC rule, or may be separately configured and transmitted as information for MEC service in addition to the PCC rule. When configuring the PCC rule, the PCF 114 can identify the traffic detection rule, the traffic forwarding rule, or the UPF 116 to be allocated to establish the corresponding PDU session in order to provide MEC service in the corresponding PDU session. It may include a list of existing information (eg, data network access identity (DNA)). After receiving this information, the SMF 113 selects the UPF 116 based on this information, and the UPF 116 This can be applied when sending a session establishment request to a user.

In step 330, the SMF 113 performs a UPF selection procedure based on the policy information received from the PCF 114, and performs an N4 session establishment procedure with the selected UPF 116. If the SMF 113 receives the DNAI list from the PCF 114, the SMF 113 selects the UPF 116 corresponding to the DNAI that can be connected based on the current location of the terminal 120. If the information received from the PCF 114 includes area information that can use the DNN for MEC, the SMF 113 provides the UPF 116 that can support the corresponding service area based on the current location of the terminal 120. Choose. When selecting the UPF 116, the SMF 113 determines whether the UPF 116 is a UPF that can be connected to the edge network 150 to which the PDU session requested by the terminal 120 is accessed, and uses the corresponding edge network 150. Select a UPF that can be connected. In addition, the SMF 113 performs an N4 session establishment procedure, including forwarding DNAI, packet forwarding action rules, and packet enforcement rules to the corresponding UPF 116 to enable data transmission and reception through the edge network 150.

In step 335, the SMF 113 may configure a PCO to be provided to the terminal 120 based on the session-related policy information received from the PCF 114. PCO is an abbreviation of protocol configuration options, and is a container that contains additional configuration information necessary to use a corresponding PDU session, and is information exchanged between the terminal 120 and the SMF 113. The SMF 113 may include the address of the DNS server 154 or the MEC configuration server 153 received from the PCF 114 in the PCO. If the SMF 113 is a pair of the address of the DNS server 154 or the MEC configuration server 153 from the PCF 114 and an area in which the address value is available (eg, tracking area list, cell list, etc.) Upon receiving the made list, the SMF 113 may include this list in the PCO and transmit it to the terminal 120. Alternatively, the SMF 113 is a pair of the address of the DNS server 154 or the MEC configuration server 153 from the PCF 114 and an area in which the address value is available (eg, tracking area list, cell list, etc.). Upon receiving the made list, the SMF 113 may configure the address of the DNS server 154 or the MEC configuration server 153 according to the location of the current terminal 120 as a PCO and transmit it to the terminal 120.

Alternatively, the SMF 113 may configure the PCO according to the pre-configuration value in the SMF 113. If the information on the address of the DNS server 154 or the MEC configuration server 153 is not included in the information received by the SMF 113 from the PCF 114, or regardless of the policy procedure with the PCF 114, The SMF 113 may include the DNS server 154 or the address of the MEC configuration server 153 in the PCO providing the terminal 120 according to a preset value. A list consisting of pairs of addresses of the DNS server 154 or MEC configuration server 153 in the information previously set in the SMF 113 and regions where the address values are available (eg, tracking area list, cell list, etc.) If there is, the SMF 113 may include this list in the PCO and transmit it to the terminal 120. Alternatively, a pair of the address of the DNS server 154 or the MEC configuration server 153 and an area in which the address value is available (eg, tracking area list, cell list, etc.) in information preset in the SMF 113 If there is a list, the SMF 113 may configure the address of the DNS server 154 or the MEC configuration server 153 according to the location of the current terminal 120 as a PCO and transmit it to the terminal 120.

The PCO may be included in a session management NAS message called PDU session establishment accept and delivered to the terminal 120 as a NAS message through the AMF 112.

The SMF 113 may include a PDU session establish accept message delivered to the terminal 120 and an N2 message delivered to the base station 111 in the Namf_Communication_N1N2messageTransfer message and send to the AMF 112. The N2 message includes PDU session ID, QoS profile, QoS flow ID, tunnel information of the UPF 116 side for N3 tunnel connection between the UPF 116 and the base station 111, and the like.

The AMF 112 may transmit an ACK for Namf_Communication_N1N2messageTransfer to the SMF 113.

In step 340, the AMF 112 delivers the message received from the SMF 113 to the base station 111. This message includes the N2 SM message received from the SMF 113, and the N1 SM NAS message received from the SMF 113.

In step 345, the base station 111 receives the message of step 340, and performs an RRC signaling procedure for establishing a data radio bearer with the terminal 120 according to QoS information contained in the N2 SM message. Also, the base station 111 delivers the received NAS message to the terminal 120.

Upon receiving the PDU session establishment accept message sent by the SMF 113, the terminal 120 completes the PDU session establishment procedure. The terminal 120 checks the PCO information included in the PDU session establishment accept message, and checks the address of the DNS server 154 or the MEC configuration server 153 included in the PCO. Through this information, the terminal 120 can know which DNS server 154 to access for the corresponding PDU session. Alternatively, when the terminal 120 checks the address of the MEC configuration server 153, for the corresponding PDU session, the terminal 120 may know the address of the server to which the initial connection is to be made. After the NAS layer of the terminal 120 checks this information, it transmits it to the upper layer (ie, enabling layer) 220 through an AT command. AT command is a command transmission method between the 3GPP communication layer 230 and an upper layer (eg, the application layer 210, including the enabling layer 220 according to the structure of the present invention), and provides necessary information when using a network. It refers to the action notified to the upper layer. The enabling layer 220 of the terminal 120 can register an AT command connection with the NAS layer of the 3GPP communication layer 230, through which a command to inform the address of the DNS server 154 is registered, or A command to inform the address of the configuration server 153 can be registered. The NAS layer 230 of the terminal 120, which has confirmed the PCO of the SM NAS message through step 345, sends the DNS server address or the MEC configuration server address that it received as the PCO to the enabling layer 220 according to the registered AT command. Deliver. The enabling layer 220 stores this information. When the DNS server address is received by the AT command, the enabling layer 220 stores the DNS server address, and then checks the stored DNS server address when a DNS query occurs from the App using the corresponding DNN (i.e., DNN for MEC). Send a DNS query to (154). When the enabling layer 220 receives the MEC configuration server address as an AT command, the enabling layer 220 stores it and then registers it in the MEC service or uses it to access the MEC configuration server 154 to receive necessary configuration information. do. The NAS layer 230 of the terminal 120 is a PCO for the address of the DNS server 153 or the MEC configuration server 153 and the area in which the address value is available (eg, tracking area list, cell list, etc.). If a paired list is received, it can be transmitted to the enabling layer 220 as an AT command. The enabling layer 220 stores this information. In this case, the enabling layer transmits a DNS query to the server 154 by checking the stored location information and the corresponding DNS server address when a DNS query occurs from the App using the corresponding DNN (i.e., DNN for MEC). If the enabling layer 220 receives the MEC configuration server address and its location information by AT command, the enabling layer stores it and then registers it with the MEC service or sends the MEC configuration server 153 to receive necessary configuration information. In order to access, based on the location of the current terminal 120, the corresponding MEC configuration server 153 is checked, and the server is accessed.

In step 350, the base station 111 sends a response to step 340 to the AMF 112. This message includes an N2 SM message, which includes the PDU session ID and tunnel information of the base station for N3 tunnel connection with the UPF. In addition, the message may include information such as established QoS Flow.

The AMF 112 receiving the message in step 350 may deliver the N2 SM message contained in the message in step 350 to the SMF 113 in step 355.

In step 360, the SMF 113 reports the N2 SM message received in step 355, and performs an N4 session modification procedure with the UPF 116. In this case, the SMF 113 may transmit the N3 tunnel information received from the base station 111 to the UPF 116 and may also transmit a packet forwarding rule for this. Through this step, it can be seen that the UPF 116 and the base station 111 have established a tunnel connection for data transmission/reception.

In step 365, the SMF 113 may send a response to step 355 to the AMF 112.

Now, the terminal 120 can transmit and receive data through the established PDU session.

4 illustrates a procedure for receiving policy information from a 5G system after a terminal accesses a 5G system and performs a registration procedure according to an embodiment of the present invention. Through this procedure, the terminal can receive the policy including the information of the server to be initially accessed.

According to an embodiment of the present invention, through the procedure of FIG. 4, the terminal 120 is a DNS server 154 through which the terminal 120 can find the edge server 151 to which the terminal 120 should access in order to use the MEC service from the 5G system. We propose a method of obtaining information as part of policy information. The DNS server 154 may be used to resolve the IP address of the edge server 151 or to resolve the IP address of an application application server running on the edge server 151. That is, the DNS server 154 may be a network function that knows information about the edge server 151 or information about an application application server running on the edge server 151. The DNS server 154 may exist for each edge network covering a specific area, or one may exist in the entire MEC system.

In step 410, the terminal 120 may perform a registration procedure to register with the 5G system. The terminal 120 accesses the 5G system for the first time, or periodically informs the 5G system of its reachability, or the terminal 120 is located in a different area due to mobility, so that it is out of the registration area allocated from the 5G system. , Or when you want to change the service you want to use (eg, change a network slice, etc.), or you can perform a registration procedure to request policy information. After establishing the RRC connection with the base station 111, the terminal 120 may include a registration request message, which is a NAS message sent to the AMF 112, in the RRC message. According to a detailed embodiment of the present invention, the terminal 120 may send a registration request message including an identifier (NSSAI) indicating a network slice for MEC. Alternatively, according to a detailed embodiment of the present invention, the terminal 120 may send a registration request message including a NAS message requesting a policy from the PCF 114 (ie, a UE STATE INDICATION message). After determining that the MEC service will be used, the UE 120 may include an identifier for requesting a policy for the MEC service in the UE STATE INDICATION message (ie, UE policy section identifier, for short UPSI). Depending on the embodiment, the enabling layer 220 for the MEC service in the terminal 120 may request the NAS layer of the 3GPP layer 230 that the MEC policy information is required, and based on this, the NAS layer The UPSI can be determined by deciding that the policy should be requested. The UPSI information may be used to determine that the PCF 114 should provide a policy for the MEC service to the terminal 120 in a later step. In addition, the terminal 120 may include an identifier (eg, Android, IOS, etc.) of an operating system driven by the terminal 120 in the UE STATE INDICATION message. Additionally, the terminal 120 may include information capable of identifying up to the version of the operating system (eg, Android 9.0, IOS 12.1, etc.).

In step 420, the AMF 112 may see the ID of the terminal 120 contained in the registration request message sent from the terminal 120, and infer the AMF that previously served the terminal 120. The AMF 112, which determines that there is an AMF that previously served the terminal 120, may request the context of the terminal 120 from the corresponding AMF. After the AMF 112 receives the context of the terminal 120, it is stored and used to manage the terminal 120. According to an embodiment, the AMF 112 that determines that the terminal 120 accesses the 5G system for the first time may create a context for managing the terminal 120. The AMF 112 performs a registration procedure with the UDM 117 to inform the UDM 117 that it has served the terminal 120, and also performs a procedure of acquiring the subscription information of the terminal 120. I can.

In step 430, when the terminal 120 performs an initial registration procedure, the AMF 112 may perform an AM policy association establishment procedure to obtain policy information necessary for managing the terminal 120. Alternatively, if the terminal 120 that sent the registration request is not the terminal that it was serving, the AMF 112 does not have previously stored policy information necessary to manage the terminal 120, so that the PCF 114 ) And AM policy association update procedure. Through this procedure, the AMF 112 can manage the terminal 120 by acquiring policy information for managing access or mobility of the terminal 120 and storing it in the context of the terminal 120.

In step 435, the AMF 112 sends the registration request message including a NAS message requesting a policy from the PCF 114 (ie, a UE STATE INDICATION message), and the terminal 120 If the serving AMF is changed due to the initial registration procedure or the mobility of the terminal 120, the AMF 112 performs a procedure for establishing a UE policy association with the PCF 114 in order to receive policy information for the terminal 120. can do. According to an embodiment, if there is a PCF 114 in which the AMF 112 has previously established a UE policy association, and the terminal 120 sends a NAS message requesting a policy (ie, a UE STATE INDICATION message), the AMF 112 ) May send a UE policy update request to the PCF 114. The AMF 112 may inform the PCF 114 of the current location of the terminal 120 through this procedure.

The AMF 112 delivers the UE STATE INDICATION message, which is a policy NAS message received from the terminal 120, to the PCF 114 through a registration procedure. Upon receiving the UE STATE INDICATION message, the PCF 114 checks the UPSI in the UE STATE INDICATION message. If the terminal 120 includes an identifier for requesting policy information for MEC as the UPSI value of the UE STATE INDICATION message in step 410, the PCF 114 determines that the terminal 120 requests policy information for using the MEC service. can do. The PCF 114 may check whether the terminal 120 is a terminal capable of using the MEC service based on subscription information. When the operating system ID that is driven by the terminal 120 is included in the UE STATE INDICATION message sent from the terminal 120, the PCF 114 identifies the operating system used by the terminal 120 based on this information, and You can configure policy information applicable to the operating system. For example, the PCF 114 may determine whether the MEC can be used for a specific application in the Android OS or whether the MEC DNN can be used, and then apply it when configuring policy information. In addition, if the PCF 114 receives the current location of the terminal 120 from the AMF 112, it may determine policy information necessary for the MEC service according to the current location of the terminal 120. Since the main purpose of the MEC service is to use a network close to a specific area, it is not necessary to provide information for the MEC service that is remote from the current location of the terminal 120, so the PCF 114 Policy information required for MEC service can be determined based on the location. Alternatively, the PCF 114 may determine to provide information for all MEC services that the terminal 120 can use in the corresponding PLMN, regardless of the current location of the terminal 120.

According to an embodiment of the present invention, the PCF 114 configures policy information for providing policy information for MEC service to the terminal 120 requesting 1) UE route selection policy (URSP) or 2) MEC policy type. I can.

1) URSP is an abbreviation of UE route selection policy. What is the SSC mode that the terminal 120 should use when transmitting and receiving data, what network slice should be used, what DNN should be used, what PDU session type ( For example, whether it is IPv4 or IPv6), which access type (eg, RAN or WiFi, etc.) should be used, and which IP address should be used. URSP consists of a traffic descriptor and a route selection descriptor. The traffic descriptor may include App ID, destination IP 3 tuple (address, protocol ID, port number), destination FQDN, DNN, connection capability (IMS, MMS, Internet, etc.). After determining whether the traffic transmitted from the application layer 210 of the terminal 120 is matched according to this traffic descriptor, SSC mode, network slice information, DNN, PDU session type (IPv4, IPv6, etc.) included in the route selection descriptor, It is possible to connect to a PDU session by applying an access type (3GPP or Non3GPP). For example, when the application A of the terminal 120 requests traffic to which FQDN, find the traffic descriptor for the corresponding app ID and destination FQDN, see the route selection descriptor for the traffic descriptor, and which DNN to use. I can judge. According to an embodiment of the present invention, the PCF 114 may additionally configure and apply information necessary for the MEC service to the URSP to the terminal 120 using the MEC service. In a method according to an embodiment of the present invention, information necessary for the MEC service added to the URSP may consist of at least one of the following.

Information added to [traffic descriptor]

-Connection capability to use MEC service

-Application (OS ID + OS application ID) identifier for which MEC is supported

-FQDN to access to use MEC service

-Location information list for which the traffic descriptor is valid (for example, tracking area list, cell list, PLMN list, GPS information, etc.)

-Time information for which the traffic descriptor is valid (e.g., January 2, 2019 to February 2, 2019, March 4, 2019 to March 4, 2020, the time zone to which the current terminal belongs or the UTC standard time Information, etc.)

Information added to [route selection descriptor]

-DNS server address or FQDN to which the terminal 120 should access

-The DNS server address or FQDN is a valid location information list (for example, tracking area list, cell list, PLMN list, GPS information, etc.) or valid time

-MEC configuration server address or FQDN to which the terminal 120 should access

-The MEC configuration server address or FQDN is a valid location information list (for example, tracking area list, cell list, PLMN list, or GPS information) or valid time

When it is determined that the MEC service is used by the traffic descriptor based on the added information as described above, the route selection descriptor is applied. Determining that the MEC service is used by the traffic descriptor means that the traffic requested by the application of the terminal 120 is traffic using the DNN for MEC, or that the traffic requested by the application of the terminal 120 is a connection using the MEC service connection capability. It may mean that the application indicated in or requesting traffic is an application for using MEC service.

Depending on the embodiment, when determining the DNS server 154 or the MEC configuration server 153 information, the PCF 114 has the least load in consideration of the load situation of the server, or the current location of the terminal 120 It is possible to select a server for the MEC service that supports the nearest or the service area including the current location of the terminal 120.

2) In a method according to an embodiment of the present invention, the PCF 114 may configure policy information for MEC service in an independent policy format such as ANDSF and URSP. In the present invention, this will be called MEC policy for convenience. The PCF 114 may configure information that the terminal 120 should use for the MEC service in the MEC policy and transmit it to the terminal 120. Information entering the MEC policy may consist of at least one or more of the following.

-Application (OS ID + OS application ID) identifier for which MEC is supported

-FQDN to access to use MEC service

-Location information list for which MEC policy is valid (eg, tracking area list, cell list, PLMN list, or GPS information)

-Time information for which the MEC policy is valid (e.g., January 2, 2019 to February 2, 2019, March 4, 2019 to March 4, 2020, the time zone to which the current terminal belongs or the UTC time Information, etc.)

-DNS server address or FQDN to which the terminal 120 should access

-The DNS server address or FQDN is a valid location information list (for example, tracking area list, cell list, PLMN list, GPS information, etc.) or valid time

-MEC configuration server address or FQDN to which the terminal 120 should access, or the address or FQDN of the server to which the terminal 120 using the MEC service should perform initial access

-The MEC configuration server or the server address or FQDN to perform initial access is a valid location information list (e.g., tracking area list, cell list, PLMN list, or GPS information) or valid time

Depending on the embodiment, when determining the DNS server 154 or the MEC configuration server 153 information, the PCF 114 has the least load in consideration of the load situation of the server, or the current location of the terminal 120 It is possible to select a server for the MEC service that supports the nearest or the service area including the current location of the terminal 120.

This information is transmitted to the terminal 120 and the operation will be described in detail later. After configuring the policy information as described above, the PCF 114 may include it in the NAS message of MANAGE UE POLICY COMMAND and transmit it to the AMF 112. The AMF 112 does not interpret this message and can recognize it as a container containing policy information. The AMF 112 may deliver a NAS message (ie, a policy container) containing the policy information received from the PCF 114 to the terminal 120 through step 440.

In step 440, the AMF 112 may transmit a registration accept message to the terminal 120 to accept the registration procedure of the terminal 120. If the AMF 112 performs step 435 and receives the policy container to be delivered to the terminal 120 through step 435 from the PCF 114, the AMF 112 includes this policy container in the registration accept message to the terminal 120. I can deliver.

The terminal 120 may receive a registration accept message. If the registration accept message includes a policy container, for example, a MANAGE UE POLICY COMMAND message sent by the PCF 114 through the AMF 112, the terminal 120 checks and applies it to the terminal operation. A procedure for applying the policy information received by the terminal 120 will be described later.

In step 450, if the terminal 120 is newly assigned a globally unique temporary identifier (GUTI) through the registration accept message in step 440, it may send a registration complete message to the AMF 112 to complete the registration procedure. According to an embodiment, if the terminal 120 receives the MANAGE UE POLICY COMMAND message through the registration accept message in step 440, the MANAGE UE POLICY COMPLETE message indicating that it has been properly applied may be stored in the policy container and delivered to the AMF 112. . The AMF 112 may transmit this to the PC 114 F.

When the PCF 114 does not provide policy information for using the MEC service to the terminal 120 through steps 410 to 450, that is, the terminal 120 requests the policy information in the registration request message, the UE STATE If the INDICATION message is not included, the PCF 114 can know which terminal 120 is connected to the network according to the AM policy establishment procedure in step 430. Accordingly, the PCF 114 can determine that the corresponding terminal 120 is a terminal using the MEC service by checking subscription information or user information, and determines that the terminal 120 needs to provide policy information necessary for the MEC service. I can. Accordingly, the PCF 114 may perform the operation of step 460 to provide policy information for the MEC service to the terminal 120. According to an embodiment, the PCF 114 performs the operation of step 460 to update the new policy information to the terminal 120 even if policy information for using the MEC service is provided to the terminal 120 through steps 410 to 450. Can be done.

In step 460, the PCF 114 may perform a UE policy update procedure with the AMF 112 to provide policy information to the terminal 120. This operation is a procedure in which the PCF 114 configures the policy information to be delivered to the terminal 120 as a NAS message and delivers it to the AMF 112 in the form of a policy container, and the AMF 112 receives through this procedure. Policy information may be delivered to the terminal 120 in a later step.

The PCF 114 determines that the terminal 120 is a terminal using the MEC service based on subscription information or user information stored in the PCF 114 or obtained from the UDR, and then for the terminal 120 in step 435 Policy information for the MEC service according to the described embodiment of the present invention can be configured.

According to an embodiment of the present invention, the PCF 114 may configure policy information for providing policy information for MEC service to the terminal 120 requesting 1) URSP or 2) MEC policy type.

1) URSP is an abbreviation of UE route selection policy. What is the SSC mode that the terminal 120 should use when transmitting and receiving data, what network slice should be used, what DNN should be used, what PDU session type ( For example, whether it is IPv4 or IPv6), which access type (eg, RAN or WiFi, etc.) should be used, and which IP address should be used. URSP consists of a traffic descriptor and a route selection descriptor. The traffic descriptor may include App ID, destination IP 3 tuple (address, protocol ID, port number), destination FQDN, DNN, connection capability (IMS, MMS, Internet, etc.). After determining whether the traffic transmitted from the application layer 210 of the terminal 120 is matched according to this traffic descriptor, SSC mode, network slice information, DNN, PDU session type (IPv4, IPv6, etc.) included in the route selection descriptor, It is possible to connect to a PDU session by applying an access type (3GPP or Non3GPP). For example, when the application A of the terminal 120 requests traffic to which FQDN, find the traffic descriptor for the corresponding app ID and destination FQDN, see the route selection descriptor for the traffic descriptor, and which DNN to use. I can judge. According to an embodiment of the present invention, the PCF 114 may additionally configure and apply information necessary for the MEC service to the URSP to the terminal 120 using the MEC service. In a method according to an embodiment of the present invention, information necessary for the MEC service added to the URSP may include at least one of the following.

Information added to [traffic descriptor]

-Connection capability to use MEC service

-Application (OS ID + OS application ID) identifier for which MEC is supported

-FQDN to access to use MEC service

-Location information list for which the traffic descriptor is valid (for example, tracking area list, cell list, PLMN list, GPS information, etc.)

-Time information for which the traffic descriptor is valid (e.g., January 2, 2019 to February 2, 2019, March 4, 2019 to March 4, 2020, the time zone to which the current terminal belongs or the UTC standard time Information, etc.)

Information added to [route selection descriptor]

-DNS server address or FQDN to which the terminal 120 should access

-The DNS server address or FQDN is a valid location information list (for example, tracking area list, cell list, PLMN list, GPS information, etc.) or valid time

-MEC configuration server address or FQDN to which the terminal 120 should access

-The MEC configuration server address or FQDN is a valid location information list (for example, tracking area list, cell list, PLMN list, or GPS information) or valid time

When it is determined that the MEC service is used by the traffic descriptor based on the added information as described above, the route selection descriptor is applied. Determining that the MEC service is used by the traffic descriptor means that the traffic requested by the application of the terminal 120 is traffic using the DNN for MEC, or that the traffic requested by the application of the terminal 120 is a connection using the MEC service connection capability. It may mean that the application indicated in or requesting traffic is an application for using MEC service.

Depending on the embodiment, when determining the DNS server 154 or the MEC configuration server 153 information, the PCF 114 has the least load in consideration of the load situation of the server, or the current location of the terminal 120 It is possible to select a server for the MEC service that supports the nearest or the service area including the current location of the terminal 120.

2) In a method according to an embodiment of the present invention, the PCF 114 may configure policy information for MEC service in an independent policy format such as ANDSF and URSP. In the present invention, this will be called MEC policy for convenience. The PCF 114 may configure information that the terminal 120 should use for the MEC service in the MEC policy and transmit it to the terminal 120. Information entering the MEC policy may consist of at least one or more of the following.

-Application (OS ID + OS application ID) identifier for which MEC is supported

-FQDN to access to use MEC service

-Location information list for which MEC policy is valid (eg, tracking area list, cell list, PLMN list, or GPS information)

-Time information for which the MEC policy is valid (e.g., January 2, 2019 to February 2, 2019, March 4, 2019 to March 4, 2020, the time zone to which the current terminal belongs or the UTC time Information, etc.)

-DNS server address or FQDN to which the terminal 120 should access

-The DNS server address or FQDN is a valid location information list (for example, tracking area list, cell list, PLMN list, GPS information, etc.) or valid time

-MEC configuration server address or FQDN to which the terminal 120 should access, or the address or FQDN of the server to which the terminal 120 using the MEC service should perform initial access

-The MEC configuration server or the server address or FQDN to perform initial access is a valid location information list (e.g., tracking area list, cell list, PLMN list, or GPS information) or valid time

Depending on the embodiment, when determining the DNS server 154 or the MEC configuration server 153 information, the PCF 114 has the least load in consideration of the load situation of the server, or the current location of the terminal 120 It is possible to select a server for the MEC service that supports the nearest or the service area including the current location of the terminal 120.

This information is transmitted to the terminal 120 and the operation will be described in detail later. After configuring the policy information as described above, the PCF 114 may include it in the NAS message of MANAGE UE POLICY COMMAND and transmit it to the AMF 112. The AMF 112 does not interpret this message and can recognize it as a container containing policy information. The AMF 112 may deliver a NAS message (ie, a policy container) containing policy information received from the PCF 114 to the terminal 120 through step 470.

The PCF 114 may not transmit to the terminal 120 by configuring the address of the DNS server 154 or the address of the MEC configuration server 153 that can access each location in a list. In this case, the PCF 114 needs to provide the address of the DNS server 154 or the address of the MEC configuration server 153 suitable for the corresponding location based on the current location of the terminal 120. Accordingly, the PCF 114 may set a location monitoring event to the AMF 112 in order to determine a change in the location of the terminal 120. The PCF 114 may subscribe to a monitoring event to the AMF 112 by setting area of interest (ie, a region of interest) information in order to check the mobility of the terminal 120 in a specific area unit. In this case, the AMF 112 informs the PCF 114 along with the location of the terminal 120 when the terminal 120 leaves or enters the area of interest, and the PCF 114 receives the terminal 120 Based on the location of, it may be determined whether the terminal 120 should update the policy for the MEC service.

In step 470, since the AMF 112 is still in a connected state after the terminal 120 has completed registration, the policy information received from the PCF 114 through the step 460 may be transmitted to the terminal 120 as a NAS message. . This NAS message may include a MANAGE UE POLICY COMMAND message sent from the PCF 114 to the terminal 120.

In step 480, the terminal 120 checks the NAS message of step 470 received from the AMF 112, and if the MANAGE UE POLICY COMMAND message is included, it can be checked and applied to the terminal operation. The terminal 120 may put a MANAGE UE POLICY COMPLETE message indicating that it has been applied well in a policy container and deliver it to the AMF 112 in step 480. The AMF 112 may deliver this to the PCF 114 according to step 490. A procedure for applying the policy information received by the terminal 120 will be described below.

If the terminal 120 receives a policy for using the MEC service from the PCF 114 according to the above embodiment, the terminal 120 may apply this to the terminal operation. If the PCF 114 transmits the policy for using the MEC service to the terminal 120 by extension of the URSP, the terminal 120 can operate as follows. If the NAS layer 230 of the terminal 120 receives the URSP from the PCF 114, the URSP information may be transmitted to the layer responsible for the URSP processing of the terminal 120. According to an embodiment, the NAS layer 230 of the terminal 120 may transmit this information to a layer processing URSP through an AT command. AT command is a command transmission method between the 3GPP communication layer 230 and an upper layer (for example, the application layer 210, including the enabling layer 220 or the URSP processing layer according to the structure of the present invention), using a network It means an operation that informs the upper layer of necessary information. The URSP processing layer or enabling layer 220 of the terminal 120 may register an AT command connection with the NAS layer of the 3GPP communication layer 230, and through this, a command to notify URSP information may be registered. The layer responsible for the URSP processing of the terminal 120 may apply the URSP information received from the NAS layer 230. The layer in charge of URSP processing of the terminal 120 may determine whether a connection capability indicating that the MEC service can be used is included in a request from the enabling layer 220 or the application layer 210.

Through the URSP information, the terminal 120 knows which DNS server 154 to access in order to use the MEC service. For example, when the application layer 210 or the enabling layer 220 of the terminal 120 requests DNS resolution to a certain FQDN, it searches for a traffic descriptor that matches the app ID and the destination FQDN, and the traffic descriptor It is possible to determine which DNS server 154 to access and send a query by looking at the route selection descriptor for. In addition, when determining the matching traffic descriptor, the terminal 120 may determine whether it belongs to a valid location information list displayed in the traffic descriptor by considering the current location of the terminal 120. Alternatively, the terminal 120 may determine the address of the DNS server 154 corresponding to the route selection descriptor in consideration of the current location of the terminal 120. Alternatively, the terminal 120 may compare the valid time information displayed in the traffic descriptor with the requested time for DNS resolution, and determine to perform an operation according to the route selection descriptor if the valid time corresponds. Alternatively, the terminal 120 may determine the address of the DNS server 154 for which the current time is determined to be valid, as indicated in the route selection descriptor in consideration of the current time.

Or, if the terminal 120 checks the address of the MEC configuration server 153 (or the address of the server to which the initial connection is to be made) through the URSP, the terminal 120 knows which server to access to use the MEC service. do. For example, in order for the enabling layer 220 of the terminal 120 to initially access the MEC service, it may check information on the server in the URSP and transmit a message to the corresponding server address. In addition, the terminal 120 may determine whether it belongs to a valid location information list displayed in the traffic descriptor in consideration of the current location of the terminal 120. Alternatively, the terminal 120 may determine the address of the MEC configuration server 153 corresponding to the route selection descriptor in consideration of the current location of the terminal 120. Alternatively, the terminal 120 may determine valid time information displayed in the traffic descriptor, and if the valid time corresponds to the valid time, it may determine to initially access the address of the MEC configuration server 153 set according to the route selection descriptor. Alternatively, the terminal 120 may determine the address of the MEC configuration server 153 for which the current time is determined to be valid, as indicated in the route selection descriptor in consideration of the current time.

If the PCF 114 delivers the policy for using the MEC service to the terminal 120 in the form of a MEC policy, the terminal 120 may operate as follows. When the NAS layer 230 of the terminal 120 receives the MEC policy from the PCF 114, it transmits the received MEC policy to the layer 220 in charge of enabling the MEC service of the terminal 120. That is, according to the present invention, the NAS layer 230 of the terminal 120 may transmit the information of the MEC policy to the enabling layer 220. The NAS layer 230 of the terminal 120 may transmit this information to a layer processing MEC policy through an AT command. The AT command is a command transmission method between the 3GPP communication layer 230 and an upper layer (eg, including the application layer 210 and the enabling layer 220 according to the structure of the present invention), and provides necessary information in using the network. It means an action notified to the upper layer. The enabling layer 220 of the terminal 120 may register an AT command connection with the NAS layer of the 3GPP communication layer 230, and through this, a command to inform MEC policy information may be registered. The enabling layer 220 of the terminal 120 applies the MEC policy information received from the NAS layer 230. The enabling layer 220 of the terminal 120 may know which application can use the MEC service, and accordingly, may determine whether to apply the MEC policy.

Through the MEC policy information, the terminal 120 knows which DNS server 154 to access in order to use the MEC service. For example, when the application layer 210 or the enabling layer 220 of the terminal 120 requests DNS resolution with a certain FQDN, the terminal 120 sees the corresponding app ID and destination FQDN, and the DNS server 154 You can determine if you need to connect to and send a query. In addition, the terminal 120 may determine whether the current location of the terminal 120 belongs to a valid location information list displayed in the MEC policy information in consideration of the current location of the terminal 120. Alternatively, the terminal 120 may determine the address of the DNS server 154 corresponding thereto in consideration of the current location of the terminal 120. Alternatively, the terminal 120 may compare valid time information in the MEC policy information with a time when DNS resolution is requested, and determine to perform a DNS query to the corresponding DNS server 154 when a valid time is reached. Alternatively, the terminal 120 may determine the address of the DNS server 154 for which the current time is determined to be valid among the information in the MEC policy information in consideration of the current time, and may perform a DNS query.

Alternatively, when the terminal 120 checks the address of the MEC configuration server 153 (or the address of the server to which the initial connection is to be made) through the MEC policy information, the terminal 120 must access a certain server in order to use the MEC service. You know what to do. For example, in order for the enabling layer 220 of the terminal 120 to initially access the MEC service, it may check the server information in the MEC policy information and transmit a message to the corresponding server address. In addition, the terminal 120 may determine the address of the MEC configuration server 153 corresponding thereto in consideration of the current location of the terminal 120. Alternatively, the terminal 120 may determine whether the time required for initial access corresponds to the valid time information in the MEC policy, and if the time corresponds to the valid time, it may determine to make an initial connection to the address of the set MEC configuration server 153 .

FIG. 5 is a diagram showing a terminal through a PDU session modification procedure according to an embodiment of the present invention,'DNS server information for finding an edge server to which the terminal should access in order to use the MEC service' or'The terminal uses the MEC service. This is a diagram showing a method of updating'MEC configuration server information to be initially accessed for this purpose'.

Through the procedure of FIG. 5, the SMF 113 delivers the updated PCO information to the terminal 120. PCO information for the MEC service may follow the embodiment proposed in FIG. 3 of the present invention.

The PDU session modification procedure can be performed under the following conditions.

-Change of the location of the terminal 120: The SMF 113, which determines that the location of the terminal 120 has changed, allocates a new UPF 116 that is suitable for the current location of the terminal 120, or to the current location of the terminal 120. PDU session modification procedures can be triggered to deliver valid MEC service related information. That is, the SMF 113 provides the address of the DNS server 154 that the terminal 120 can use for MEC service at the current location, or the address of the MEC configuration server 153 to the terminal 120 through PCO. To do this, you can trigger a PDU session modification procedure. Alternatively, the PCF 114, which has determined that the location of the terminal 120 has changed, updates the SM policy association to deliver the MEC service-related information that is valid for the current location of the terminal 120 to the terminal 120, and sends it to the SMF 113. MEC service-related information may be provided, and this information may be transmitted to the terminal 120 through a PDU session modification procedure. That is, after determining the current location of the terminal 120, the PCF 114 determines the DNS server 154 address or the MEC configuration server 153 address that the terminal 120 can use for MEC service at the current location. ) Is transmitted through the SM policy update procedure, and the SMF 113 may perform a PDU session modification procedure to provide this information to the terminal 120 through PCO.

-Change the subscription information of the terminal 120: If the terminal 120 is not using the MEC service and subscribes to additional services of the mobile communication service provider to use the MEC service, the mobile communication service provider sends the MEC to the terminal 120 It can be determined that necessary information must be provided to use the service. Accordingly, the UDM 117 performs a subscription information update procedure with the SMF 113, so that the SMF 113 provides information related to the MEC service to the terminal 120 through the PDU session modification procedure, that is, the terminal 120 uses the MEC service. DNS server 154 or MEC configuration server 153 to be accessed in order to be accessed may be provided. Alternatively, the PCF 114 determines that the value for using the MEC service should be transmitted to the terminal 120 based on the changed subscription information of the terminal 120, and the MEC to the SMF 113 using the SM policy association update procedure. Service-related information can be provided. SMF 113 receiving this is a PDU session so that the terminal 120 can provide the DNS server 154 or MEC configuration server 153 information to be accessed to use the MEC service to the terminal 120 through PCO. Modification procedures can be performed. Conversely, if the terminal 120 is using the MEC service and then cancels the additional service of the mobile communication service provider so that the MEC service is no longer used, the mobile communication service provider makes the terminal 120 no longer use the MEC service. For this purpose, it may be determined to update the PCC rule to the SMF 113 or to provide an updated PCO for invalidating MEC service information that the terminal 120 should use. For example, it may be determined to change the DNS server 154 address for using the MEC service to the DNS server address for the general Internet service. Accordingly, the SMF 113 may provide updated PCO information through a PDU session modification procedure.

- 3 ^rd party requests from: a operator to drive the application on the application providers or service providing MEC MEC service may request a set asking MEC provide services for a particular terminal or DNN. 5G system. This can be provided through a service level agreement or through an OAM system. The mobile communication service provider receiving this may determine to provide necessary information to use the MEC service to a terminal using a corresponding DNN or a specific terminal through a 5G system. Accordingly, the UDM 117 or the PCF 114 may update information on the terminal 120 to information that can use the MEC service, and inform the SMF 113 of this. That is, the UDM 117 may deliver the address of the DNS server 154 or the address of the MEC configuration server 153 that the terminal 120 can use for the MEC service to the SMF 113. Or, the PCF 114 tells the SMF 113 the address of the DNS server 154 that the terminal 120 can use for the MEC service or the address of the MEC configuration server 153 in the PDU session used by the terminal 120. It can be provided as information about SM policy. Alternatively, the OAM system may inform the SMF 113 of the DNS server 154 address or the MEC configuration server 153 address required to provide MEC services in a specific DNN. UDM (117) or PCF (114), or SMF (113) receiving the information from the OAM system, information necessary to use the MEC service, that is, the DNS server 154 address or the address of the MEC configuration server 153 to the terminal ( 120) may perform a PDU session modification procedure. Alternatively, the DNS server 154 address or the MEC configuration server 153 address to be used for MEC can be delivered to the PCO while performing the PDU session modification procedure in order to change the connection of the PDU session used by the terminal 120 to the edge network. have.

-Request from the terminal 120: In order to use the MEC service, the terminal 120 may send a PDU session modification request to the SMF 113 in order to receive information necessary for the MEC service to the PCO. Conversely, in order not to use the MEC service any more, the terminal 120 may notify the SMF 113 that the MEC service is no longer used through the PDU session through a PDU session modification request. Receiving this, the SMF 113 may provide or release information for the MEC service and provide it to the terminal 120 as a PCO. The release method may be a method of omitting a corresponding value from the PCO or including another value (eg, a DNS server for Internet service) in the PCO.

In step 510, in order to change the PDU session, the UE (terminal) 120 may construct a PDU session modification request, which is an SM NAS message, and transmit it to the AMF 112. The terminal 120 includes a data network name (DNN) that it intends to use in the PDU session modification message, which may mean a DNN for MEC. In addition, the terminal 120 may include PCO information in the PDU session modification message, and may include an indicator that requests information from the DNS server 154 or MEC configuration server 153 for the MEC service to the PCO. This can be used later when the SMF 113 sets the corresponding value to the PCO.

In step 515, the AMF 112 may select the SMF 113 and transmit the Nsmf_PDUSession_CreateSMContext request message to the selected SMF 113. The AMF 112 may transmit this message to the SMF 113 including the PDU session modification request message received from the terminal 120. If steps 510 and 515 are performed, the SMF 113 may see the PDU session modification request message received from the terminal 120 and perform a procedure for changing the SM policy association with the PCF 114 for the corresponding DNN. In addition, step 520 may be performed even when steps 510 and 515 are not performed. Step 520 is an operation performed by the PCF 114 to inform the SMF 113 of the updated policy information. This may operate in the case of the request in the case of the above listed conditions, the subscription information is changed, or a 3 ^rd party. The SMF 113, which determines that information for the MEC service has been updated due to this procedure, may update the PCO value and transmit it to the terminal 120, and at this time, an SM NAS message called a PDU session modification command may be used. This message is transmitted to the AMF 112 through step 530, and the AMF 112 may deliver it to the terminal 120 through the base station 111 through steps 535 and 540.

Step 525 is an operation performed by the UDM 117 to inform the SMF 113 of the updated subscription information. Step 525 may occur regardless of step 520. In addition, step 525 may occur regardless of steps 510 and 515. The SMF 113, which determines that it is possible to provide the MEC service to the corresponding terminal 120 due to this procedure, determines the value required for the MEC service (DNS server 154 information or MEC configuration server 153 information, etc.) It can be updated to and delivered to the terminal 120, and at this time, an SM NAS message called PDU session modification command can be used. This message is transmitted to the AMF 112 through step 530, and the AMF 112 may deliver it to the terminal 120 through steps 535 and 540.

In step 530, the SMF 113 may configure an N2 SM message to be transmitted to the base station 111 based on the session-related policy information received from the PCF 114. In addition, the SMF 113 may include the PCO value determined through the above procedure in a message (PDU session modification command) requesting the terminal 120 to change a PDU session. The SMF 113 may send a Namf_Communication_N1N2messageTransfer message to the AMF 112 including the above message. The AMF 112 may transmit an ACK for Namf_Communication_N1N2messageTransfer to the SMF 113.

In step 535, the AMF 112 may deliver the message received from the SMF 113 to the base station 111. This message includes the N2 SM message received from the SMF 113, and the N1 SM NAS message received from the SMF 113.

In step 540, the base station 111 receives the message of step 535 from the AMF 112, and may perform an RRC signaling procedure for establishing a data radio bearer with the terminal 120 according to QoS information contained in the N2 SM message. have. In addition, the base station 111 may deliver the received NAS message to the terminal 120. The terminal 120 checks the N1 SM NAS message received from the SMF 113 and checks the PCO included in the message. The terminal 120 can use the DNS server 154 address or MEC configuration server 153 information included in the PCO for MEC service according to the embodiment illustrated in FIG. 3 of the present invention. The terminal 120 may configure a PDU session modification complete message indicating completion of the PDU session modification procedure as an N1 SM NAS message and send it to the SMF 113.

In step 545, the base station 111 may send a response to step 540 to the SMF 113. This message includes an N2 SM message, and if the terminal 120 configures and sends a PDU session modification complete message as an N1 SM NAS message, an N1 SM NAS message may also be included.

Upon receiving the message in step 545, the AMF 112 may deliver the N2 SM message and the N1 SM NAS message contained in the message in step 545 to the SMF 113 in step 550.

In step 555, the SMF 113 may see the N2 SM message received in step 550 and perform an N4 session modification procedure with the UPF 117. At this time, the SMF 113 may transmit the N3 tunnel information of the base station side received from the base station 111 to the UPF 117, and may also transmit a packet forwarding rule for this. According to step 560, the SMF 113 may send a response message to step 550 to the AMF 112.

FIG. 6 is a diagram for a terminal through a policy update procedure according to an embodiment of the present invention to indicate to a terminal'DNS server information for finding an edge server to which the terminal should access in order to use the MEC service' or'For the terminal to use the MEC service. This is a diagram showing a method of updating'MEC configuration server information to be initially connected'.

The policy update procedure can be performed under the following conditions.

-Changing the location of the terminal 120: The PCF 114, which determines that the location of the terminal 120 has changed, may perform a policy update procedure in order to deliver valid MEC service related information to the current location of the terminal 120. That is, after determining the current location of the terminal 120, the PCF 114 sends the address of the DNS server 154 closest to the current location of the terminal 120 or the address of the MEC configuration server 153 to the terminal 120. Alternatively, it can be transferred to the MEC policy. Alternatively, the PCF 114 is a DNS server supporting the edge network in order to allow the terminal 120 to use an edge network that can be used at the current location of the terminal 120 after determining the current location of the terminal 120 The address of 154 or the address of the MEC configuration server 153 may be transmitted to the terminal 120 as URSP or MEC policy. Alternatively, when determining the address of the DNS server 154 or the address of the MEC configuration server 153 that can be used at the current location of the terminal 120, the PCF 114 considers the load state of the server to determine the optimal server. It is possible to determine which server address to provide to the terminal 120 by determining. The URSP or MEC policy configured by the PCF 114 may follow the URSP or MEC policy for MEC services handled in the embodiment according to FIG. 4 of the present invention.

-Change the subscription information of the terminal 120: If the terminal 120 is not using the MEC service and subscribes to additional services of the mobile communication service provider to use the MEC service, the mobile communication service provider sends the MEC to the terminal 120 It can be determined that necessary information must be provided to use the service. Accordingly, the PCF 114 can receive the subscription information updated from the UDR, and accordingly, information related to the MEC service to the terminal 120, that is, information of the DNS server 154 to which the terminal 120 must access in order to use the MEC service. Alternatively, it may be determined to provide information on the MEC configuration server 153. For this, the PCF 114 may configure a URSP or MEC policy, which may follow the URSP or MEC policy for MEC services handled in the embodiment according to FIG. 4 of the present invention. On the contrary, if the terminal 120 is using the MEC service and then cancels the additional service of the mobile communication service provider so that the MEC service is no longer used, the mobile communication service provider makes the terminal 120 no longer use the MEC service. In order to do so, it is necessary to update policy information set in the terminal 120. For example, an operation of deactivating MEC-related information among URSPs or deactivating MEC policy may be performed, and this may be known to the terminal 120 through updated URSP or policy information. For example, the traffic descriptor and route selection descriptor of the URSP for using the MEC service may be removed and transferred to the terminal 120. Alternatively, the MEC policy information may be filled with an empty value and sent to the terminal 120 to notify that it is deactivated.

- 3 ^rd party requests from: a operator to drive the application on the application providers or service providing MEC MEC service may request a set asking MEC provide services for a particular terminal or DNN. 5G system. This can be provided through a service level agreement or through an OAM system. The mobile communication service provider receiving this may determine to provide necessary information to use the MEC service to a terminal using a corresponding DNN or a specific terminal through a 5G system. Accordingly, the PCF 114 may update policy information on the terminal 120 to information capable of using the MEC service, configure this as URSP or MEC policy, and transmit it to the terminal 120. Alternatively, the OAM system may inform the PCF 114 of the DNS server 154 address or the MEC configuration server 153 address required to provide the MEC service to the specific terminal 120. The PCF 114, which has received information from the OAM system, provides information necessary for using the MEC service, that is, the URSP or MEC policy proposed in the embodiment according to FIG. 4 of the present invention to the terminal 120 You can do it.

In step 610, the PCF 114 determines a policy update according to the above conditions.

In step 620, in order to deliver the updated policy to the terminal 120, the PCF 114 may construct a policy NAS message called a MANAGE UE POLICY COMMAND message and transmit it to the AMF 112. The AMF 112 cannot interpret this message, and can determine which terminal 120 is a NAS message for policy to be transmitted.

If the terminal 120 is in the CM-IDLE state, the AMF 112 may paging the terminal in step 630 in order to deliver a policy NAS message to the terminal 120. If the terminal 120 is already in the CM-connected state 645, the AMF 112 may deliver the NAS message for policy received from the PCF 114 to the terminal 120 in step 650.

When the terminal 120 is in the CM-IDLE state, the AMF 112 may paging the terminal 120 according to step 630 in order to deliver a policy NAS message to the terminal 120. Upon receiving this, the terminal 1202 may transition to the CM-connected state by performing a service request procedure according to step 340 (645).

In step 650, the AMF 112 may transmit a policy NAS message received from the PCF 114, that is, MANAGE UE POLICY COMMAND, to the terminal 120 since the terminal 120 has transitioned to the CM-connected state. This message includes URSP or MEC policy information configured by the PCF 114 according to step 610. The information constituting the URSP or MEC policy in this embodiment may follow the embodiment of FIG. 4. The terminal 120 receiving the URSP or MEC policy through step 650 may apply this to the internal operation. A method of applying this by the terminal 120 may follow the embodiment of FIG. 4.

In step 660, the terminal 120 may construct a NAS message for policy called MANAGE UE POLICY COMPLETE and transmit it to the AMF 112 in order to send a response indicating that the policy information has been well applied to the PCF 114. The AMF 112 transfers this to the PCF 114 through step 670, and the PCF 114 knows that the terminal 120 has received and applied the policy well.

7 is a diagram showing the configuration of a terminal according to the present invention.

The terminal 120 according to an embodiment of the present invention may include a transmission/reception unit 720 and a control unit 710 for controlling the overall operation of the terminal 120. In addition, the transmission/reception unit 720 may include a transmission unit 721 and a reception unit 723.

The transceiving unit 720 may transmit and receive signals with other network entities.

The controller 710 may control the terminal 120 to perform any one of the above-described embodiments. Meanwhile, the control unit 710 and the transmission/reception unit 720 do not necessarily have to be implemented as separate modules, but may be implemented as a single component in the form of a single chip. In addition, the control unit 710 and the transmission/reception unit 720 may be electrically connected. And, for example, the control unit 710 may be a circuit, an application-specific circuit, or at least one processor. In addition, the operations of the terminal 120 may be realized by providing a memory device storing the corresponding program code in an arbitrary configuration unit in the terminal.

8 is a diagram illustrating the configuration of a network entity according to the present invention.

A network entity according to an embodiment of the present invention may include a transceiver 820 and a controller 810 that controls overall operations of the network entity. In addition, the transmission/reception unit 820 may include a transmission unit 821 and a reception unit 823.

The transmission/reception unit 820 may transmit and receive signals with other network entities.

The controller 810 may control the network entity to perform any one of the above-described embodiments. Meanwhile, the control unit 810 and the transmission/reception unit 820 do not necessarily have to be implemented as separate modules, but may be implemented as a single component in the form of a single chip. In addition, the control unit 810 and the transmission/reception unit 820 may be electrically connected. And, for example, the controller 810 may be a circuit, an application-specific circuit, or at least one processor. Further, the operations of the network entity can be realized by providing a memory device storing the corresponding program code in an arbitrary configuration unit in the network entity.

The network entity is a base station 111, AMF 112, SMF 113, UPF 116, PCF 114, UDM 117, UDR, edge server 151, configuration server 153, DNS server. It may be any one of (154).

It should be noted that the configuration diagrams illustrated in FIGS. 1 to 8, an exemplary diagram of a control/data signal transmission method, an exemplary diagram of an operation procedure, and a configuration diagram are not intended to limit the scope of the present disclosure. That is, it should not be construed that all components, entities, or steps of operation described in FIGS. 1 to 8 are essential components for the implementation of the disclosure, and including only some components does not impair the essence of the disclosure. Can be implemented within

The operations of the base station or the terminal described above can be realized by having a memory device storing the corresponding program code in an arbitrary configuration unit in the base station or terminal device. That is, the control unit of the base station or the terminal device may execute the above-described operations by reading and executing the program code stored in the memory device by the processor or CPU (Central Processing Unit).

Various components of an entity, a base station, or a terminal device, and a module described in this specification are hardware circuits, for example, a complementary metal oxide semiconductor-based logic circuit, and firmware. And, it may be operated using a hardware circuit such as a combination of software and/or hardware and firmware and/or software embedded in a machine-readable medium. As an example, various electrical structures and methods may be implemented using transistors, logic gates, and electrical circuits such as application-specific semiconductors.

Meanwhile, although specific embodiments have been described in the detailed description of the present disclosure, various modifications are possible without departing from the scope of the present disclosure. Therefore, the scope of the present disclosure is limited to the described embodiments and should not be defined, and should be determined by the scope of the claims and equivalents as well as the scope of the claims to be described later.

Claims (15)

In the communication method of a terminal in a wireless communication system,
transmitting a first message including information requesting use of edge computing service to a session management function (SMF); And
Receiving, from the SMF, a second message including information on a configuration server for receiving configuration information for the edge computing service,
The information on the setting server is set by a policy and charging function (PCF) based on information requesting the use of the edge computing service. The method of claim 1,
The first message, characterized in that the PDU session establishment message or a PDU session modification request message. The method of claim 1,
The information on the configuration server, characterized in that received through PCO (protocol configuration options). The method of claim 1,
And the information on the setting server includes information on the setting server determined based on at least one of information on the location of the terminal and information on loads of the setting servers. In the terminal of the wireless communication system,
A transceiver; And
A second message including information on a configuration server for transmitting a first message including information for requesting use of edge computing service to a session management function (SMF), and receiving configuration information for the edge computing service It includes a control unit receiving from the SMF,
The information on the setting server is set by a policy and charging function (PCF) based on information requesting the use of the edge computing service. The method of claim 5,
The first message is a terminal, characterized in that the PDU session establishment message or a PDU session modification request message. The method of claim 5,
The terminal, characterized in that the information on the configuration server is received through PCO (protocol configuration options). The method of claim 5,
The information on the setting server comprises information on the setting server determined based on at least one of information on a location of the terminal and information on loads of setting servers. In a communication method of a session management function (SMF) in a wireless communication system,
Receiving, from the terminal, a first message including information for requesting use of an edge computing service of the terminal;
Transmitting a second message for policy setting including information for requesting use of the edge computing service to a policy and charging function (PCF);
Receiving, from the PCF, a third message including information on a setting server for receiving setting information for the edge computing service set based on information requesting the use of the edge computing service; And
And transmitting a fourth message including information on the setting server to the terminal. The method of claim 9,
The first message, characterized in that the PDU session establishment message or a PDU session modification request message. The method of claim 9,
The fourth message, characterized in that the PCO (protocol configuration options) including information on the configuration server is included. The method of claim 9,
And the information on the setting server includes information on the setting server determined based on at least one of information on the location of the terminal and information on loads of the setting servers. In the SMF (session management function) of the wireless communication system,
A transceiver; And
A first message including information for requesting use of the edge computing service of the terminal is received from the terminal, and a second message for policy setting including information for requesting the use of the edge computing service is sent to PCF (policy and charging). function), and receiving a third message from the PCF including information on a setting server for receiving setting information for the edge computing service set based on information requesting the use of the edge computing service, SMF including a control unit for transmitting a fourth message including information on the setting server to the terminal. The method of claim 13,
The first message is a PDU session establishment message or a PDU session modification request message,
The fourth message, SMF, characterized in that the PCO (protocol configuration options) including information on the configuration server is included. The method of claim 13,
The information on the setting server includes information on the setting server determined based on at least one of information on a location of the terminal and information on loads of setting servers.

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