JP2020194988A - Communication control method and communication system - Google Patents

Abstract

To determine an appropriate access process based on an access type.SOLUTION: A communication control method executed by a communication control node (for example, NRF) for performing communication control in a communication system in which a slice, which is a virtual network, is logically generated on a network infrastructure includes: step (1) of acquiring an access type indicating an access method by a terminal to a network; and step (2) of determining an access process to slice components constituting the slice based on the acquired access type.SELECTED DRAWING: Figure 5

Description

The present invention relates to a communication control method and a communication system, and more specifically, a communication control node in a communication system in which a network slice (hereinafter abbreviated as "slice"), which is a virtual network, is logically generated on a network infrastructure. The communication control method executed by the above and the communication system.

A network system using conventional virtualization technology is a virtual network that is logically generated on a network infrastructure by virtually dividing hardware resources using the virtualization technology disclosed in Non-Patent Document 1. Generate a slice. Then, by allocating the service to the slice, the service can be provided by using the network of each independent slice. As a result, when slices are assigned to each service having various requirements, it is possible to easily satisfy the requirements of each service and reduce the signaling processing thereof.

Further, in the existing standardized architecture, the NSSF (Network Slice Selection Function), which is a slice selection device, is a slice component (for example, AMF (Access and Mobility Management Function)) that constitutes the above-mentioned slice based on the service requirements. ), SMF (Session Management Function), etc.).

Akihiro Nakao, Virtualization Node Project Virtualization Technology Aiming for a New Generation of Networks, [online], June 2010, National Institute of Information and Communications Technology, [Search March 16, 2015], Internet <http: / /www.nict.go.jp/publication/NICT-News/1006/01.html>

In the 5G (fifth generation network) era in recent years, not only the cellular system but also various access methods (access types) such as Wi-Fi (registered trademark) are used. However, the determination of access processing including the selection of slice components described above according to such various access types has not been studied much yet.

Therefore, an object of the present invention is to determine an appropriate access process based on the access type.

The communication control method according to the embodiment of the present invention is a communication control method executed by a communication control node that performs communication control in a communication system in which slices, which are virtual networks, are logically generated on a network infrastructure. The step includes a step of acquiring an access type indicating an access method to the network by the terminal, and a step of determining an access process to the slice component constituting the slice based on the acquired access type.

According to the above communication control method, the communication control node acquires an access type indicating an access method to the network by the terminal, and determines an access process to the slice component based on the acquired access type. This makes it possible to determine appropriate access processing based on the actual access type in situations where various access types can be used.

The above-mentioned "communication control node" includes, for example, AMF (Access and Mobility Management Function), SMF (Session Management Function), NRF (Network Repository Function) which is a dedicated node for determining access processing, and the like. The "slice component" includes, for example, AMF, SMF, UPF (User Plane Function), AUSF (Authentication Server Function), PCF (Policy Control Function) and the like. Further, the determined "access process" includes, for example, selection of a slice component according to the access type, and also includes inquiring the terminal for the access type when there is no slice component according to the access type. .. The "access type" is information indicating which access method the terminal has accessed.

According to the present invention, an appropriate access process can be determined based on the access type.

It is a block diagram of the communication system which concerns on 1st Embodiment. It is a flow chart of the process which concerns on 1st Embodiment. It is a block diagram of the communication system which concerns on 2nd Embodiment. It is a flow chart of the process which concerns on 2nd Embodiment. It is a flow chart which shows the detail of step 2 of FIG. It is a flow chart which shows the detail of step 7 of FIG. It is a figure which shows the hardware configuration example of the communication control node such as NRF.

Hereinafter, various embodiments of the present invention will be described with reference to the drawings. The first embodiment is an example in which the present invention is applied to a network registration process by a terminal (User Equipment, hereinafter referred to as “UE”), and the second embodiment is a PDU (Protocol Data Unit) based on a request from the UE. This is an example in which the present invention is applied to the session establishment process. In the description of the drawings, the same elements are designated by the same reference numerals, and duplicate description will be omitted.

[First Embodiment]
As shown in FIG. 1, the communication system 1a according to the first embodiment includes a terminal (UE) 10, a plurality of radio access networks (Radio Access Network (hereinafter referred to as “RAN”)) 20, an initial AMF30A, and a target. It includes AMF30B, NRF40, UDM (Unified Data Management) 50, NSSF60, AUSF (Authentication Server Function) 70, a plurality of SMF80s, and a plurality of UPFs (User Plane Function) 90s.

Of these, the plurality of RAN20s include wireless networks based on various communication methods, such as mobile communication networks related to the 3GPP standard including eNodeB corresponding to a base station, and wireless networks not conforming to the 3GPP standard (for example, Wi-Fi). Is included.

The initial AMF30A and the target AMF30B are nodes having a function (AMF function) for performing access management, mobility management, etc. of the UE 10 in the network, and among the above, the initial AMF30A is the default AMF for the UE 10. The target AMF30B is an AMF selected as an AMF to be accessed by the process according to the present invention described later.

The NRF 40 is a dedicated node having a function of determining the access process according to the present invention in the communication system 1a, and the UDM 50 is a node having a function of managing user (subscriber) information of the UE 10. The NSSF60 is a node having a function of selecting a slice, and the AUSF70 is a node having a function of executing an authentication process.

The SMF80 is a node having a function of managing U-Plane sessions, and the UPF90 is a node having a function of processing U-Plane traffic.

A slice, which is a virtual network logically generated on a network infrastructure, is configured to include the targets AMF30B, SMF80, and UPF90, and the set of nodes and lines constituting the slice is called NSI (Network Slice Instance). .. One AMF can be shared by multiple slices.

Hereinafter, an example in which the present invention is applied to the network registration process by the UE will be described with reference to FIG. Although the notation of "UE" is omitted in FIG. 2, the operation of "RAN" shown in FIG. 2 indicates message transmission from the UE and message transmission to the UE. Further, since the process of FIG. 2 is a process before the slice is created, the process by SMF80 and UPF90 is not included.

First, the Initial UE message is transmitted from the UE to the initial AMF via the RAN (step 1 in FIG. 2), and then a predetermined optional process is executed (step 2). Then, the initial AMF requests the UDM for the subscriber information related to the user (subscriber) of the UE (step 3), and receives the response from the UDM (step 4). Further, the initial AMF transmits a slice selection request to the NSSF (step 5), and receives the response from the NSSF (step 6).

Next, as a process according to the present invention, the initial AMF transmits an Nnrf_NF Discovery Request including an access type indicating an access method from the UE to the NRF in order to inquire the NRF about the target AMF to be accessed by the UE (step). 7). Prior to step 7, the initial AMF recognizes the access type from the UE in step 1 above, depending on which access method RAN the UE has accessed from. By automatically recognizing the access type in this way, it is not necessary to send an explicit notification (notification regarding the access type) from the UE. The initial AMF may recognize the access type by an explicit notification (notification regarding the access type) from the UE.

The NRF determines an appropriate target AMF according to the access type included in the Nnrf_NF Discovery Request, and responds the determined target AMF to the initial AMF by the Nnrf_NF Discovery Response (step 8). Here, the NRF may request the initial AMF to query the UE for another access type if there is no suitable target AMF for the access type. In this way, the NRF may not only determine the target AMF to be accessed, but may also request the UE to query another access type if there is no suitable target AMF. By determining the access destination (for example, the target AMF to be accessed) by a dedicated node called NRF, it is possible to stabilize the determination process and centrally manage information.

After that, the initial AMF performs the following redirection processing in order to change the destination of the message from the UE to the target AMF. Here, the first method of directly transmitting the Reroute message from the initial AMF shown in FIG. 2 (A) to the target AMF, and the second method of redirecting to the target AMF via the RAN shown in FIG. 2 (B). The method is exemplified.

According to the first method, the initial AMF sends a Reroute message directly to the target AMF (step 9A), and then sends and receives an N2 message between the target AMF and the RAN (steps 10A, 11A). Redirects the destination of the message from to the target AMF. The target AMF recognizes the access type from the UE depending on which access method RAN the N2 message is transmitted from in step 11A. By automatically recognizing the access type in this way, it is not necessary to send an explicit notification regarding the access type from, for example, the initial AMF. The target AMF may recognize the access type by the explicit notification of the access type included in the N2 message.

According to the second method, the initial AMF transmits a Reroute NAS message containing the information of the target AMF to the RAN (step 9B), and the Initial UE message from the UE is transmitted from the RAN to the target AMF again. (Step 10B), the destination of the message from the UE is redirected to the target AMF. The target AMF recognizes the access type from the UE depending on which access method RAN the Initial UE message is transmitted from in step 10B. The target AMF may also recognize the access type by the explicit notification of the access type included in the Initial UE message.

The target AMF then selects the appropriate AUSF based on the recognized access type (step 12). After that, a predetermined authentication process is performed between the selected AUSF, UE and UDM (step 13).

Then, after other processing related to network registration is executed (step 14), Registration Accept is transmitted from the initial AMF to the UE via RAN (step 15), and Registration Complete responds from the UE to the initial AMF via RAN. Is done (step 16). As a result, the network registration process of FIG. 2 is completed.

According to the first embodiment described above, by applying the present invention to the network registration process by the UE, the initial AMF selects an appropriate target AMF (target AMF to be accessed by the UE) according to the access type. it can. That is, an appropriate access process can be determined. Similarly, the target AMF can select the appropriate AUSF based on the recognized access type.

Along with this, a possible inconvenience when selecting an access destination node based on service requirements, for example, not based on the access type, that is, a node that is not suitable for the access type (for example, a node with excessive capacity) is selected. It is possible to prevent the inconvenience.

[Second Embodiment]
Next, in the second embodiment, an example in which the present invention is applied to the PDU session establishment process based on the request from the UE will be described. In the second embodiment, in order to explain the PDU session establishment process after the network registration process described in the first embodiment is completed, the communication system 1b according to the second embodiment shown in FIG. 3 has a PDU session establishment process. The components related to are shown.

As shown in FIG. 3, the communication system 1b includes a UE 10, a plurality of RAN20s, an AMF30, an NRF40, a UDM50, a plurality of SMF80s, a plurality of UPF90s, and a plurality of PCFs (Policy Control Function) 100. Consists of including.

The AMF30 here corresponds to the target AMF30B in the first embodiment, and the details will be described later. However, as the process according to the present invention, the AMF30 selects an appropriate SMF80 according to the access type from a plurality of SMF80s. The selected SMF80 selects an appropriate UPF90 according to the access type from the plurality of UPF90s, and selects an appropriate PCF100 according to the access type from the plurality of PCF100s.

Hereinafter, an example in which the present invention is applied to the PDU session establishment process based on the request from the UE will be described with reference to FIGS. 4 to 6.

First, a PDU Session Establishment Request is transmitted from the UE to the AMF via the RAN (step 1 in FIG. 4). At this time, the AMF recognizes the access type from the UE depending on which access method RAN the PDU Session Establishment Request is transmitted through. By automatically recognizing the access type in this way, it is not necessary to send an explicit notification about the access type from the UE. Note that the AMF may recognize the access type by the explicit notification of the access type included in the PDU Session Establishment Request.

Then, the AMF selects an appropriate SMF related to the PDU Session as follows (step 2). For example, as shown in FIG. 5, the AMF selects the appropriate SMF by contacting the NRF. That is, when the AMF transmits a Nnrf_NF Discovery_request including the access type recognized as described above (denoted as "Access Network Type" in FIG. 5) to the NRF (step 1 in FIG. 5), the NRF receives the Nnrf_NF. As a process for responding to the Discovery_request, an appropriate SMF corresponding to the access type is selected (step 2 in FIG. 5), and a Nnrf_NF Discovery_response containing the selected SMF information is responded to the AMF (step 3 in FIG. 5). Thereby, the AMF can select an appropriate SMF according to the access type. In step 2 of FIG. 4, the AMF may select the SMF according to the access type by itself, in addition to inquiring to the NRF.

The AMF then requests the establishment of a PDU Session by sending Namf_PDUSession_CreateSMContext to the selected SMF (step 3), the SMF obtains subscriber information by sending Nudm_SubscriberData_Get to UDM (step 4), and , A predetermined user authentication process (PDU Session authentication / authorization) prior to establishing the PDU session is executed (step 5).

The SMF recognizes the access type from, for example, the access type information included in the message received in step 3, or from the access type information included in the message (not shown) from AMF or the like. Then, the SMF selects an appropriate PCF according to the access type (step 6a). In the process of step 6a, the PCF may be selected by inquiring to the NRF or the PCF may be selected by the SMF itself, as in the above-mentioned step 2. After that, a predetermined process related to policy control is performed between the SMF and the selected PCF (steps 6b and 6c).

Next, the SMF selects an appropriate UPF according to the access type (step 7). For example, as shown in FIG. 6, the SMF selects the appropriate UPF by contacting the NRF. That is, when the SMF transmits a Nnrf_NF Discovery_request including the previously recognized access type (denoted as "Access Network Type" in FIG. 6) to the NRF (step 1 in FIG. 6), the NRF responds to the received Nnrf_NF Discovery_request. As an appropriate UPF according to the access type (step 2 in FIG. 6), an Nnrf_NF Discovery_response containing the selected UPF information is responded to the SMF (step 3 in FIG. 6). Thereby, the SMF can select an appropriate UPF according to the access type. In step 7 of FIG. 4, the SMF may select the UPF according to the access type by the SMF itself, in addition to inquiring to the NRF.

After that, predetermined processing related to policy control is performed between the SMF and the PCF (steps 8a and 8b), and the SMF sends an N4 Session Establishment / Modification Request to the selected UPF (step 9a). The response (N4 Session Establishment / Modification Response) from the UPF is received (step 9b).

Then, the SMF transmits an Nsmf_PDUSession_CreateSMContext Response to the AMF as a response to the PDU Session establishment request in step 3 (step 10).

The AMF makes a session establishment request by sending an N2 PDU Session Request to the RAN (step 11), and in response, a PDU Session is established between the RAN and the UE (step 12), and further from the RAN. By responding to the N2 PDU Session Request Ack to the AMF, the processing according to the session establishment request is completed (step 13). After that, a predetermined process including the first upstream data transmission from the UE is executed (step 14).

According to the second embodiment described above, by applying the present invention to the PDU session establishment process based on the request from the UE, the AMF can select an appropriate SMF according to the access type, and the SMF can access. Appropriate UPF and PCF can be selected according to the type. In this way, an appropriate access process can be determined.

Along with this, a possible inconvenience when selecting an access destination node based on service requirements, for example, not based on the access type, that is, a node that is not suitable for the access type (for example, a node with excessive capacity) is selected. It is possible to prevent the inconvenience.

The block diagram used in the description of the above embodiment shows a block of functional units. These functional blocks (components) are realized by any combination of hardware and / or software. Further, the means for realizing each functional block is not particularly limited. That is, each functional block may be realized by one physically and / or logically coupled device, or directly and / or indirectly by two or more physically and / or logically separated devices. (For example, wired and / or wireless) may be connected and realized by these plurality of devices.

For example, the communication control node (nodes such as NRF40, AMF30, SMF80), the terminal (UE) 10, and the like in the above embodiment may function as a computer that performs the above-mentioned processing. As an example, FIG. 7 shows an example of the hardware configuration of the UE 10, but the same applies to other devices / nodes. As shown in FIG. 7, the UE 10 may be physically configured as a computer device including a processor 1001, a memory 1002, a storage 1003, a communication device 1004, an input device 1005, an output device 1006, a bus 1007, and the like.

In the following description, the word "device" can be read as a circuit, device, unit, or the like. The hardware configuration of the terminal 10 may be configured to include one or more of the devices shown in the figure, or may be configured not to include some of the devices.

For each function in the terminal 10, by loading predetermined software (program) on hardware such as the processor 1001 and the memory 1002, the processor 1001 performs an calculation, and communication by the communication device 1004 and the memory 1002 and the storage 1003 It is realized by controlling the reading and / or writing of data.

Processor 1001 operates, for example, an operating system to control the entire computer. The processor 1001 may be composed of a central processing unit (CPU) including an interface with a peripheral device, a control device, an arithmetic unit, a register, and the like. For example, each functional unit of the terminal 10 may be realized including the processor 1001.

Further, the processor 1001 reads a program (program code), a software module, and data from the storage 1003 and / or the communication device 1004 into the memory 1002, and executes various processes according to these. As the program, a program that causes a computer to execute at least a part of the operations described in the above-described embodiment is used. For example, each functional unit of the terminal 10 may be stored in the memory 1002 and realized by a control program operating on the processor 1001, and other functional blocks may be realized in the same manner. Although it has been described that the various processes described above are executed by one processor 1001, they may be executed simultaneously or sequentially by two or more processors 1001. Processor 1001 may be mounted on one or more chips. The program may be transmitted from the network via a telecommunication line.

The memory 1002 is a computer-readable recording medium, and is composed of at least one such as a ROM (Read Only Memory), an EPROM (Erasable Programmable ROM), an EEPROM (Electrically Erasable Programmable ROM), and a RAM (Random Access Memory). May be done. The memory 1002 may be referred to as a register, a cache, a main memory (main storage device), or the like. The memory 1002 can store a program (program code), a software module, or the like that can be executed to carry out the method according to the embodiment of the present invention.

The storage 1003 is a computer-readable recording medium, for example, an optical disk such as a CD-ROM (Compact Disc ROM), a hard disk drive, a flexible disk, a magneto-optical disk (for example, a compact disk, a digital versatile disk, a Blu-ray). It may consist of at least one (registered trademark) disk), smart card, flash memory (eg, card, stick, key drive), floppy (registered trademark) disk, magnetic strip, and the like. The storage 1003 may be referred to as an auxiliary storage device. The storage medium described above may be, for example, a database, server or other suitable medium containing memory 1002 and / or storage 1003.

The communication device 1004 is hardware (transmission / reception device) for performing communication between computers via a wired and / or wireless network, and is also referred to as, for example, a network device, a network controller, a network card, a communication module, or the like. For example, each functional unit of the terminal 10 described above may be realized by including the communication device 1004.

The input device 1005 is an input device (for example, a keyboard, a mouse, a microphone, a switch, a button, a sensor, etc.) that receives an input from the outside. The output device 1006 is an output device (for example, a display, a speaker, an LED lamp, etc.) that outputs to the outside. The input device 1005 and the output device 1006 may have an integrated configuration (for example, a touch panel).

Further, each device such as the processor 1001 and the memory 1002 is connected by a bus 1007 for communicating information. Bus 1007 may be composed of a single bus, or may be composed of different buses between devices.

Further, the terminal 10 includes hardware such as a microprocessor, a digital signal processor (DSP: Digital Signal Processor), an ASIC (Application Specific Integrated Circuit), a PLD (Programmable Logic Device), and an FPGA (Field Programmable Gate Array). The hardware may implement some or all of each functional block. For example, processor 1001 may be implemented on at least one of these hardware.

Although the present embodiment has been described in detail above, it is clear to those skilled in the art that the present embodiment is not limited to the embodiment described in the present specification. This embodiment can be implemented as an amended or modified mode without departing from the gist and scope of the present invention determined by the description of the claims. Therefore, the description of the present specification is for the purpose of illustration and does not have any limiting meaning to the present embodiment.

The order of the processing procedures, sequences, flowcharts, and the like of each aspect / embodiment described in the present specification may be changed as long as there is no contradiction. For example, the methods described herein present elements of various steps in an exemplary order, and are not limited to the particular order presented.

The input / output information and the like may be stored in a specific location (for example, memory), or may be managed by a management table. Input / output information and the like can be overwritten, updated, or added. The output information etc. may be deleted. The input information and the like may be transmitted to another device.

The determination may be made by a value represented by 1 bit (0 or 1), by a boolean value (Boolean: true or false), or by comparing numerical values (for example, a predetermined value). It may be done by comparison with the value).

Each aspect / embodiment described in the present specification may be used alone, in combination, or may be switched and used according to the execution. Further, the notification of predetermined information (for example, the notification of "being X") is not limited to the explicit one, but is performed implicitly (for example, the notification of the predetermined information is not performed). May be good.

Software is an instruction, instruction set, code, code segment, program code, program, subprogram, software module, whether called software, firmware, middleware, microcode, hardware description language, or another name. , Applications, software applications, software packages, routines, subroutines, objects, executables, execution threads, procedures, features, etc. should be broadly interpreted.

Further, software, instructions, and the like may be transmitted and received via a transmission medium. For example, the software uses wired technology such as coaxial cable, fiber optic cable, twist pair and digital subscriber line (DSL) and / or wireless technology such as infrared, wireless and microwave to websites, servers, or other When transmitted from a remote source, these wired and / or wireless technologies are included within the definition of transmission medium.

The information, signals, etc. described herein may be represented using any of a variety of different techniques. For example, data, instructions, commands, information, signals, bits, symbols, chips, etc. that may be referred to throughout the above description are voltages, currents, electromagnetic waves, magnetic fields or magnetic particles, light fields or photons, or any of these. It may be represented by a combination of.

Further, the information, parameters, etc. described in the present specification may be represented by an absolute value, a relative value from a predetermined value, or another corresponding information. ..

Mobile communication terminals may be subscriber stations, mobile units, subscriber units, wireless units, remote units, mobile devices, wireless devices, wireless communication devices, remote devices, mobile subscriber stations, access terminals, mobile terminals, etc. It may also be referred to as a wireless terminal, remote terminal, handset, user agent, mobile client, client, or some other suitable term.

The terms "determining" and "determining" as used herein may include a wide variety of actions. "Judgment" and "decision" are, for example, judgment, calculation, computing, processing, deriving, investigating, looking up (for example, table). , Searching in a database or another data structure), ascertaining can be considered as a "judgment" or "decision". Also, "judgment" and "decision" are receiving (for example, receiving information), transmitting (for example, transmitting information), input (input), output (output), and access. (Accessing) (for example, accessing data in memory) may be regarded as "judgment" or "decision". In addition, "judgment" and "decision" mean that "resolving", "selecting", "choosing", "establishing", "comparing", etc. are regarded as "judgment" and "decision". Can include. That is, "judgment" and "decision" may include that some action is regarded as "judgment" and "decision".

The phrase "based on" as used herein does not mean "based on" unless otherwise stated. In other words, the statement "based on" means both "based only" and "at least based on".

In the use of designations such as "first" and "second" herein, any reference to the elements does not generally limit the quantity or order of those elements. These designations can be used herein as a convenient way to distinguish between two or more elements. Thus, references to the first and second elements do not mean that only two elements can be adopted there, or that the first element must somehow precede the second element.

As long as "include", "including", and variations thereof are used within the scope of the present specification or claims, these terms are similar to the term "comprising". Is intended to be inclusive. Furthermore, the term "or" as used herein or in the claims is intended not to be an exclusive OR.

In the present specification, a plurality of devices shall be included unless the device has only one device apparently in the context or technically. In the whole of the present disclosure, the plural shall be included unless the context clearly indicates the singular.

1a, 1b ... Communication system, 10 ... Terminal (UE), 20 ... RAN, 30 ... AMF, 30A ... Initial AMF, 30B ... Target AMF, 40 ... NRF, 50 ... UDM, 60 ... NSSF, 70 ... AUSF, 80 ... SMF, 90 ... UPF, 100 ... PCF, 1001 ... Processor, 1002 ... Memory, 1003 ... Storage, 1004 ... Communication device, 1005 ... Input device, 1006 ... Output device, 1007 ... Bus.

Claims (6)

A communication control method executed by a communication control node that controls communication in a communication system in which slices, which are virtual networks, are logically generated on the network infrastructure.
Steps to get the access type that indicates how the terminal accesses the network,
A step of determining access processing to the slice component constituting the slice based on the acquired access type, and
Communication control method including. In the acquisition step, the communication control node acquires the access type by identifying the type of network accessed by the terminal.
The communication control method according to claim 1. The communication control node includes an NRF (Network Repository Function), which is a dedicated node for determining the access process.
The communication control method according to claim 1 or 2. The NRF receives an inquiry of the access type and the SMF (session management function) to be accessed from the AMF (access and mobility management function) included in the communication system, and receives the inquiry of the access type. The SMF to be accessed is determined based on the above, and the determined SMF to be accessed is responded to the AMF.
The communication control method according to claim 3. The NRF receives an inquiry of the access type and the UPF (user plane function) to be accessed from the SMF (session management function) included in the communication system, and based on the access type, the NRF receives the inquiry. The UPF to be accessed is determined, and the determined UPF to be accessed is responded to the SMF.
The communication control method according to claim 3 or 4. A communication system in which slices, which are virtual networks, are logically generated on the network infrastructure.
A communication control node that acquires an access type indicating an access method to the network by a terminal and determines access processing to the slice components constituting the slice based on the acquired access type.
Communication system including.

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