Control of closed network using network slice

Abstract

The present invention implements a closed network that is less susceptible to trouble. In the present invention, a communication system includes a base system (43) and a core network system (41). The base system controls communication performed by a terminal (S105), and relays, to another system disposed in a base, data acquired from the terminal on the basis of the control (S106). The core network system controls communication performed by the terminal (S108). In response to a request, transmitted from the terminal via a base antenna included in the base system, for connection to a network slice of a closed network, the base system causes the base system to control communication performed by the terminal (S104), and in response to a request, transmitted from the terminal via the base antenna, for connection to another network slice, the base system causes the core network system to control communication of the terminal (S107).

Description

Controlling closed networks using network slices

[0001] The present disclosure relates to control of a private network using network slices.

[0002] There is a technology that uses network slices, which virtually divide (slice) a network, as a closed network that is resistant to external intrusions.

[0003] "16.3.4.2 AMF and NW Slice Selection" of 3GPP (registered trademark) TS 38.300 V17.1.0 (2022-06) discloses that the RAN selects an AMF according to the NSSAI etc. provided by the UE.

[0004] The function that controls the network slice (e.g., AMF) is usually located in the data center of the mobile communication network itself, not in a base included in the private network. Therefore, if an abnormality occurs in the communication between the data center and a base in the private network or in the data center itself, the private network will become unusable even at the base.

[0005] The present disclosure has been made in consideration of the above-mentioned problems, and one of its purposes is to provide a technology for realizing a closed network that is less susceptible to problems such as equipment failure.

[0006] In order to solve the above-mentioned problems, the communication system according to the present disclosure includes a base system disposed at a base and including an antenna and one or more processors, and a core network system connected to the base system and including one or more processors. Base request processing, base control processing, and base relay processing are executed by at least one of the one or more processors included in the base system. The base control processing controls communication by the terminal. The base relay processing communicates with the terminal based on the control, and relays data acquired from the terminal to another system disposed at the base. At least one of the one or more processors included in the core network system executes a core control processing that controls communication by the terminal. The base request processing requests the base system to perform the base control processing for communication by the terminal in response to a request for connection to a network slice of a predetermined closed network transmitted from the terminal via the base antenna, and requests the core network system to perform the core control processing for communication by the terminal in a network slice different from the network slice of the predetermined closed network in response to a request for connection to a network slice different from the network slice of the predetermined closed network transmitted from the terminal via the base antenna. In response to the request for the base control process by the base request process, the base relay process is started.

[0007] In addition, in the communication control method according to the present disclosure, at least one of one or more processors included in a base system located at a base controls communication by a terminal, communicates with the terminal based on the control, and relays data acquired from the terminal to another system located at the base, and at least one of one or more processors included in a core network system controls communication by the terminal. At least one of the one or more processors included in the base system controls communication by the terminal in response to a request for connection from the terminal to a network slice of a predetermined closed network transmitted from the terminal via a base antenna included in the base system, and at least one of the one or more processors included in the core network system controls communication by the terminal in a network slice different from the network slice of the predetermined closed network in response to a request for connection from the terminal transmitted from the terminal via the base antenna. When control of communication by at least one of the one or more processors included in the base system is started, relaying between the terminal and the other system is started via the base antenna.

[0008] 1 is a diagram illustrating an example of a communication system according to an embodiment of the present disclosure. FIG. 2 is a diagram illustrating an overview of a communication system according to the embodiment. FIG. 3 is a diagram illustrating an example of associations between elements established in a communication system according to the embodiment. FIG. 4 is a flow diagram illustrating an overview of processing in a communication system when a terminal connects to a mobile communication network. FIG. 5 is a diagram illustrating an example of a communication route when a terminal accesses an external network via an antenna at a base. FIG. 6 is a diagram illustrating an example of a communication route when a terminal accesses a closed network via an antenna at a base. FIG. 7 is a diagram illustrating an example of a communication route when a terminal accesses an external network via an antenna outside the base. FIG. 8 is a diagram illustrating another example of a communication route when a terminal accesses a closed network via an antenna outside the base.

[0009] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the drawings.

[0010] 1 and 2 are diagrams illustrating an example of a communication system 1 according to an embodiment of the present disclosure. FIG. 1 is a diagram focusing on the locations of facilities included in the communication system 1. The communication system 1 provides a mobile communication network. Furthermore, a specific network slice of the provided mobile communication network provides a closed network that connects to a system at a base. Hereinafter, when simply referred to as a "closed network," it corresponds to this specific network slice.

[0011] As shown in Fig. 1, the communication system 1 includes, as its facilities, a central data center 11, a regional data center 12, an edge data center 13, base station facilities 14, and base station facilities 16. The base station facilities 16 are facilities that perform mobile wireless communication with terminals 20. The base station facilities 16 include an antenna 17 and an RU (Radio Unit) described below. The base station facilities 14 include an antenna 15, an RU (not shown), and multiple servers 31. The base station facilities 14 correspond to bases such as hospital facilities or office buildings, for example.

[0012] The terminal 20 is called UE (User Equipment). The terminal 20 is a mobile terminal such as a smartphone, and can connect to a mobile communication network via wireless communication. Some terminals 20 are configured to access a network slice of a closed network, while others are not.

[0013] The central data center 11, the regional data centers 12, and the edge data centers 13 are collectively called a data center group. For example, there are several central data centers 11, several tens of regional data centers 12, and several thousand to several tens of thousands of edge data centers 13.

[0014] For example, the central data center 11 is distributed throughout the area (e.g., Japan) covered by the communication system 1. The regional data centers 12 are distributed throughout the area covered by the communication system 1. For example, if the area covered by the communication system 1 is the entirety of Japan, one or two regional data centers 12 may be located in each prefecture.

[0015] Each edge data center 13 is capable of communicating with the base station equipment 16. One edge data center 13 may be capable of communicating with a plurality of base station equipment 16.

[0016] In this embodiment, for example, the central data center 11, the regional data centers 12, and the edge data centers 13 are capable of communicating with each other via a communication network. Furthermore, the central data centers 11, the regional data centers 12, and the edge data centers 13 are also capable of communicating with each other via the communication network.

[0017] In the central data center 11, the regional data center 12, and the edge data center 13 according to this embodiment, a plurality of servers 30 are arranged.

[0018] Each of the multiple servers 30 includes one or multiple processors 30 a, a storage unit 30 b, and a communication unit 30 c. The multiple servers 30 located in the central data center 11, the regional data centers 12, and the edge data centers 13 provide a type of cloud infrastructure using a virtualized application execution environment, which will be described later.

[0019] Each of the plurality of servers 31 arranged in the base facility 14 includes one or more processors 31 a, a storage unit 31 b, and a communication unit 31 c. A virtualized application execution environment is implemented on the plurality of servers 31.

[0020] The processors 30a and 31a are program-controlled devices such as microprocessors that operate according to a program. The storage unit 30b is, for example, a storage element such as a ROM or RAM, a solid-state drive (SSD), or a hard disk drive (HDD). The storage units 30b and 31b store programs executed by the processors 30a and 31a. The communication units 30c and 31c are, for example, communication interfaces such as a network interface controller (NIC) or a wireless local area network (LAN) module. The communication units 30c and 31c exchange data with other servers and network devices. The communication units 30c and 31c may constitute part of a software-defined networking (SDN).

[0021] In this embodiment, a container-type virtualized application execution environment such as Docker (registered trademark) is installed on the servers 30 located in the central data center 11, the regional data centers 12, and the edge data center 13. The container-type virtualized application execution environment can deploy and run containers on these servers 30. A cluster consisting of one or more containers generated by such virtualization technology may be constructed on these servers 30. For example, a Kubernetes cluster managed by a container management tool such as Kubernetes (registered trademark) may be constructed. Then, a processor on the constructed cluster may execute a container-type application.

[0022] A container-based virtualized application execution environment and a container management tool may also be installed on the server 31. A cluster made up of one or more containers generated by such virtualization technology may be constructed on these servers 31.

[0023] 2 is a diagram for explaining the communication system 1 according to the present embodiment in brief, and in particular, the internal functions and processes of the communication system 1.

[0024] From the viewpoint of functionality and processing, the communication system 1 includes a core network system 41, a plurality of base station systems 42, and a base station system 43. The core network system 41, the base station systems 42, and the base station systems 43 are connected by a software-defined network (SDN) 51 and are capable of communicating with each other.

[0025] Each of the base station systems 42 includes a DU (Distributed Unit) 45 and a CU (Central Unit) 46. The core network system 41 includes multiple AMFs (Access and Mobility Management Functions) 47, multiple SMFs (Session Management Functions) 48, and multiple UPFs (User Plane Functions) 49. Each of the base station systems 42 includes an RU (Radio Unit) 44 and an antenna 17, and the RU 44 is a radio transmitting / receiving device that communicates with terminals 20. The RU 44 is mainly located in the base station equipment 16 and the central equipment 14, and communicates with the DU 45 of the same base station system 42. The central system 43 includes an RU 44, a DU 45, a CU 46, an AMF 47, an SMF 48, and a UPF 49. The central system 43 includes an RU 44 and an antenna 15 located at the central station, and the RU 44 is a radio transmitting / receiving device. This RU 44 communicates with a DU 45 in the same base system 43 .

[0026] The functions and processes of the core network system 41 and the base station system 42 may be implemented by one or more processors 30a included in one or more servers 30 executing programs (execution instructions) stored in the storage unit 30b. Note that a so-called container management tool may be used to manage the storage of programs (program modules) corresponding to each unit in the storage unit 30b and the execution of the processors 30a.

[0027] The functions and processes of the base system 43 may be implemented by one or more processors 31a included in one or more servers 31 executing programs (execution instructions) stored in the storage unit 31b. A so-called container management tool may manage the storage of programs (program modules) corresponding to each unit in the storage unit 31b and the execution of the processors 31a.

[0028] The DU 45 and CU 46 included in the base station system 42 and the base station system 43 are the DU and CU in 5G, respectively. The DU 45 processes an uplink signal acquired from the terminal 20 via the RU 44. The DU 45 acquires the uplink signal from the terminal 20 via the RU 44. The DU 45 also converts downlink data destined for the terminal 20 into a downlink signal for wireless transmission. The downlink signal is wirelessly transmitted from the RU 44.

[0029] The DU45 may include, for example, the functions of the PHY-High layer, MAC layer, and RLC layer in so-called 4G and 5G. The functions of the CU46 may include the functions of the PDCP layer and PRC / SDAP layer. The boundary between the functional layers of the DU45 and the CU46 may be different from that in the above example. The MAC layer performs tasks such as allocating radio resources, and the RLC layer performs tasks such as retransmission control.

[0030] The upstream signal is a signal input from the terminal 20 to the DU 45, and the downstream signal is a signal output from the DU 45 to the terminal 20. Data output from the DU 45 to the core network system 41 (e.g., the AMF 47 or the UPF 49) is referred to as upstream data, and data output from the core network system 41 to the DU 45 is referred to as downstream data.

[0031] The DUs 45 and CUs 46 included in the base station system 42 are mainly located in the edge data center 13. More specifically, these DUs 45 and CUs 46 may be implemented by one or more servers 30 located in the edge data center 13. A certain edge data center 13 may be located with multiple sets, each including one or more DUs 45 and one CU 46, and the multiple DUs 45 included in a set may be connected to the CU 46 of that set. Note that the DUs 45 and CUs 46 included in the base station system 42 may be located in a data center different from the edge data center 13.

[0032] The DU 45 and CU 46 included in the base system 43 may be implemented by one or more servers 31 located in the base facility 14.

[0033] Here, the DU 45 and CU 46 included in the base station system 42 and the base system 43 may be a virtual distributed unit (vDU) and a virtual central unit (vCU), respectively, in 4G. Some of the DU 45 and CU 46 may be implemented in the central data center 11 or the regional data center 12, rather than in the edge data center 13. The RU 44, DU 45, and CU 46 constitute a radio access network (RAN).

[0034] The RAN is a computer system equipped with an antenna, equivalent to an eNB (eNodeB) in a fourth-generation mobile communication system (hereinafter referred to as 4G) or a gNB (NR base station) in a fifth-generation mobile communication system (hereinafter referred to as 5G). The core network system 41 and the RAN cooperate with each other to realize a mobile communication network that communicates with the terminal 20.

[0035] The CU 46 included in the base system 43 executes a base request process using at least one of one or more processors 31a. In the base request process, the CU 46 requests control of communication from the AMF 47 corresponding to the network slice to which the terminal 20 requests connection. The CU 46 included in the base station system 42 executes an external request process using at least one of one or more processors 30a. Details of these processes will be described later.

[0036] The core network system 41 is a system equivalent to an EPC (Evolved Packet Core) in 4G or a 5G core (5GC) in 5G. The core network system 41 according to this embodiment is implemented mainly by a plurality of servers 30 arranged in a central data center 11 and a regional data center 12. As described above, the core network system 41 includes NFs such as a plurality of AMFs 46, a plurality of SMFs 48, and a plurality of UPFs 49 as software functional units. The core network system 41 is connected to an external network such as the Internet.

[0037] The AMF 47 accepts a connection request from the terminal 20 via the gNB and authenticates the terminal 20. When the terminal 20 is authenticated, the AMF 47 registers information (information indicating the location of the terminal 20) for enabling an incoming call to the terminal 20 in an internal database. When the terminal 20 is authenticated after the AMF 47 accepts the connection request, the SMF 48 establishes a communication path (PDU session) between the terminal 20 and an appropriate UPF 49. The AMF 47 and SMF 48 included in the core network system 41 constitute a core control unit that controls communication between the terminal 20 and the mobile communication network.

[0038] For example, when a connection to a network slice of a closed network is requested, the SMF 48 may establish a communication path between the UPF 49 included in the base system 43 and the terminal 20. When a connection to a network slice different from that of the closed network is requested, the SMF 48 may establish a communication path between the UPF 49 included in the core network system 41 and the terminal 20.

[0039] The core control unit included in the core network system 41 executes core control processing using at least one of the one or more processors 30a. In the core control processing, the core control unit controls communication by the terminal 20.

[0040] The UPF 49 included in the core network system 41 executes a core relay process of relaying communication data between the terminal 20 and an external network such as the Internet, using at least one of the one or more processors 30a. The UPF 49 starts communication with the terminal 20 as a core relay process after the core control process accepts a request to control communication of the terminal 20 in a network slice of the closed network (strictly speaking, after a communication path between the terminal 20 and the UPF 49 is established).

[0041] The AMF 47, SMF 48, and UPF 49 included in the base system 43 have the same functions as those of the core network system 41, but are located in the base equipment 14. Furthermore, these AMF 47, SMF 48, and UPF 49 are capable of processing network slices of a closed network. Depending on the application of the network slice, the AMF 47 included in the base system 43 can process network slices that are different from those of a closed network instead of the AMF 47 of the core network system 41. The AMF 47 and SMF 48 included in the base system 43 constitute a base control unit that controls communication between the terminal 20 and the closed network of the mobile communication network.

[0042] The base control unit executes a base control process for controlling communication by the terminal 20 using at least one of the one or more processors 31a.

[0043] Here, the CU 46 included in the base system 43 selects either the base control process or the core control process (AMF 47 of the core network system 41 and the base system 43) in the base request process and requests control of communication. More specifically, in the base request process, when the CU 46 receives a request from the terminal 20 to connect to a network slice of the closed network via the antenna 15 of the base, it requests the base control process to control the communication by the terminal 20. On the other hand, when the CU 46 receives a request from the terminal 20 via the antenna 15 to connect to a network slice different from the network slice of the closed network, it requests the core control process to control the communication of the terminal 20 in the network slice different from the network slice of the closed network.

[0044] On the other hand, the CU46 included in the base station system 42 requests control of communication from the core control process (strictly speaking, the AMF47 of the core network system 41) whether the request is for connection to a network slice of the closed network or a different network slice. Here, the CU46 may change the type of AMF47 to be requested for control depending on the network slice to which the terminal 20 requests connection, or may request control from an AMF47 of the same type.

[0045] Furthermore, the UPF 49 included in the base system 43 executes base relay processing using at least one of the one or more processors 31 a. In the base relay processing, the UPF 49 communicates with the terminal 20 under control of the base control processing, and relays data acquired from the terminal 20 to other systems (other systems connected to the closed network) located at the base. After the base control unit receives a request for communication control from the CU 46 (strictly speaking, after a communication path between the terminal 20 and the UPF 49 is established), in the base relay processing, the UPF 49 starts communication with the terminal 20 via the antenna 15 at the base.

[0046] The other systems include, for example, at least one of a voice communication system 61, a nurse call system 62, and a database system 63. The base system 43 may be connected to a system different from those shown in Fig. 2, or may not be connected to some of the other systems shown in Fig. 2. Some of the other systems shown in Fig. 2 may not exist.

[0047] The voice communication system 61 is a system that enables calls between external telephone devices and internal telephone devices (e.g., terminal 20) via telephone lines, or calls between internal telephone devices. The voice communication system 61 may include, for example, a Session Initiation Protocol (SIP) server. The functions and processing of the voice communication system 61 and the nurse call system 62 may be implemented by one or more processors 31a included in one or more servers 31 executing programs stored in storage units 31b. The voice communication system 61 and the nurse call system 62 may also be implemented in a server different from the server 31 and connected via a base LAN.

[0048] The database system 63 is implemented by a computer and is a system including a database. The database system 63 may be, for example, a medical record management system in a hospital. In Fig. 2, the database system 63 is connected to the UPF 49 via a secure base LAN. The database system 63 may be implemented by one or more servers 31, or may be connected to the UPF 49 without via a LAN.

[0049] When the terminal 20 communicates data with another system via the antenna 15 of the base facility 14, the communication goes through the UPF 49 of the base system 43, and the core network system 41 is not used. This is called a local breakout. With a local breakout, the terminal 20 can communicate efficiently with other systems at the base. Furthermore, if the AMF 47 and SMF 48 of the core network system 41 are not used, communication over the closed network at the base can be maintained even if an abnormality occurs in the core network system 41 or in communication between the base system 43 and the core network system 41. This makes it possible to prevent the closed network connected to the system at the base from being stopped due to a failure.

[0050] Here, a method for implementing functions of the communication system 1 according to this embodiment will be described. The communication system 1 is composed of multiple functional units (e.g., network functions (NFs)) to realize network services. In this embodiment, the functional units are implemented as NFs realized by virtualization technology. NFs realized by virtualization technology are called VNFs (Virtualized Network Functions). It does not matter what virtualization technology is used for virtualization. For example, in this description, a CNF (Containerized Network Function) realized by container-type virtualization technology is also included in the VNF. In this embodiment, a network service will be described as being implemented by one or more CNFs. Furthermore, the functional units according to this embodiment may correspond to network nodes.

[0051] 3 is a diagram schematically illustrating an example of associations between elements established in the communication system 1 in this embodiment. The symbols M and N shown in FIG. 3 represent any integers equal to or greater than 1, and indicate the relationship between the numbers of elements connected by a link. When both ends of a link are a combination of M and N, the elements connected by the link have a many-to-many relationship, and when both ends of a link are a combination of 1 and N or a combination of 1 and M, the elements connected by the link have a one-to-many relationship.

[0052] As shown in FIG. 3, the network service (NS), network function (NF), CNFC (Containerized Network Function Component), pod, and container have a hierarchical structure.

[0053] The NS corresponds to, for example, a network service configured from a plurality of NFs. Here, the NS may correspond to, for example, a granular element such as 5GC, EPC, 5G RAN (gNB), or 4G RAN (eNB).

[0054] In 5G, the NFs correspond to elements with granularity such as the DU 45, CU 46, and UPF 49. Furthermore, the NFs correspond to elements with granularity such as the AMF 47, SMF, and UPF 49. Furthermore, in 4G, the NFs correspond to elements with granularity such as a Mobility Management Entity (MME), a Home Subscriber Server (HSS), a Serving Gateway (S-GW), a vDU, and a vCU. In this embodiment, for example, one NS includes one or more NFs. That is, one or more NFs are subordinate to one NS.

[0055] A CNFC corresponds to a granularity element such as DU mgmt or DU Processing. A CNFC may be a microservice deployed on the server 30 as one or more containers. For example, a certain CNFC may be a microservice that provides some of the functions of the DU 45, CU 46, etc. Also, a certain CNFC may be a microservice that provides some of the functions of the UPF 49, AMF 47, SMF, etc. In this embodiment, for example, one NF includes one or more CNFCs. In other words, one or more CNFCs are subordinate to one NF.

[0056] A pod is the smallest unit for managing a Docker container in Kubernetes. In this embodiment, for example, one CNFC includes one or more pods. In other words, one CNFC has one or more pods under its control.

[0057] In this embodiment, for example, one pod includes one or more containers, that is, one or more containers are subordinate to one pod.

[0058] Also, as shown in Figure 3, network slices (NSIs) and network slice subnet instances (NSSIs) have a hierarchical structure.

[0059] The NSI can also be considered an end-to-end virtual circuit spanning multiple domains (e.g., from the RAN to the core network system 41). The NSI may be a slice for high-speed, large-capacity communication (e.g., for enhanced Mobile Broadband (eMBB)), a slice for high-reliability and low-latency communication (e.g., for Ultra-Reliable and Low Latency Communications (URLLC)), or a slice for connecting a large number of terminals (e.g., for massive Machine Type Communication (mMTC)). The NSSI can also be considered a virtual circuit of a single domain obtained by dividing the NSI. The NSSI may be a slice of the RAN domain, a slice of the Mobile Back Haul (MBH) domain, or a slice of the core network domain.

[0060] In this embodiment, for example, one NSI includes one or more NSSIs. That is, one or more NSSIs are subordinate to one NSI. Note that in this embodiment, multiple NSIs may share the same NSSI.

[0061] Furthermore, as shown in FIG. 3, NSSIs and NSs generally have a many-to-many relationship.

[0062] Furthermore, in this embodiment, for example, one NF can belong to one or more network slices. Specifically, for example, one NF can be configured with NSSAI (Network Slice Selection Assistance Information) including one or more S-NSSAI (Sub Network Slice Selection Assist Information). Here, S-NSSAI is one piece of information for identifying a network slice. Note that at least some NFs may not belong to a network slice.

[0063] Next, the operation when the terminal 20 connects to the mobile communication network will be described. Fig. 4 is a flow diagram illustrating an overview of the processing of the communication system 1 when the terminal 20 connects to the mobile communication network. Fig. 4 is a diagram illustrating the processing when the terminal 20 starts communication via the antenna 15 located in the base facility 14. Note that, since the specific procedure when the terminal 20 connects to the mobile communication network is publicly known, Fig. 4 omits a description of processing that is not particularly related to connecting to a network slice of a closed network.

[0064] Furthermore, a list of network slices supported by the base station including the CU 46 is registered in advance in the CU 46 included in the base station system 43 and the base station system 42, and each of the CUs 46 is pre-enabled to communicate with the AMF 47 corresponding to the network slice it supports. Note that the AMF 47 corresponding to the network slice may be configured by the method described in "16.3.4.2 AMF and NW Slice Selection" of 3GPP TS 38.300 V17.1.0 (2022-06).

[0065] First, the terminal 20 transmits a connection request including identification information of the network slice to which the terminal 20 wishes to connect to the CU 46 via the antenna 15, and in the base request process, the CU 46 acquires the connection request from the terminal 20 (S101). The identification information of the network slice may be, for example, the S-NSSAI included in the NSSAI from the terminal 20, or other information. Note that the processes shown in FIG. 4 performed by the CU 46 are processes included in the base request process. Note that if the connection request does not include identification information of the network slice, the network slice is not used.

[0066] Next, in the base station request process, the CU 46 checks whether the base station permits connection to the network slice indicated by the identification information acquired from the terminal 20 (S102). The CU 46 may determine that the connection is permitted if the identification information acquired from the terminal 20 is registered in a list of network slices supported by the base station. If the connection to the network slice indicated by the identification information acquired from the terminal 20 is not permitted (N in S102), the process of FIG. 4 ends, and the terminal 20 is not connected.

[0067] On the other hand, if connection to the network slice indicated by the identification information obtained from the terminal 20 is permitted (Y in S102), the CU46 determines whether the network slice to which the terminal 20 is requesting connection is a network slice of a closed network (S103).

[0068] If the network slice requesting connection is a network slice of a closed network (Y in S103), the CU 46 transmits a communication control request to the corresponding base control unit (AMF 47) included in the base system 43 (S104). The base control unit then performs processing such as authentication of the terminal 20, and the base control unit (SMF 48) then establishes a communication path (PDU session) between the terminal 20 and the UPF 49 included in the base system 43 (S105). The UPF 49 then relays communication between the terminal 20 and other systems, etc., via that communication path (S106).

[0069] On the other hand, if the network slice requesting connection is a different network slice from that of the closed network or if the connection request does not include identification information for the network slice (N in S103), the CU 46 sends a communication control request to the corresponding core control unit (AMF 47) included in the core network system 41 (S107). The core control unit then performs processing such as authentication of the terminal 20, and the core control unit (SMF 48) then establishes a communication path (PDU session) between the terminal 20 and the UPF 49 included in the core network system 41 (S108). The UPF 49 then relays communication between the terminal 20 and the external network via that communication path (S109).

[0070] 4 describes an explicit determination process, but instead, the CU 46 may acquire information indicating the AMF 47 stored in association with the network slice to which connection is requested, and send a control request to the acquired AMF 47. Here, the CU 46 included in the base system 43 may register the network slice of the closed network and the network slice for Internet access in a list, and further may store information on the AMF 47 of the base system 43 in association with the network slice of the closed network, and store the AMF 47 of the core network system 41 in association with the network slice for Internet access.

[0071] Here, when the terminal 20 starts communication via the antenna 17 included in the base station system 42, a process similar to but different from that shown in Figure 4 is executed. Below, the differences between the process when the terminal 20 starts communication via the antenna 17 and the process shown in Figure 4 will be described. Instead of the base request process by the CU 46 of the base system 43, the base station request process is executed by the CU 46 included in the base station system 42, and in S104, the CU 46 transmits a communication control request not to the base system 43 but to the corresponding base control unit (AMF 47) included in the base system 43. In addition, the process of S105 is executed by the core control unit in the core network system 41. Note that the AMF 47 that is the transmission destination in S104 and S107 may be the same or may be different for each network slice.

[0072] Next, actual communication routes between the CU 46 and the AMF 47 and between the terminal 20 and the UPF 49 will be described.

[0073] 5 is a diagram showing an example of a communication route when a terminal 20 accesses an external network such as the Internet via a base antenna 15. In the example of FIG. 5, the terminal 20 accesses a mobile communication network via the base antenna 15, and the terminal 20 requests connection to a network slice other than a network slice of a closed network. FIG. 5 shows a communication route when an access is made by a general terminal 20 that does not support a so-called closed network.

[0074] In this case, a request for communication control is sent from the CU 46 of the base system 43 to the AMF 47 in the core network system 41 (see the dashed arrow). After that, a communication path between the terminal 20 and the UPF 49 in the core network system 41 is established, and the UPF 49 relays communication between the terminal 20 and the external network (see the dashed arrow).

[0075] Fig. 6 is a diagram showing an example of a communication route when the terminal 20 accesses a closed network via the base antenna 15. In the example of Fig. 5, the terminal 20 accesses a mobile communication network via the base antenna 15, and the terminal 20 requests connection to the closed network. In this case, a request for communication control is sent from the CU 46 to the AMF 47 in the base system 43, and the UPF 49 in the base system 43 further relays communication between the terminal 20 and other systems (such as the voice communication system 61).

[0076] A case where the terminal 20 communicates via an antenna 17 arranged in a base station system 42 outside the base station will also be described. Fig. 7 is a diagram showing an example of a communication route when the terminal 20 accesses an external network via the antenna 17 outside the base station. In the example of Fig. 7, the terminal 20 accesses the mobile communication network via the antenna 17, and the terminal 20 requests connection to a network slice other than the network slice of the closed network.

[0077] In this case, a request for communication control is sent from the CU 46 of the base station system 42 to the AMF 47 in the core network system 41 (see the dashed arrow). After that, a communication path is established between the terminal 20 and the UPF 49 in the core network system 41, and the UPF 49 relays communication between the terminal 20 and the external network (see the dashed arrow). The example in Figure 7 differs from the example in Figure 5 mainly in that the antenna 15, DU 45, and CU 46 through which communication passes are located within the base station system 42.

[0078] 8 is a diagram showing an example of a communication route when the terminal 20 accesses a closed network via an antenna 17 outside a base station. In the example of FIG. 8, the terminal 20 accesses a mobile communication network via the antenna 17 of the base station system 42, and the terminal 20 requests connection to the closed network. In this case, a request for communication control is transmitted from the CU 46 to the AMF 47 in the core network system 41, while the UPF 49 in the base system 43 relays communication between the terminal 20 and other systems (such as the voice communication system 61). In this way, the core control unit (SMF 48) of the core network system 41 may control the UPF 49 included in the base system 43.

[0079] 6 and 8, the AMF 47 that controls communication may be different depending on whether the communication is via the antenna 15 in the base system 43 or via another antenna 17. In particular, as shown in this embodiment, when a voice communication system 61 or the like outside the mobile communication network provides calls via a telephone line network, the need for location information of the terminal 20 managed by the AMF 47 decreases, and this configuration can be adopted.

[0080] When the terminal 20 accesses the closed network via the antenna 17 outside the base station, a communication control request may be transmitted to a base station control unit (AMF 47) included in the base station system 43. In this case, the CU 46 of the base station system 42 executes the same process as the CU 46 of the base station system 43 when it receives a connection request from the terminal 20.

[0081] In this embodiment, a secure connection is ensured by allowing the terminal 20 to access other systems using a closed network. Furthermore, when the terminal 20 connects to a network slice of the closed network via the antenna 15 included in the base system 43, the terminal 20 can improve its resistance to trouble by transmitting a control request to the AMF 47 in the base system 43 instead of the core network system 41. In other words, for example, in a hospital, it is possible to provide access to an external network to visitors such as patients and provide access to the closed network to staff such as nurses and doctors, thereby making effective use of facilities such as the antenna 15 while maintaining security.

[0082] The present disclosure is not limited to the above-described embodiments. The configurations disclosed in the embodiments can be combined in various ways. Furthermore, part of the configuration described in the present embodiment may be modified within the scope of the technical idea of ​​the present disclosure.

[0083] Furthermore, the functional units according to the present embodiment may be realized using hypervisor-type or host-type virtualization technology instead of container-type virtualization technology. Furthermore, the functional units according to the present embodiment do not need to be implemented by software, but may be implemented by hardware such as electronic circuits. Furthermore, the functional units according to the present embodiment may be implemented by a combination of electronic circuits and software.

[0084] As can be understood from the description of the embodiments described above, this specification discloses various technical ideas, including the following disclosures.

[0085] (1) A base system is provided at a base and includes an antenna and one or more processors, and a core network system is connected to the base system and includes one or more processors, and at least one of the one or more processors provided in the base system executes a base request process, a base control process for controlling communication by the terminal, and a base relay process for communicating with the terminal based on the control and relaying data acquired from the terminal to another system provided at the base, and at least one of the one or more processors provided in the core network system executes a core control process for controlling communication by the terminal, and in the base request process, A communication system in which, in response to a request for connection to a network slice of a specified closed network transmitted from a terminal via the base antenna, the base system is requested to perform the base control processing for communication by the terminal, and in response to a request for connection to a network slice different from the network slice of the specified closed network transmitted from the terminal via the base antenna, the core network system is requested to perform the core control processing for communication by the terminal in a network slice different from the network slice of the specified closed network, and in response to the request for the base control processing by the base request processing, the base relay processing for communication by the terminal via the base antenna is initiated.

[0086] (2) In (1), the communication system further includes an external system having an external antenna and one or more processors and installed outside the base, wherein at least one of the one or more processors provided in the external system executes an external request process to request the core network system to perform the core control process for the communication of the terminal in the network slice of the specified closed network in response to a request for connection to the network slice of the specified closed network transmitted from the terminal via the external antenna.

[0087] (3) In (2), the communication system, in which the base relay process for communication by the terminal is started in response to a request for the core control process by the external request process.

[0088] (4) In any one of (1) to (3), the other system includes at least one of a SIP server, a nurse call system, and a database system.

[0089] (5) A communication control method comprising: controlling communication by a terminal by at least one of one or more processors included in a base system located at a base; communicating with the terminal based on the control; relaying data obtained from the terminal to another system located at the base; controlling communication by the terminal by at least one of one or more processors included in a core network system; causing at least one of the one or more processors included in the base system to control communication by the terminal in response to a request for connection from the terminal to a network slice of a specified closed network transmitted from the terminal via a base antenna included in the base system; causing at least one of the one or more processors included in the base system to control communication by the terminal in a network slice different from the network slice of the specified closed network in response to a request for connection from the terminal transmitted via the base antenna from the terminal; and when control of communication by at least one of the one or more processors included in the base system is started, starting relaying between the terminal and the other system via the base antenna.

Claims

1. A base system is provided at a base and includes a base antenna, and a core network system is connected to the base system, The base system: Base request processing; A site control process for controlling communication by the terminal; a base relay process is executed to communicate with the terminal based on the control and relay data acquired from the terminal to another system located at the base; The core network system A core control process for controlling communication by the terminal is executed; In the base request processing, in response to a request for connection to a network slice of a specified closed network transmitted from the terminal via the base antenna, the base system is requested to perform the base control processing for communication by the terminal, and in response to a request for connection to a network slice different from the network slice of the specified closed network transmitted from the terminal via the base antenna, the core network system is requested to perform the core control processing for communication by the terminal in a network slice different from the network slice of the specified closed network; In response to a request for the base control process by the base request process, the base relay process for communication by the terminal via the base antenna is started. Communication systems.

2. An external system including an external antenna and installed outside the base; The external system: In response to a request for connection to a network slice of the specified closed network transmitted from the terminal via the external antenna, an external request process is executed to request the core network system to perform the core control process for the communication of the terminal in the network slice of the specified closed network. The communication system according to claim 1 .

3. In response to a request for the core control process by the external request process, the site relay process for communication by the terminal is started. The communication system according to claim 2 .

4. The other system includes at least one of a SIP server, a nurse call system, and a database system. The communication system according to claim 1 .

5. Depending on the base system installed at the base, Controlling communication by terminals; communicating with the terminal based on the control and relaying data acquired from the terminal to another system located at the base; Controlling communication by the terminal through a core network system; The base system: in response to a request for connection to a network slice of a specified closed network transmitted from the terminal via a base antenna included in the base system, having the base system control communication by the terminal, and in response to a request for connection to a network slice different from the network slice of the specified closed network transmitted from the terminal via the base antenna, having the core network system control communication of the terminal in a network slice different from the network slice of the specified closed network; When the base system starts to control communication, the base system starts relaying communication between the terminal and the other system via the base antenna. Communications control method.