Communication control device, communication control method, and cellular network

Abstract

To improve communication quality of traffic between a mobile terminal and an edge server.SOLUTION: A control part of a communication control device performs a control so that a switch condition of a first traffic based on deterioration of a communication quality in accordance with the current or a feature first traffic is satisfied in a state where communication with a first edge server in accordance with the first traffic and a second traffic is performed via a cellular network by a mobile terminal, and a communication mating in accordance with the first traffic of the mobile terminal is switched from the first edge server to the second edge server in the cellular network in the case where the second edge server that can be replaced from the first edge server is discovered.SELECTED DRAWING: Figure 7

Description

[Technical field]

[0001] The present disclosure relates to a communication control device, a communication control method, and a cellular network. [Background technology]

[0002] Conventionally, there is the following technology. Middleware in a cloud system has a monitoring function, a switching function, and a redistribution function. The monitoring function monitors the network status and the respective operating statuses of the cloud server, edge server, and user devices. The switching function dynamically switches the system configuration, including the network topology, based on the monitoring results. The redistribution function redistributes the operation destination of services in conjunction with the switching of the system configuration (for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2019-135578 A Summary of the Invention [Problem to be solved by the invention]

[0004] An object of the present disclosure is to provide a communication control device, a communication control method, and a cellular network that enable a mobile terminal to perform suitable communication with an edge server for specified traffic passing through a cellular network. [Means for solving the problem]

[0005] According to an aspect of the present disclosure, a mobile terminal transmits, via a cellular network, a communication related to a first traffic and a second traffic having a tolerable delay longer than the tolerable delay of the first traffic, to a first edge. The communication quality of the first traffic in the current or future state when the first traffic is being The communication control device includes a control unit that controls switching of a communication partner for the first traffic of a mobile terminal in a cellular network from the first edge server to the second edge server when a switching condition for the first traffic based on a decrease in the first traffic is satisfied and a second edge server that can substitute for the communication for the first traffic is found.

[0006] According to an aspect of the present disclosure, a mobile terminal transmits, via a cellular network, a communication related to a first traffic and a second traffic having a tolerable delay longer than the tolerable delay of the first traffic, to a first edge. The communication quality of the first traffic in the current or future state when the first traffic is being The communication control method includes a communication control device controlling, in a cellular network, switching of a communication partner for a first traffic of a mobile terminal from a first edge server to a second edge server when a switching condition for a first traffic based on a decrease in a first edge server is satisfied and a second edge server that can substitute for communication related to the first traffic is found.

[0007] Another aspect of the present disclosure is a cellular network connected to a mobile terminal, in which the mobile terminal is performing communication with a first edge server via the cellular network regarding a first traffic and a second traffic having a tolerable delay longer than the tolerable delay of the first traffic, of the first traffic based on a current or future deterioration in communication quality of the first traffic. When the switching condition is satisfied and a second edge server capable of handling the communication related to the first traffic is found, the communication partner of the mobile terminal related to the first traffic is switched from the first edge server to the second edge server.

[0008] The present disclosure further provides a communication system including the above-mentioned communication control device, a computer, It may include a program for operating as a communication control device, or a computer-readable storage medium on which the program is recorded. Effect of the Invention

[0009] According to the present disclosure, it is possible for a mobile terminal to perform suitable communication with an edge server for specific traffic passing through a cellular network. [Brief description of the drawings]

[0010] [Figure 1] FIG. 1 is a diagram illustrating an example of the configuration of a communication system according to an embodiment. [Diagram 2] FIG. 2 is a diagram showing details of network nodes (components) that make up a cellular network. [Diagram 3] FIG. 3 is a table showing the first traffic switching conditions. [Figure 4] 4A and 4B are diagrams showing configuration examples of an information processing device (computer) capable of operating as a communication control device and a network node. [Diagram 5] 5A and 5B are diagrams for explaining a first operation example (first edge server switching method) in a communication system. [Figure 6] FIG. 6 is a sequence diagram showing a first operation example (a method for switching between edge servers) in the communication system. [Figure 7] FIG. 7 is a diagram for explaining a second operation example (edge ​​server switching method) in the communication system. [Figure 8] FIG. 8 is a diagram illustrating a second operation example in the communication system. [Figure 9] FIG. 9 is a sequence diagram showing a third operation example in the communication system. [Figure 10] FIG. 10 is a diagram illustrating the third operation example. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] Hereinafter, embodiments of a communication control device, a communication control method, and a cellular network will be described with reference to the drawings. The configurations of the following embodiments are merely examples, and the present disclosure is not limited to the configurations of the embodiments. FIG. 1 is a diagram showing an example of a communication system according to an embodiment. The communication system includes a cellular network 4 consisting of a core network 3A and a RAN (Radio Access Network) 4, a mobile terminal (wireless terminal, hereinafter referred to as UE (User Equipment)) 10, a cloud server 1, and one or more edge servers (also called MEC (Mobile Edge Computing) servers, EAS (Edge Application Servers)) 2.

[0012] The cloud server 1 is connected to an external network such as the Internet 1A. The UE 10 can transmit data to the cloud server 1 and receive data from the cloud server 1 by connecting to the cloud server 1 via a cellular network 3.

[0013] The edge server 2 is a server having the same functions as the cloud server 1, and is placed closer to the UE 10 than the cloud server 1. When the length of delay (latency) associated with the distance between the UE 10 and the cloud server 1 is not suitable for providing a predetermined service, the UE 10 is connected to the edge server 2 instead of the cloud server 1. This allows the UE 10 to receive the same service as if it were connected to the cloud server 1.

[0014] The edge server 2 may be located outside the core network 3A (called a central site) or may be located within the cellular network 3 (called a local site). A plurality of edge servers 2 are provided so as to be able to handle changes in location (handover) associated with the movement of the UE 10.

[0015] In this embodiment, the cloud server 1 and the edge server 2 provide a user of the UE 10 with a service related to the metaverse (a three-dimensional virtual space constructed on the Internet). For example, the cloud server 1 provides image data of the metaverse space to the UE 10, and the user can operate an avatar (an alter ego of the user) in the metaverse space displayed on the screen to perform various events. The UE 10 may be carried by a pedestrian or may be mounted on a moving body such as a vehicle 6. The vehicle 6 may be a vehicle driven by a person or an autonomous vehicle.

[0016] 2 is a diagram showing details of network nodes (components) constituting the cellular network 3. The cellular network 3 may be, for example, a fourth generation mobile communication system (4G network (LTE network)), a fifth generation mobile communication system (5G network), or a sixth generation mobile communication system (6G network). In this embodiment, a case where the cellular network 3 is a 5G network will be described.

[0017] In FIG. 2, UE 10 is a terminal of a user (subscriber). RAN (Radio Access Network) 4 is an access network to a core network (called 5G Core (5GC)) 3A. RAN 4 is composed of a necessary number of base stations (called gNB) 5 to cover the communication area of ​​UE 10. Each base station 5 is wirelessly connected to one or more UEs 10. A DN (Data Network) 5 is connected to a user plane (UDP 11b) of the core network 3A.

[0018] 5GC is composed of a set of components (network nodes) with specific functions called NFs (Network Functions). In Fig. 1, the following are illustrated as NFs 11 that compose 5GC. In Fig. 2, they are shown as thick-lined rectangles. Each of NFs 11a to 11k is a function that is realized by one or more information processing devices (computers) executing a program. UPF(User Plane Function)11a AMF (Access and Mobility Management Function)11b SMF (Session Management Function)11c PCF(Policy Control Function)11d NEF(Network Exposure Function)11e NRF(Network Repository Function)11g NSSF(Network Slice Selection Function)11h AUSF(Authentication Server Function)11i UDM(Unified Data Management)11j NWDAF(Network Data Analytics Function)11k

[0019] The UPF 11a is the only network node for the user plane in 5GC. All nodes other than the UPF 11a are network nodes for the control plane. The UPF 11a routes and forwards user packets (user plane packets transmitted and received by the UE 10), inspects packets, and processes QoS. The AMF 11b is a device in the core network 3A that accommodates the UE 10. The AMF 11b accommodates the RAN 4 (base station 5), and performs subscriber authentication control and location (mobility) management of the UE 10. The UDM 11j provides subscriber information, or acquires, registers, deletes, and changes the status of the UE 10.

[0020] The SMF 11c manages a PDU (Protocol Data Unit) session and controls the UPF 11a to implement QoS (Quality of Service) control and policy control. The PDU session is a virtual communication path for data exchange between the UE 10 and the DN 8. The DN 8 is a data network (such as the Internet) outside the 5GC (called a central site). The cloud server 1 is connected to the DN 8.

[0021] The PCF 11d performs QoS control, policy control, billing control, etc. under the control of the SMF 11c. QoS control controls the quality of communication, such as priority transfer of packets. In the network control, communication control such as QoS based on network or subscriber information, packet forwarding availability, and billing is performed. The NEF11e plays a role of mediating communication between external nodes such as the AF12 and nodes in the control plane. The AF12 operates as an application server (external server) outside the 5GC. However, the AF12 may be arranged as an external device of the core network 3A or as a component of the core network 3A.

[0022] The NRF 11g stores and manages information on NFs (e.g., AMF, SMF, UPF, etc.) in the 5GC. In response to an inquiry about an NF to be used, the NRF 11g can return multiple NF candidates to the inquiry source.

[0023] The NSSF11h has a function of selecting a network slice to be used by a subscriber from among the network slices generated by network slicing. A network slice is a virtual network with specifications according to the application.

[0024] The AUSF 11i is a subscriber authentication server that performs subscriber authentication under the control of the AMF 11b. The UDM 11j holds subscriber-related information. The NWDAF 11k has the function of collecting and analyzing data from each NF 11, OAM (Operations, Administration, and Maintenance) terminal, and external devices of the 5GC. The NWDAF 12 is an NF that provides network analysis information. The OAM terminal 8 has the function of operating, managing, and maintaining the core network 3A (5GC).

[0025] When the UE 10 establishes a wireless connection with the base station 5, it transmits predetermined information to the AMF 11b via the base station 5. The AMF 11 registers location information of the UE 10 in the UDM 11j. When the AUSF 11i successfully authenticates the UE 10, the AMF 11 instructs the SMF 11c to establish a PDU session for the UE 10 to communicate with the cloud server 1 or the edge server 2. The SMF 11c selects the UPF 11a corresponding to the cloud server 1 or the edge server 2, and instructs the selected UPF 11a to establish a PDU session. The UPF 11a establishes a PDU session between the UE 10 and the cloud server 1 or the edge server 2.

[0026] The edge server 2 is connected to the UPF 11a. As described above, the edge server 2 can be placed either outside (central site) or inside (local site) of the core network 3A, or both. The UPF 11a placed at the boundary with the DN8 is called a PSA (PDU Session Anchor)-UPF (anchor UPF). In contrast, a UPF placed at a local site and continuous with the PSA-UPF at the central site is called an Intermediate UPF. Also, a PSA-UPF for the DN of the local site can be placed at the local site. The MBH 7 is a network formed by multiple relay stations (routers, etc.) that forward IP packets transmitted from the base station 5.

[0027] In this embodiment, between the UE 10 and the edge server 2, a plurality of PDU sessions are established according to the types of data transmitted and received between the UE 10 and the edge server 2.

[0028] In this embodiment, as an example, data is divided into the following three types (1) to (3) and transmitted using different traffic (PDU sessions). That is, a different PDU session is established for each type of data. The number of types of data may be other than three. (1) Data having real-time characteristics and used to provide services related to the metaverse (referred to as metaverse real-time data or first data). (2) Data sent on a best effort basis (referred to as second data). (3) Target data collected by the edge server 2 or the cloud server 1 (referred to as third data).

[0029] Of the three types of data, the third data has the longest permissible delay (latency) in transmission, the second data has the next longest permissible delay, and the first data has the shortest permissible delay.

[0030] Then, a PDU session for the first traffic (referred to as the first session) that is the traffic of the first data is established between the UE 10 and the UPF 11a. Also, a PDU session for the second traffic (referred to as the second session) that is the traffic of the second data is established. Also, a PDU session for the third traffic (referred to as the third session) that is the traffic of the third data is established.

[0031] A communication control device 15 that controls switching of the edge server 2 is provided in the core network 3A (5GC). In this embodiment, an example is shown in which the communication control device 15 is provided as a new NF of the 5GC. However, the function of the communication control device 15 may be implemented in an existing NF such as the NWDAF 11k. In addition, the communication control device 15 may be an external device (AF 12) of the 5GC connected to the 5GC via the NEF 11e.

[0032] The communication control device 15 collects information indicating the status of the network between the UE 10 and the edge server 2 and around the edge server 2, or information indicating the load of the edge server 2, and monitors the network status and the load of the edge server 2.

[0033] If it is determined as a result of the monitoring that a predetermined switching condition is satisfied, the communication control device determines whether an edge server 2 (referred to as a second edge server) capable of substituting for the current edge server 2 (referred to as a first edge server) has been found. If it is determined that a second edge server has been found, it outputs information (a control signal) for switching communication related to the traffic of the first data from the first edge server to the second edge server. The core network 3A (5GC) switches the edge server 2 according to the determination.

[0034] The switching condition is a condition indicating a deterioration in communication quality of the first traffic (traffic related to the metaverse) in the present or future. For example, as a condition indicating a deterioration in the present communication quality (QoS: Quality of Service), at least one of the following may be selected, as shown in FIG. 3: exceeding a threshold for network delay, exceeding a threshold for load on an edge server, exceeding an allowable range for jitter, decreasing below a threshold for throughput, and exceeding a threshold for packet error rate. In addition, as a condition indicating a deterioration in communication quality in the future, the demand forecast exceeding a threshold, or the movement speed of the UE 10 (such as a moving average of the movement speed) exceeding a threshold may be exemplified. The demand forecast exceeding a threshold may indicate an increase in the load on the edge server 2 in the future. In addition, the movement speed of the UE 10 exceeding a threshold means that the RTT (round trip time) is prolonged (the allowable delay will not be satisfied in the future). Regarding the threshold used to determine whether the switching condition is satisfied, two or more levels (classes) may be provided for the demand forecast and the movement speed, and different thresholds may be provided for each level.

[0035] As the second edge server capable of substituting for the first edge server, an edge server 2 is selected that is expected to improve (improve communication quality) by switching in terms of the communication quality index (e.g., network delay) used to determine whether the switching condition is satisfied. For example, if there is an edge server 2 that is closer to the location of the UE 10 than the first edge server, that edge server 2 is set as the second edge server.

[0036] The search for the second edge server is performed, for example, by using a DNS (Domain Name System) system. The UE 10 transmits a DNS query for the IP address of the edge server 2, etc. The DNS query is received, for example, by a DNS server (or a DNS resolver), and the DNS server returns a response including the IP address of the edge server 2, etc., in response to the DNS query, to the UE 10. When the IP address or the like of the edge server 2 is indicated in the response to the DNS query, it indicates that the desired edge server 2 has been found.

[0037] Fig. 4A is a diagram showing a configuration example of an information processing device (computer) capable of operating as the NFs 11a to 11k, the AF 12, or the communication control device 15. Fig. 4B is a diagram showing a configuration example of an information processing device capable of operating as the UE 10.

[0038] In FIG. 2A, the information processing device 20 includes, for example, a processor 31, a storage device 32, a communication interface (communication IF) 33A, an input device , and a display 35, which are interconnected via a bus .

[0039] The storage device 32 stores various programs and data. The processor 31 is an example of a control unit (controller), and is a CPU, a DSP, a GPU, or a combination of these. The processor 31 executes the programs stored in the storage device 32 and performs various processes, such as calculations or processing using the data stored in the storage device 32. By executing the programs, the information processing device 20 can perform the operations of the NF 11, the AF 12, and the communication control device 15. The communication IF 33A is a communication interface circuit for a wired network. The input device 34 is a button, a key, a touch panel, etc. used for inputting and setting information. The display 35 is used for displaying information. In addition to the configuration of the information processing device 20, the information processing device 20A includes a wireless communication IF 33B. The wireless communication IF 33B is used for wireless communication with the base station 5. By executing the programs by the processor 31 of the information processing device 20A, various operations as the UE 10 can be performed.

[0040] 5A and 5B are diagrams for explaining a first operation example (first edge server switching method) in a communication system. In FIG. 5A, a UE 10a is connected to a UPF 11a1 via a RAN 4 in the user plane. The UPF 11a1 is a PSA-UPF of a central site, and is connected to a DN8 of the central site. An edge server 2a is connected to the DN8.

[0041] The UE 10a communicates with the edge server 2a to receive services related to the metaverse. For this reason, PDU sessions (first to third sessions) related to the first, second, and third traffic are established between the UE 10a and the edge server 2a.

[0042] FIG. 6 is a sequence diagram showing a first operation example in the communication system. The UPF 11a1 collects information (such as network delay, jitter, throughput, and packet error rate) related to the communication related to the first traffic between the UE 10a and the edge server 2a. In addition, the UPF 11a1 can obtain information indicating the load of the edge server 2a from, for example, the edge server 2a or from a server other than the edge server 2a. The UPF 11a1 sends the obtained information to the 5GC CP-NF (FIG. 6). <1> ) 5GC CP-NF is the NF (SMF, AMF, etc.) of the 5GC control plane.

[0043] The information from the UPF 11a1 is received by, for example, the SMF 11c in the 5GC CP-NF, and is sent to the communication control device 15 as monitoring information (see FIG. 6). <2> ). The communication control device 15 can also obtain location information of the UE 10 registered in the UDM 11j, for example, and calculate the moving speed of the UE 10a from changes in the location of the UE 10a over time. The communication control device 15 can also receive information indicating a demand forecast input from, for example, the input device 34. The method of collecting monitoring information by the communication control device 15 is not limited to the above example.

[0044] The operation of the communication control device 15 is performed by the program of the information processing device 20 that operates as the communication control device 15. The process is carried out by the processor 31 executing a program stored in the storage device 32. The communication control device 15 performs monitoring (analysis of monitoring information) using monitoring information and can perform switching determination processing (see FIG. 6). <3> ).

[0045] In the switching determination process, the communication control device 15 can determine, through analysis of monitoring information, whether one or more (a predetermined combination) of multiple switching conditions are satisfied with respect to the communication of the first traffic between the UE 10a and the edge server 2a.

[0046] If it is determined that the switching condition is satisfied, the processor 31 of the communication control device 15 The system searches for a second edge server that can replace the edge server 2a (FIG. 6). <4> For example, the communication control device 15 generates and transmits a DNS query for an IP address or the like of an edge server 2 (e.g., an edge server 2 at a local site) closer to the UE 10 than the edge server 2a. The DNS query is received by, for example, a DNS server, and if the corresponding edge server 2 exists, the DNS server returns a response to the DNS query including the IP address or the like of the edge server 2. Note that a configuration may be adopted in which the communication control device 15 commands the UE 10 or the NF in the 5GC to search for a second edge server (send a DNS query) and receives the result (contents of the response).

[0047] When the communication control device 15 receives a response including the IP address of the edge server 2 (when the response includes the IP address of the edge server 2), the communication control device 15 determines that the second edge server has been found (see FIG. 6). <5> On the other hand, if the response does not include an IP address or the like, or if the response does not return within a predetermined time, the communication control device 15 can determine that the second edge server has not been found.

[0048] When it is determined that the second edge server is found, the communication control device 15 performs control to switch the communication related to the first traffic from the first edge server to the second edge server. That is, the communication control device 15 outputs information (PDU session establishment instruction) for establishing a new PDU session for the communication of the first traffic with the second edge server (FIG. 6 <6> The instruction is sent to, for example, the NF of the 5GC or the UE 10.

[0049] For example, assume that an edge server 2b located at a local site is found as a second edge server as shown in Fig. 5B. The edge server 2b is connected to a UPF 11a2 that operates as a PSA-UPF of the local site.

[0050] In response to the instruction to establish a PDU session, a procedure for establishing a PDU session between the UE 10 and the edge server 2b is executed (see FIG. 6). <7> ). For example, the SMF 11c selects the UPF 11a2 and instructs the UPF 11a2 to establish a PDU session between the UE 10a and the edge server 2b. As a result, a new PDU session for the first traffic is established between the UE 10a and the edge server 2b. A message (response) indicating completion of the establishment of the PDU session is sent from the 5GC CP-NF to the communication control device 15 (see FIG. 6). <8> ).

[0051] The communication control device 15 sends information (release instruction) for releasing the old session (the PDU session between the UE 10a and the edge server 2a) to the 5GC CP-NF or the UE 10 (FIG. 6 <9> ). This causes the release procedure of the PDU session between the UE 10a and the edge server 2a to be executed (FIG. 11).

[0052] When the release procedure is executed, a message indicating the completion of the release is sent to the communication control device 15 (see FIG. 6). <11> ). In this way, the so-called make-before-break ) method is used to switch the edge server 2. As a result, the first traffic is sent to both the edge server 2a and the edge server 2b until the old session is released. Switching from the edge server 2a to the edge server 2b is performed seamlessly.

[0053] FIG. 7 is a sequence diagram showing a second operation example in the communication system. <1> , <2> and <3> Since this is the same as the first operation example, the explanation will be omitted.

[0054] If it is determined that the switching condition is satisfied, the communication control device 15 generates a DNS query for searching for a second edge server and transmits it to the 5GC (FIG. 7). <4> ).

[0055] FIG. 8 is an explanatory diagram of a second operation example. As shown in FIG. 8, an Edge Application Server Discovery Function (EASDF) 16 is provided in the 5GC as an NF that supports edge computing. The EASDF 16 receives a DNS query and transfers it to a DNS server. Next, the EASDF 16 receives a DNS response, and if the DNS response includes an IP address or the like of the edge server 2, it is determined that a second edge server has been discovered (see FIG. 7). <6> For example, assume that the IP address of the edge server 2b is included.

[0056] In this case, the EASDF 16 notifies the SMF 11c of the information (such as the IP address) included in the DNS response. The SMF 11c inserts the UPF 11a2, which is a PSA-UPF of the local site, between the RAN 4 and the UPF 11a1 based on the information such as the IP address of the edge server 2. The SMF 11c also sets the ULCL (uplink classifier) ​​for the UPF 11a2 (see FIG. 7). <7> ) By setting the ULCL, the first traffic packet destined for the edge server 2 received by the UPF 11a2 is transferred to the edge server 2b. The ULCL (uplink classifier) ​​is set so that there is traffic (second and third) other than that destined for the edge server 2. After that, a completion report may be transmitted from the 5GC to the communication control device 15.

[0057] 7, a configuration may be adopted in which the DNS response is transmitted to the communication control device 15, and the communication control device 15 determines whether or not the second edge server is found. In this case, when it is determined that the second edge server is found, a ULCL setting instruction including the contents of the DNS response can be transmitted from the communication control device 15 to the SMF 11c.

[0058] In the second operation example, the edge server 2 can be switched on the network side without information being passed to the UE 10. Instead of the ULCL, a branch point (BP) may be set in the UPF 11a2. In this case, the UE 10a is notified of prefix information for multihoming, and the prefix information is added to the first traffic data. The UPF 11a2, which is the branch point, can transfer the first traffic data destined for the edge server 2 to the edge server 2b according to the prefix information.

[0059] Fig. 9 is a sequence diagram showing a third operation example in the communication system. Fig. 10 is a diagram for explaining the third operation example. As shown in Fig. 10, in the third operation example, it is assumed that the UE 10a has established a PDU session related to the first to third traffic with the edge server 2b via the UPF 11a2. In Fig. 9, <1> , <2> , <3> and <4> is the same as the first operation example (FIG. 6), so the explanation will be omitted.

[0060] However, in the third operation example, the first traffic is switched to the DNS query response. Edge server 2 is not found (or the DNS query response does not arrive within the specified period) This case is expected (Figure 9 <5> ).

[0061] In this case, the communication control device 15 transmits a switching instruction for the second session, which is a PDU session related to the second traffic, to the UE 10 (see FIG. 9). <6> The switching instruction may be sent to the UE 10 via a route that does not pass through the cellular network 3, or may be sent via a route that passes through the cellular network 3.

[0062] When the switching instruction is received by the UE 10a, the second session is released by the UE 10a and the NFs of the cellular network 3 including the UPF 11a2 (see FIG. 9). <7> Following the release of the second session, a procedure for establishing a new second session (a PDU session for communication related to the second traffic) with the edge server 2a at the central site or the cloud server 1 (both of which are known from the perspective of the UE 10a) is performed (see FIG. 9). <8> Here, as an example, a PDU session between the UE 10a and the edge server 2a is established. The second session is switched in a so-called break-before-make manner. can be done.

[0063] In the third operation example, if the edge server 2 to which the first traffic is to be switched is not found, the second traffic is switched to an edge server 2a (which may be the cloud server 1) other than the edge server 2b. This reduces the load on the edge server 2b, and is expected to improve or enhance the quality of communication related to the first traffic.

[0064] Figure 9 <9> ~ <12> The operation of is performed when it is determined that the switching condition is satisfied. This can be combined with not only the third operation example but also the first and second operation examples. <9> In the step S200, it is determined whether or not there is a third session between the UE 10a and the edge server 2b, which is a PDU session related to the third traffic. If there is no third session, the process shown in FIG. <10> No further action is taken.

[0065] When it is determined that the third session exists, the communication control device 15 sends a release instruction for the third session to the UE 10 (see FIG. 9). <10> The release command may be sent via a route that passes through the cellular network 3, or may be sent via a route that does not pass through the cellular network 3.

[0066] When the UE 10a receives the release instruction, the third session is released by the UE 10a and the NFs of the cellular network 3 including the UPF 11a2. As a result, transmission and reception of data related to the third traffic in the third session is prohibited (stopped). This reduces the load on the edge server 2b.

[0067] According to the embodiment, the UE 10 (an example of a mobile terminal) communicates with the edge server 2a regarding the first traffic and the second traffic via the cellular network 3. In this state, the first traffic based on the current or future deterioration of the communication quality of the first traffic is detected. When the switching condition of the first traffic is satisfied, a second edge server capable of substituting for the communication related to the first traffic is searched for. When the second edge server is found, the processor 31 (an example of a control unit) of the communication control device 15 controls switching of the communication partner of the first traffic of the UE 10 from the edge server 2a (an example of a first edge server) to the edge server 2b (a second edge server) in the cellular network 3. This enables the UE 10 to communicate favorably with the edge server 2 for the predetermined traffic passing through the cellular network 3.

[0068] According to the embodiment, the processor 31 (control unit) of the communication control device 15 can perform the following when the switching condition is satisfied but the second edge server does not exist (is not found). That is, the processor 31 performs the following when the second traffic of the UE 10 is detected as shown in FIG. It is possible to control switching of the communication partner of a traffic from edge server 2b (FIG. 10: an example of the first edge server) to edge server 2a (FIG. 10: an example of an edge server other than the second edge server) or cloud server 1. This can reduce the load on edge server 2.

[0069] Furthermore, according to the embodiment, the communication control device 15 (processor 31) allows the UE 10 and the edge server 2 to perform communications related to the first traffic, the second traffic, and the third traffic via the cellular network 3. In this case, when a switching condition is satisfied, the communication control device 15 (processor 31) can perform control to stop the communication related to the third traffic. This can reduce the load on the edge server 2.

[0070] The first traffic switching condition is exceeding a threshold of network delay, At least one of exceeding a load threshold, exceeding a jitter tolerance range, exceeding a throughput threshold, exceeding a packet error rate threshold, exceeding a demand forecast threshold, and exceeding a moving speed threshold of the UE 10 can be selected.

[0071] The first traffic may be traffic of real-time data related to the metaverse. The second traffic may be traffic that transmits data on a best-effort basis. The communication control device 15 may be a device that constitutes the cellular network 3, or may be a device outside the cellular network 3 that is connected to the cellular network 3. The communication control device 15 (processor 31) may control the switching of the first traffic by a make-before-break method. The communication control device 15 (processor 31) may control the switching of the second traffic by a break-before-make method.

[0072] The above-described embodiment and modified examples are merely examples, and the present disclosure may be modified as appropriate without departing from the spirit and scope of the present disclosure. Furthermore, the processes and means described in the present disclosure may be freely combined and implemented as long as no technical contradiction occurs.

[0073] Furthermore, a process described as being performed by one device may be shared and executed by multiple devices. Or, a process described as being performed by different devices may be executed by one device. In a computer system, the hardware configuration (server configuration) by which each function is realized can be flexibly changed.

[0074] The present disclosure can also be realized by supplying a computer program implementing the functions described in the above embodiments to a computer, and having one or more processors of the computer read and execute the program. Such a computer program may be provided to the computer by a non-transitory computer-readable storage medium connectable to the system bus of the computer, or may be provided to the computer via a network. The non-transitory computer-readable storage medium includes any type of medium suitable for storing electronic instructions, such as, for example, a magnetic disk (e.g., a floppy disk, a hard disk drive (HDD), etc.), an optical disk (e.g., a CD-ROM, a DVD disk, a Blu-ray disk, etc.), a read-only memory (ROM), a random access memory (RAM), an EPROM, an EEPROM, a magnetic card, a flash memory, or an optical card. [Explanation of symbols]

[0075] 1···Cloud server, 2···Edge server, 3···Cellular network, 3A···Core network, 4···RAN, 5···Base station, 10···UE, 15···Communication control device, 20···Information processing device, 31···Processor, 32···Storage device

Claims

1. A mobile terminal communicates with a first edge server via a cellular network, the first traffic and the second traffic having a permissible delay longer than the permissible delay of the first traffic. In a state where the first traffic is being transmitted, a first traffic quality degradation is detected based on the current or future degradation of the communication quality of the first traffic. a control unit that controls switching of a communication partner of the first traffic of the mobile terminal from the first edge server to the second edge server in the cellular network when the switching condition of the first traffic is satisfied and a second edge server capable of substituting for the communication related to the first traffic is found. A communication control device including:

2. 2. The communication control device according to claim 1, wherein the control unit performs control to switch the communication partner of the second traffic of the mobile terminal from the first edge server to an edge server other than the second edge server or a cloud server when the switching condition is satisfied but the second edge server is not found.

3. The control unit performs control to stop communication related to the third traffic when the switching condition is satisfied in a case where the mobile terminal and the first edge server are performing communication related to the first traffic, the second traffic, and a third traffic having a longer allowable delay than the second traffic via the cellular network. The communication control device according to claim 1 or 2.

4. The first traffic switching condition is exceeding a threshold of network delay, a first edge server At least one of exceeding a threshold of the load of the server, exceeding a tolerable range of jitter, exceeding a threshold of the throughput, exceeding a threshold of the packet error rate, exceeding a threshold of the demand forecast amount, and exceeding a threshold of the moving speed of the mobile terminal is selected. The communication control device according to claim 1 .

5. The first traffic is a traffic of real-time data related to the metaverse. The communication control device according to claim 1 .

6. The communication control device according to claim 1 or 5, wherein the second traffic is traffic in which data is transmitted on a best effort basis.

7. The communication control device configures the cellular network. The communication control device according to claim 1 .

8. The communication control device is connected to the cellular network. The communication control device according to claim 1 .

9. The control unit controls switching of the first traffic by a make-before-break method. The communication control device according to claim 1 .

10. The control unit controls switching of the second traffic by a break-before-make method. The communication control device according to claim 2.

11. A communication control device A mobile terminal communicates with a first edge server via a cellular network, the first traffic and the second traffic having a permissible delay longer than the permissible delay of the first traffic. In a state where the first traffic is being transmitted, a first traffic quality degradation is detected based on the current or future degradation of the communication quality of the first traffic. When the switching condition for the first traffic is satisfied and a second edge server capable of substituting for the communication related to the first traffic is found, the cellular network controls switching of a communication partner related to the first traffic of the mobile terminal from the first edge server to the second edge server. A communication control method comprising the steps of:

12. When the switching condition is satisfied but the second edge server is not found, the communication control device controls switching of a communication partner related to the second traffic of the mobile terminal from the first edge server to an edge server other than the second edge server or a cloud server. The communication control method according to claim 11, further comprising:

13. When the mobile terminal and the first edge server are performing communications related to the first traffic, the second traffic, and a third traffic having a longer allowable delay than the second traffic via the cellular network, the communication control device controls the stop of the communication related to the third traffic when the switching condition is satisfied. The communication control method according to claim 11 or 12, further comprising:

14. The switching condition is at least one selected from among exceeding a network delay threshold, exceeding a load threshold of the first edge server, exceeding an allowable range of jitter, exceeding a throughput threshold, exceeding a packet error rate threshold, exceeding a demand forecast threshold, and exceeding a moving speed threshold of a mobile terminal. The communication control method according to claim 11.

15. The first traffic is a traffic of real-time data related to the metaverse. The communication control method according to claim 11.

16. 16. The communication control method according to claim 11, wherein the second traffic is traffic in which data is transmitted on a best effort basis.

17. The communication control device controls switching of the first traffic by a make-before-break method. The communication control method according to claim 11.

18. The communication control device determines to switch the second traffic by a break-before-make method. The communication control method according to claim 12.

19. A cellular network connected to a mobile terminal, The mobile terminal transmits, via a cellular network, communications related to a first traffic and a second traffic having a tolerable delay longer than the tolerable delay of the first traffic to a first edge server. In the state where the above is being performed, the present or future deterioration of communication quality related to the first traffic is and when a switching condition for the first traffic based on the first edge server is satisfied and a second edge server capable of substituting for the communication related to the first traffic is found, the communication partner of the mobile terminal related to the first traffic is switched from the first edge server to the second edge server. A cellular network characterized by:

20. When the switching condition is satisfied but the second edge server is not found, it is determined to switch a communication partner related to the second traffic of the mobile terminal from the first edge server to an edge server other than the second edge server or a cloud server.

20. The cellular network of claim 19.

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