System and method

Abstract

To provide a system and a method, capable of suppressing resource consumption as a whole system in international roaming.SOLUTION: A system 10 comprises: a SGW 300; a plurality of PGWs 100 and 200; and storage parts 32 and 34. Each of the PGWs is arranged to a HPLMN of which an ASN is different, the same IP address is allocated to each of the PGWs. The SGW is transmitted to the PGW of which a session generation request of a communication terminal 60 is selected. Each PGW generates session information of the communication terminal, registers the session information to the storage part, and transmits a session generation responce to the SGW. The SGW transmits up-link data of the communication terminal to each PGW after the reception of the session generation responce. Each PGW acquires the session information from the storage part if the PGW does not hold the session information.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a system and method. [Background technology]

[0002] Patent Document 1 describes a communication system that reduces packet transmission delays in international roaming. Patent Document 2 describes a communication system that reduces communication delays in roaming communications. [Prior art document] [Patent documents] [Patent Document 1] International Publication No. 2014 / 049668 [Patent Document 2] International Publication No. 2020 / 261458 Summary of the Invention [Means for solving the problem]

[0003] According to an embodiment of the present invention, there is provided a system. The system may include a Serving Gateway (SGW). The system may include a plurality of Packet Data Network Gateways (PGWs). The system may include a storage unit. Each of the plurality of PGWs may be located in a network having a different Autonomous System number (ASN), and each of the PGWs may be assigned the same Internet Protocol (IP) address. The SGW may include a request transmission unit that transmits a session creation request of a communication terminal requesting the creation of a session to a Packet Data Network (PDN), to a PGW selected from the plurality of PGWs as a destination of the session creation request based on predetermined PGW selection conditions. The PGW selected as the transmission target of the session generation request may include a request receiving unit that receives the session generation request, a session information generating unit that generates session information of the communication terminal including an IP address of the communication terminal, the IP address of the PGW, a TEID (Tunnel Endpoint IDentifier) ​​assigned to a communication tunnel of each of the PGWs, an IP address of the SGW, and a TEID assigned to a communication tunnel of the SGW in response to the request receiving unit receiving the session generation request, a registration unit that registers the session information generated by the session information generating unit in the storage unit, and a response transmitting unit that transmits a session generation response of the communication terminal to the SGW in response to the session information generating unit generating the session information. The SGW may further include a response receiving unit that receives the session generation response, and a data transmitting unit that transmits uplink data of the communication terminal to a PGW selected as a transmission target of the uplink data from among the multiple PGWs based on the PGW selection condition after the response receiving unit receives the session generation response.The PGW selected as the transmission target of the uplink data may have a first data receiving unit that receives the uplink data, and a first session information acquisition unit that acquires the session information from the memory unit when the first data receiving unit receives the uplink data and the PGW does not retain the session information.

[0004] In the system, the PGW selected as the transmission target of the uplink data may be the same PGW as the PGW selected as the transmission target of the session generation request.

[0005] In any of the above systems, the PGW selected as the transmission target of the uplink data may be a PGW different from the PGW selected as the transmission target of the session generation request.

[0006] In any of the above systems, the PGW selected as the transmission target of the session generation request may be located in the network of a first country, and the PGW selected as the transmission target of the uplink data may be located in the network of a second country different from the first country.

[0007] In any of the systems described above, the first session information acquisition unit may acquire the session information from the storage unit when the first data receiving unit receives the uplink data for the first time.

[0008] In any of the above systems, a PGW among the multiple PGWs to which downlink data of the communication terminal is to be transmitted may have a second data receiving unit that receives the downlink data, and a second session information acquisition unit that acquires the session information from the memory unit when the second data receiving unit receives the downlink data and the PGW does not retain the session information.

[0009] In any of the above systems, the SGW may be separated into an SGW-C (SGW-Control plane function) and an SGW-U (SGW-User plane function), and each of the plurality of PGWs may be a PGW-C (PGW-Control plane function) and a PGW-U (PGW-User plane function). the PGW-C is assigned the same IP address and the PGW-U is assigned the same IP address, the IP address of the PGW may include the IP address of the PGW-C and the IP address of the PGW-U that is different from the IP address of the PGW-C, the TEIDs assigned to the communication tunnels of the respective PGWs may include the TEID assigned to the communication tunnels of the respective PGW-Cs and the TEIDs assigned to the communication tunnels of the respective PGW-Us and different from the TEIDs assigned to the communication tunnels of the respective PGW-Cs, the IP address of the SGW may include the IP address of the SGW-C and the IP address of the SGW-U that is different from the IP address of the SGW-C, and the TEIDs assigned to the communication tunnels of the respective SGWs may include the TEID assigned to the communication tunnels of the respective SGW-Cs and the TEIDs assigned to the communication tunnels of the respective SGW-Us and different from the TEIDs assigned to the communication tunnels of the respective SGW-Cs.

[0010] In any of the above systems, the memory unit may be located on a cloud, and each of the multiple PGWs may be able to access the memory unit.

[0011] According to an embodiment of the present invention, a system is provided. The system may include a Visited Session Management Function (V-SMF). The system may include a Visited User Plane Function (V-UPF) that is located in a network in which the V-SMF is located. The system may include a plurality of Home Session Management Functions (H-SMFs). The system may include a plurality of Home User Plane Functions (H-UPFs). The system may include a storage unit. Each H-SMF of the plurality of H-SMFs may be located in a network having a different ASN, and each H-SMF may be assigned the same IP address. Each H-UPF of the plurality of H-UPFs may be located in a network having a different ASN, and each H-UPF may be assigned the same IP address. The V-SMF may include a request transmission unit that transmits a session generation request of a communication terminal requesting generation of a session to a PDN to an H-SMF selected from the plurality of H-SMFs as a transmission target of the session generation request based on a predetermined H-SMF selection condition.The H-SMF selected as the transmission target of the session creation request includes a request receiving unit that receives the session creation request, and in response to the request receiving unit receiving the session creation request, the request receiving unit receives an IP address of the communication terminal, the IP address of the H-SMF, the IP address of the H-UPF that is different from the IP address of the H-SMF, a TEID assigned to a communication tunnel of each of the H-SMFs, a TEID that is assigned to a communication tunnel of each of the H-UPFs and is different from the TEID assigned to the communication tunnel of each of the H-SMFs, an IP address of the V-SMF, and a V-SMF. The communication terminal may include a session information generating unit configured to generate session information of the communication terminal, the session information including an IP address of the V-UPF different from the IP address of the V-SMF, a TEID assigned to a communication tunnel of the V-SMF, and a TEID assigned to the communication tunnel of the V-UPF and different from the TEID assigned to the communication tunnel of the V-SMF, a registration unit configured to register the session information generated by the session information generating unit in the storage unit, and a response transmitting unit configured to transmit a session generation response of the communication terminal to the V-SMF in response to the session information generating unit generating the session information. The V-SMF may further include a response receiving unit that receives the session generation response. The V-UPF may include a data transmitting unit that transmits uplink data of the communication terminal to an H-UPF selected from the plurality of H-UPFs as a transmission target of the uplink data based on a predetermined H-UPF selection condition after the V-SMF receives the session generation response. The H-UPF selected as the transmission target of the uplink data may have a data receiving unit that receives the uplink data, and a session information acquisition unit that acquires the session information from the memory unit when the data receiving unit receives the uplink data and the H-UPF does not retain the session information.

[0012] According to one embodiment of the present invention, there is provided a method executed by a system including an SGW, a plurality of PGWs, and a storage unit, in which each of the plurality of PGWs is located in a network having a different ASN and each of the PGWs is assigned the same IP address. The method may include a request transmission step in which the SGW transmits a session generation request of a communication terminal requesting generation of a session to a PDN to a PGW selected from the plurality of PGWs as a transmission target of the session generation request based on a predetermined PGW selection condition. The method may include a request reception step in which the PGW selected as the transmission target of the session generation request receives the session generation request. The method may include a session information generation step in which the PGW selected as the transmission target of the session generation request receives the session generation request in response to receiving the session generation request in the request reception step, the PGW selected as the transmission target of the session generation request generates session information of the communication terminal including an IP address of the communication terminal, the IP address of the PGW, a TEID assigned to a communication tunnel of each of the PGWs, an IP address of the SGW, and a TEID assigned to a communication tunnel of the SGW. The method may include a registration step in which the PGW selected as the transmission target of the session generation request registers the session information generated in the session information generation step in the storage unit. The method may include a response transmission step in which the PGW selected as the transmission target of the session generation request transmits a session generation response of the communication terminal to the SGW in response to the session information being generated in the session information generation step. The method may include a response reception step in which the SGW receives the session generation response. The method may include a data transmission step in which the SGW transmits uplink data of the communication terminal to a PGW selected as a transmission target of the uplink data from among the multiple PGWs based on the PGW selection condition after receiving the session generation response in the response reception step. The method may include a data reception step in which the PGW selected as the transmission target of the uplink data receives the uplink data.The method may include a session information acquisition step of acquiring the session information from the memory unit when the PGW selected as the transmission target of the uplink data receives the uplink data in the data reception step and the PGW does not hold the session information.

[0013] According to one embodiment of the present invention, there is provided a method executed by a system including a V-SMF, a V-UPF arranged in a network in which the V-SMF is arranged, a plurality of H-SMFs, a plurality of H-UPFs, and a storage unit, wherein each H-SMF of the plurality of H-SMFs is arranged in a network with a different ASN and each H-SMF is assigned the same IP address, and each H-UPF of the plurality of H-UPFs is arranged in a network with a different ASN and each H-UPF is assigned the same IP address. The method may include a request transmission step in which the V-SMF transmits a session creation request of a communication terminal requesting to create a session to a PDN to an H-SMF selected from the plurality of H-SMFs as a destination of the session creation request based on a predetermined H-SMF selection condition. The method may include a request reception step in which the H-SMF selected as the destination of the session creation request receives the session creation request. The method may include a session information generation step in which, in response to the H-SMF selected as the transmission target of the session generation request receiving the session generation request in the request receiving step, generates session information of the communication terminal, including an IP address of the communication terminal, the IP address of the H-SMF, the IP address of the H-UPF that is different from the IP address of the H-SMF, a TEID assigned to the communication tunnel of each H-SMF, a TEID assigned to the communication tunnel of each H-UPF and different from the TEID assigned to the communication tunnel of each H-SMF, an IP address of the V-SMF, an IP address of the V-UPF that is different from the IP address of the V-SMF, a TEID assigned to the communication tunnel of the V-SMF, and a TEID assigned to the communication tunnel of the V-UPF and different from the TEID assigned to the communication tunnel of the V-SMF. The method may include a registration step in which the H-SMF selected as the transmission target of the session generation request registers the session information generated in the session information generation step in the memory unit.The method may include a response transmission step in which the H-SMF selected as the transmission target of the session creation request transmits a session creation response of the communication terminal to the V-SMF in response to the session information being generated in the session information generation step. The method may include a response reception step in which the V-SMF receives the session creation response. The method may include a data transmission step in which the V-UPF transmits uplink data of the communication terminal to an H-UPF selected as a transmission target of the uplink data from among the plurality of H-UPFs based on a predetermined H-UPF selection condition after the V-SMF receives the session creation response in the response reception step. The method may include a data reception step in which the H-UPF selected as the transmission target of the uplink data receives the uplink data. The method may include a session information acquisition step in which, when the H-UPF selected as the transmission target of the uplink data receives the uplink data in the data reception step and the H-UPF does not hold the session information, the session information acquisition step is performed to acquire the session information from the storage unit.

[0014] The above summary of the invention does not list all of the necessary features of the present invention. Also, subcombinations of these features may also be inventions. [Brief description of the drawings]

[0015] [Figure 1] An example of a system 10 is shown diagrammatically. [Diagram 2] FIG. 2 is an explanatory diagram for explaining an example of a processing flow of the system 10. [Diagram 3] Another example of the system 10 is shown diagrammatically. [Figure 4] Another example of the system 10 is shown diagrammatically. [Diagram 5] 11 is an explanatory diagram for explaining another example of the processing flow of the system 10. FIG. [Figure 6] 2 illustrates an example of a functional configuration of the PGW 100. [Figure 7] 2 illustrates an example of a functional configuration of the SGW 300. [Figure 8] Another example of the system 10 is shown diagrammatically. [Figure 9] 11 is an explanatory diagram for explaining another example of the processing flow of the system 10. FIG. [Figure 10] Another example of the system 10 is shown diagrammatically. [Figure 11] Another example of the system 10 is shown diagrammatically. [Figure 12] 11 is an explanatory diagram for explaining another example of the processing flow of the system 10. FIG. [Figure 13] 2 shows an example of a functional configuration of the H-SMF 420. [Figure 14] 2 shows an example of a functional configuration of the H-UPF 440. [Figure 15] 2 shows an example of a functional configuration of the V-SMF 620. [Figure 16] 2 shows an example of a functional configuration of the V-UPF 640. [Figure 17] An example of the hardware configuration of a computer 1200 functioning as a PGW 100, an SGW 300, an H-SMF 420, an H-UPF 440, a V-SMF 620, or a V-UPF 640 is shown in schematic form. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0016] When communicating in a Home Routed system in international roaming, in the case of LTE (Long Term Evolution) communication, a session is generated from an SGW on a VPLMN (Visited Public Land Mobile Network) side to a specific PGW on a HPLMN (Home Public Land Mobile Network) side and a GTP (GPRS Tunneling Protocol) tunnel is generated. The system according to this embodiment employs a mechanism in which, for example, the same IP address is assigned to each PGW of a plurality of geographically different HPLMNs using IP Anycast, and the PGW on the HPLMN side present at a site selected by a best path selection algorithm of BGP (Border Gateway Protocol) acquires session information triggered by receiving a first packet of a communication terminal from the SGW and processes the packet of the communication terminal. By configuring the PGW on the HPLMN side present at a site selected by the best path selection algorithm to acquire session information only, the PGW on the HPLMN side present at other sites does not need to acquire session information, and as a result, resource consumption in the entire system can be suppressed.

[0017] The present invention will be described below through embodiments of the invention, but the following embodiments do not limit the invention according to the claims. In addition, not all of the combinations of features described in the embodiments are necessarily essential to the solution of the invention.

[0018] 1 illustrates an example of a system 10. The system 10 provides mobile communication services to a user of a communication terminal 60. The system 10 provides, for example, a roaming service to a user of the communication terminal 60.

[0019] The roaming service includes, for example, an international roaming service. The roaming service includes, for example, a domestic roaming service.

[0020] The communication terminal 60 may be any communication terminal that can use the mobile communication service provided by the system 10. For example, the communication terminal 60 is a mobile phone such as a smartphone, a tablet terminal, a wearable terminal, or the like.

[0021] The mobile communication service provided by the system 10 is, for example, an LTE communication service. The mobile communication service provided by the system 10 is, for example, a 5G (5th Generation) communication service. The mobile communication service provided by the system 10 may be a 6G (6th Generation) communication service. The mobile communication service provided by the system 10 may be a 3G (3rd Generation) communication service. FIG. 1 shows an example in which the mobile communication service provided by the system 10 is an LTE communication service.

[0022] The system 10 may include a plurality of PGWs. FIG. 1 illustrates an example in which the system 10 includes two PGWs, a PGW 100 and a PGW 200. The number of PGWs included in the system 10 is not limited to two, and may be three or more. The system 10 may include an SGW 300.

[0023] The system 10 may include a router 22. The system 10 may include a database 32. The system 10 may include a router 24. The system 10 may include a database 34. The system 10 may include a router 26.

[0024] Each of the multiple PGWs is located in a network with a different ASN, and the same IP address is assigned to each PGW. For example, IP Anycast is used to assign the same IP address to each PGW.

[0025] For example, when a CUPS (Control and User Plane Separation) architecture is introduced into an LTE communication system, each of the multiple PGWs is separated into a PGW-C and a PGW-U. In this case, the same IP address is assigned to each PGW-C, and the same IP address is assigned to each PGW-U. Here, the configurations of the PGW100 and PGW200 shown in FIG. 1 will be described.

[0026] The PGW 100 has a function of relaying access to the PDN 40. The PGW 100 is disposed in, for example, an HPLMN, which is a network of a telecommunications carrier that has issued a Subscriber Identity Module (SIM) card to a user of the communication terminal 60.

[0027] The PDN 40 may include, for example, the Internet. The PDN 40 may also include any private network.

[0028] The PGW 100 is located, for example, in a network of a first country. In the example of the system 10 shown in FIG.

[0029] 1, the PGW 100 may be separated into a PGW-C 120 and a PGW-U 140. The PGW 100 does not have to be separated into a PGW-C 120 and a PGW-U 140.

[0030] The PGW 100 may be assigned an IP address. In the example of the system 10 shown in FIG. 1, the PGW-C 120 is assigned an IP address AAAA in the subnet mask 32, and the PGW-U 140 is assigned an IP address BBBB in the subnet mask 32.

[0031] The PGW 200 has a function of relaying access to the PDN 40. The PGW 200 may have the same function as the PGW 100.

[0032] The PGW200 is arranged, for example, in the HPLMN of a communication carrier that has issued a SIM card to the user of the communication terminal 60. Here, the explanation will be continued on the assumption that subscriber information of the user of the communication terminal 60, such as an International Mobile Subscriber Identity (IMSI) or an International Mobile Equipment Identity (IMEI), which is used to authenticate the user of the communication terminal 60 and is recorded in the SIM card, is synchronized in advance between the HPLMN in which the PGW100 is arranged and the HPLMN in which the PGW200 is arranged.

[0033] For example, the PGW 200 is located in a network having an ASN different from the ASN of the network in which the PGW 100 is located. For example, the PGW 200 is located in a network in a second country different from the first country. In the example of the system 10 shown in FIG. 1, the PGW 200 is located in a network in Singapore having an ASN of 65002.

[0034] The PGW 200 may be disposed in a network of a first country. For example, when the PGW 100 is disposed in a network in Tokyo, Japan, the PGW 200 may be disposed in a network in Osaka, Japan.

[0035] 1, the PGW 200 may be separated into a PGW-C 220 and a PGW-U 240. The PGW 200 does not have to be separated into a PGW-C 220 and a PGW-U 240.

[0036] The PGW 200 may be assigned an IP address. In the example of the system 10 shown in FIG. 1, the PGW-C 220 is assigned an IP address AAAA in the subnet mask 32, and the PGW-U 240 is assigned an IP address BBBB in the subnet mask 32.

[0037] The SGW300 has a function of relaying access from a wireless access network. The SGW300 is arranged, for example, in a VPLMN, which is a network of a telecommunications carrier in a location visited by the user of the communication terminal 60. The telecommunications carrier that issued a SIM card to the user of the communication terminal 60 may have a business partnership with the telecommunications carrier in a location visited by the user of the communication terminal 60. In an example of the system 10 shown in FIG. 1, the SGW300 is arranged in a network of a telecommunications carrier A in Singapore, whose ASN is 65003.

[0038] When the CUPS architecture is introduced into an LTE communication system, such as the example of the system 10 shown in FIG. 1, the SGW 300 may be separated into the SGW-C 320 and the SGW-U 340. The SGW 300 does not have to be separated into the SGW-C 320 and the SGW-U 340.

[0039] The SGW 300 may be assigned an IP address. In the example of the system 10 shown in FIG 1, the SGW-C 320 is assigned an IP address CCCC in the subnet mask 32, and the SGW-U 340 is assigned DDDD in the subnet mask 32.

[0040] The router 22 has a function of relaying data. The router 22 relays, for example, uplink data. The router 22 relays, for example, downlink data.

[0041] The router 22 is disposed, for example, in the HPLMN in which the PGW 100 is disposed. The router 22 may be separate from the PGW 100 or may be integrated with the PGW 100.

[0042] The router 24 has a function of relaying data. The router 24 has the same function as the router 22.

[0043] The router 24 is disposed, for example, in the HPLMN in which the PGW 200 is disposed. The router 24 may be separate from the PGW 200 or may be integrated with the PGW 200.

[0044] The router 26 has a function of relaying data. The router 26 relays, for example, uplink data. The router 26 relays, for example, downlink data.

[0045] The router 26 is disposed, for example, in a VPLMN in which the SGW 300 is disposed. The router 26 may be separate from the SGW 300 or may be integrated with the SGW 300.

[0046] For example, route information between organizations is exchanged among the router 22, the router 24, and the router 26 in accordance with BGP. For example, in response to a change in the route information, the route information is exchanged among the router 22, the router 24, and the router 26. The route information may also be exchanged periodically among the router 22, the router 24, and the router 26.

[0047] The route information includes, for example, the ASN of the network in which the router is located. The route information includes, for example, an IP address assigned to a device located in the network. The route information may include a subnet mask of the IP address assigned to the device located in the network. The subnet mask is expressed, for example, in prefix notation.

[0048] The router 22 advertises the route information, for example, to the router 26. The router 22 may also advertise the route information to an IPX (IP exchange) that relays between the HPLMN and the VPLMN. The router 24 may advertise the route information in the same manner as the router 22.

[0049] In the example of the system 10 shown in Fig. 1, the router 22 advertises ASN=65001, the IP address of the PGW-C 120=AAAA / 32, and the IP address of the PGW-U 140=BBBB / 32. Also, in the example of the system 10 shown in Fig. 1, the router 24 advertises ASN=65002, the IP address of the PGW-C 220=AAAA / 32, and the IP address of the PGW-U 240=BBBB / 32.

[0050] For example, the router 26 advertises the route information toward the router 22 and the router 24. The router 22 may advertise the route information toward IPX. In the example of the system 10 shown in Fig. 1, the router 26 advertises ASN=65003, IP address of the SGW-C320=CCCC / 32, and IP address of the SGW-U340=DDDD / 32.

[0051] The router 26 generates, for example, a route table. The router 26 generates the route table based on, for example, the route information advertised by each of the router 22 and the router 24. The router 26 generates the route table by, for example, associating the ASN of the network in which the router is located with the IP address assigned to the device located in the network. In an example of the system 10 shown in FIG. 1, the router 26 generates a route table including ASN=65001 and IP address=AAAA / 32 of the PGW-C120, ASN=65001 and IP address=BBBB / 32 of the PGW-U140, ASN=65002 and IP address=AAAA / 32 of the PGW-C220, and ASN=65002 and IP address=BBBB / 32 of the PGW-U240.

[0052] The SGW300 receives, for example, a session creation request for requesting the creation of a session to the PDN40 of the communication terminal 60 of a user visiting the VPLMN. The session creation request includes, for example, an IP address of the communication terminal 60. The session creation request includes, for example, an IMSI of the communication terminal 60. The session creation request includes, for example, an APN (Access Point Name) of the communication terminal 60. The session creation request includes, for example, an IP address of the SGW300. For example, when the SGW300 is separated into the SGW-C320 and the SGW-U340, the IP address of the SGW300 includes an IP address of the SGW-C320 and an IP address of the SGW-U340 that is different from the IP address of the SGW-C320. The session creation request includes, for example, a TEID assigned to a communication tunnel of the SGW300. For example, when the SGW 300 is separated into the SGW-C 320 and the SGW-U 340, the TEID assigned to the communication tunnel of the SGW 300 includes the TEID assigned to the communication tunnel of the SGW-C 320 and the TEID assigned to the communication tunnel of the SGW-U 340 and different from the TEID assigned to the communication tunnel of the SGW-C 320. When the SGW 300 is not separated into the SGW-C 320 and the SGW-U 340, the TEID assigned to the communication tunnel of the U-Plane (User-Plane) function of the SGW 300 may be the same as or different from the TEID assigned to the communication tunnel of the C-Plane (Control-Plane) function of the SGW 300. The session creation request includes, for example, the IP address of the PGW included in the system 10. For example, when each of the multiple PGWs included in the system 10 is separated into a PGW-C and a PGW-U, the IP address of the PGW included in the system 10 includes the IP address of the PGW-C and the IP address of the PGW-U that is different from the IP address of the PGW-C. The session creation request may include any other information for creating a session to the PDN 40 of the communication terminal 60.

[0053] The SGW 300 may use the router 26 to transmit the received session creation request of the communication terminal 60. The router 26 may select a PGW to which the session creation request of the communication terminal 60 is to be transmitted from among a plurality of PGWs included in the system 10, based on predetermined PGW selection conditions.

[0054] For example, the router 26 selects a PGW having a route with the shortest distance to the SGW 300 from among the multiple PGWs included in the system 10 as the PGW to which a session creation request from the communication terminal 60 is to be transmitted. For example, when there are multiple PGWs to which the same IP address is assigned, the router 26 selects a PGW having a route with the shortest distance to the SGW 300 from among the multiple PGWs to which the same IP address is assigned as the PGW to which a session creation request from the communication terminal 60 is to be transmitted, in accordance with the best path selection algorithm of BGP, based on the generated route table.

[0055] In the example of the system 10 shown in FIG. 1, the route from the PGW 100 to the SGW 300 passes through a network 12 constructed in Tokyo and a network 14 constructed in Singapore. In contrast, the route from the PGW 200 to the SGW 300 passes only through the network 14. Therefore, in the example of the system 10 shown in FIG. 1, when the SGW 300 is in a state in which it can transmit a session creation request of the communication terminal 60 to both the PGW 100 and the PGW 200 using the router 26, the distance of the route from the PGW 200 to the SGW 300 is shorter than the distance of the route from the PGW 100 to the SGW 300, so the router 26 selects the PGW 200 from the PGW 100 and the PGW 200 as the PGW to which the session creation request of the communication terminal 60 is to be transmitted. Here, the explanation will be continued assuming that the router 26 selects the PGW 200 as the PGW to which the session creation request of the communication terminal 60 is to be transmitted.

[0056] The SGW 300 may use the router 26 to transmit the session generation request of the communication terminal 60 to the PGW 200 via the network 14. The PGW 200 may use the router 24 to receive the session generation request of the communication terminal 60 via the network 14. The PGW 200 may be an example of a PGW selected as a transmission target of the session generation request of the communication terminal 60.

[0057] The PGW 200 may generate session information of the communication terminal 60 in response to receiving a session generation request for the communication terminal 60 from the SGW 300. The session information includes, for example, an IP address of the communication terminal 60. The session information includes, for example, an IMSI of the communication terminal 60. The session information includes, for example, an IP address of a PGW included in the system 10. The session information includes, for example, a TEID assigned to a communication tunnel of each PGW of a plurality of PGWs included in the system 10. For example, when each PGW is separated into a PGW-C and a PGW-U, the TEID assigned to the communication tunnel of each PGW includes a TEID assigned to the communication tunnel of each PGW-C and a TEID assigned to the communication tunnel of each PGW-U and different from the TEID assigned to the communication tunnel of each PGW-C. When each PGW is not separated into a PGW-C and a PGW-U, the TEID assigned to the communication tunnel of the U-Plane function of each PGW may be the same as or different from the TEID assigned to the communication tunnel of the C-Plane function of each PGW. The session information includes, for example, the IP address of the SGW 300. The session information includes, for example, the TEID assigned to the communication tunnel of the SGW 300. The session information may include any other information for generating a session to the PDN 40 of the communication terminal 60.

[0058] The PGW 200 may register the generated session information of the communication terminal 60 in the database 34 corresponding to the PGW 200. The PGW 200 may store, for example, the IP address of the database 34 in advance.

[0059] The database 34 includes, for example, a message queue that temporarily stores session information of the communication terminal 60. The database 34 may be an example of a storage unit.

[0060] The database 34 may be separate from the PGW 200. The database 34 may be integrated with the PGW 200.

[0061] The database 34 is disposed, for example, in a network in which the PGW 200 is disposed. The database 34 may be disposed in a network of an ASN different from the ASN of the network in which the PGW 200 is disposed.

[0062] The database 34 may synchronize the session information of the registered communication terminal 60 between the database 34 and the database 32 corresponding to the PGW 100. The database 32 may be an example of a storage unit.

[0063] The database 34 uses, for example, a Pub / Sub (Publish / Subscribe) method to synchronize the session information of the communication terminal 60 between the database 34 and the database 32. In this case, the database 34 may be a publisher, and the database 32 may be a subscriber.

[0064] For example, the database 34 sends a message including session information of the communication terminal 60 to a topic. The database 32 obtains the session information of the communication terminal 60 by receiving a message from a subscription corresponding to the topic to which the message was sent by the database 34. In this way, the session information of the communication terminal 60 is synchronized between the database 34 and the database 32.

[0065] The database 32 may be separate from the PGW 100. The database 32 may be integrated with the PGW 100.

[0066] The database 32 is disposed, for example, in a network in which the PGW 100 is disposed. The database 32 may be disposed in a network of an ASN different from the ASN of the network in which the PGW 100 is disposed.

[0067] In response to generating the session information of the communication terminal 60, the PGW 200 may use the router 24 to transmit a session generation response of the communication terminal 60 to the SGW 300 via the network 14 in response to the session generation request of the communication terminal 60. The session generation response includes, for example, an IP address of a PGW included in the system 10. The session generation response includes, for example, a TEID assigned to a communication tunnel of each PGW of the multiple PGWs included in the system 10. The session generation response may include any other information for generating a session to the PDN 40 of the communication terminal 60.

[0068] The SGW 300 may use the router 26 to receive the session creation response of the communication terminal 60 via the network 14. This allows the SGW 300 to create a session for the communication terminal 60 to the PDN 40 based on the session creation response of the communication terminal 60.

[0069] Thereafter, the SGW 300 may receive the uplink data of the communication terminal 60 from the communication terminal 60. The SGW 300 may transmit the received uplink data of the communication terminal 60 using the router 26.

[0070] The router 26 selects, for example, based on the PGW selection conditions, a PGW to which uplink data of the communication terminal 60 is to be transmitted from among the multiple PGWs included in the system 10. For example, when there are multiple PGWs to which the same IP address is assigned, the router 26 selects, based on the generated route table and in accordance with the best path selection algorithm of BGP, a PGW having the shortest distance to the SGW 300 as a PGW to which uplink data of the communication terminal 60 is to be transmitted.

[0071] 1, when the SGW300 is in a state in which it can transmit uplink data of the communication terminal 60 to both the PGW100 and the PGW200 using the router 26, the router 26 selects the PGW200 from the PGW100 and the PGW200 as the PGW to which the uplink data of the communication terminal 60 is to be transmitted. Here, the explanation will be continued assuming that the router 26 has selected the PGW200 as the PGW to which the uplink data of the communication terminal 60 is to be transmitted.

[0072] The SGW 300 may transmit uplink data of the communication terminal 60 to the PGW 200 via the network 14 using the router 26. The PGW 200 may receive the uplink data of the communication terminal 60 via the network 14 using the router 24. The PGW 200 may be an example of a PGW selected as a transmission target of the uplink data of the communication terminal 60.

[0073] When PGW 200 receives uplink data of communication terminal 60 and does not hold session information of communication terminal 60, it acquires the session information of communication terminal 60 from database 34 and processes the data of communication terminal 60 based on the session information of communication terminal 60 acquired from database 34. On the other hand, when PGW 200 receives uplink data of communication terminal 60 and holds session information of communication terminal 60, it processes the data of communication terminal 60 based on the session information of communication terminal 60 that it holds.

[0074] For example, the PGW 200 processes data of the communication terminal 60 by transmitting uplink data of the communication terminal 60 to the PDN 40. The PGW 200 may process data of the communication terminal 60 by transmitting downlink data of the communication terminal 60 received via the PDN 40 to the communication terminal 60.

[0075] For example, when the state of at least one of the multiple PGWs included in the system 10 changes, such as when a failure occurs in one of the multiple HPLMNs included in the system 10 or when maintenance of the PGW starts, the router 26 updates the route table. Based on the updated route table, the router 26 may select a PGW to which the communication terminal 60 transmits uplink data from among the multiple PGWs included in the system 10 in accordance with the best path selection algorithm of BGP.

[0076] 1, in a case where the SGW300 is transmitting uplink data of the communication terminal 60 to the PGW200 using the router 26, if the state where the SGW300 can transmit the uplink data of the communication terminal 60 to both the PGW100 and the PGW200 using the router 26 changes to a state where the SGW300 can transmit the uplink data of the communication terminal 60 only to the PGW100 using the router 26, the router 26 may update the route table. After that, the router 26 may select the PGW100 as the PGW to which the uplink data of the communication terminal 60 is to be transmitted based on the updated route table.

[0077] The SGW 300 may transmit uplink data of the communication terminal 60 to the PGW 100 via the networks 14 and 12 using the router 26. The PGW 100 may receive uplink data of the communication terminal 60 via the networks 14 and 12 using the router 22. The PGW 100 may be an example of a PGW selected as a transmission target of the uplink data of the communication terminal 60.

[0078] When the PGW 100 receives uplink data of the communication terminal 60 but does not hold session information of the communication terminal 60, the PGW 100 acquires, from the database 32, the session information of the communication terminal 60 that is synchronized between the database 32 and the database 34, and processes the data of the communication terminal 60 based on the session information of the communication terminal 60 acquired from the database 32. On the other hand, when the PGW 100 receives uplink data of the communication terminal 60 but holds session information of the communication terminal 60, the PGW 100 processes the data of the communication terminal 60 based on the session information of the communication terminal 60 that it holds.

[0079] 1, when data of the communication terminal 60 is communicated on a path between the communication terminal 60 and the PDN 40 via the SGW 300 and the PGW 200, the data of the communication terminal 60 is communicated by domestic roaming. On the other hand, in the example of the system 10 shown in FIG 1, when data of the communication terminal 60 is communicated on a path between the communication terminal 60 and the PDN 40 via the SGW 300 and the PGW 100, the data of the communication terminal 60 is communicated by international roaming.

[0080] In the example of the system 10 shown in FIG. 1, if the SGW 300 is in a state in which it can transmit the session generation request of the communication terminal 60 only to the PGW 100 using the router 26 at the timing when the SGW 300 transmits the session generation request of the communication terminal 60, the router 26 selects the PGW 100 as the PGW to which the session generation request of the communication terminal 60 is to be transmitted. In this case, the SGW 300 may transmit the session generation request of the communication terminal 60 to the PGW 100 via the networks 14 and 12 using the router 26. The PGW 100 may receive the session generation request of the communication terminal 60 via the networks 14 and 12 using the router 22. The PGW 100 may be an example of a PGW selected as the transmission target of the session generation request of the communication terminal 60.

[0081] In response to receiving a session creation request from the SGW 300, the PGW 100 may generate session information of the communication terminal 60. The PGW 100 may register the generated session information of the communication terminal 60 in the database 32. The PGW 100 may store, for example, an IP address of the database 32 in advance.

[0082] The database 32 may have the same function as the database 34. For example, when the PGW 100 registers the session information of the communication terminal 60 in the database 32, the database 32 synchronizes the session information of the communication terminal 60 between the database 32 and the database 34 in the same manner as the database 34.

[0083] 1, a communications carrier that has issued a SIM card to a user of the communications terminal 60 may establish an HPLMN at three or more bases. In this case, the same IP address may be assigned to the PGW at each of the three or more bases.

[0084] Conventionally, each PGW of HPLMN constructed at multiple sites by a telecommunications carrier providing a roaming service is assigned a different IP address using IP Unicast. Therefore, when a session is generated between an SGW of a VPLMN and a PGW of a HPLMN, an MME (Mobility Management Entity) corresponding to the SGW of the VPLMN must select one PGW from multiple PGWs of the HPLMN with different IP addresses. As a result, when a session is generated between an SGW of a VPLMN and a PGW of a HPLMN whose distance to the SGW of the VPLMN is long, there is a possibility that a communication delay will occur in the communication terminal. In particular, in a situation where a telecommunications carrier providing an international roaming service constructs an HPLMN in a first country and a second country, when a session is generated between an SGW of a VPLMN in the second country and a PGW of a HPLMN in the first country, unnecessary international communication is required when a session is generated between an SGW of a VPLMN in the second country and a PGW of a HPLMN in the second country, so that the possibility of a communication delay in the communication terminal is further increased.

[0085] In contrast, according to the system 10 shown in Fig. 1, the same IP address is assigned to each PGW of the HPLMN constructed at multiple locations by a communications carrier providing a roaming service, using IP Anycast. The SGW 300 of the VPLMN transmits a session generation request of the communications terminal 60 to a PGW selected as a PGW of the HPLMN to which the session generation request of the communications terminal 60 is to be transmitted based on the PGW selection conditions, and transmits uplink data of the communications terminal 60 to a PGW selected as a PGW of the HPLMN to which the uplink data of the communications terminal 60 is to be transmitted based on the PGW selection conditions. This allows the SGW 300 to preferentially transmit the session generation request of the communications terminal 60 and the uplink data of the communications terminal 60 to a PGW that is closer to the SGW 300, so that the system 10 shown in Fig. 1 contributes to realizing an LTE communications service in which the occurrence of communication delays of the communications terminal 60 is suppressed. Then, the PGW that receives a session generation request for the communication terminal 60 from the SGW 300 generates session information for the communication terminal 60 and registers the generated session information for the communication terminal 60 in a database corresponding to the PGW. The database in which the session information for the communication terminal 60 is registered synchronizes the session information for the communication terminal 60 with databases corresponding to other PGWs. After that, if the PGW that receives the uplink data for the communication terminal 60 from the SGW 300 does not hold the session information for the communication terminal 60, it processes the data for the communication terminal 60 based on the session information for the communication terminal 60 acquired from the database corresponding to the PGW, and if it holds the session information for the communication terminal 60, it processes the data for the communication terminal 60 based on the session information for the communication terminal 60 that it holds. In this way, by adopting a configuration in which the PGW that receives the uplink data for the communication terminal 60 from the SGW 300 does not hold the session information for the communication terminal 60 as a trigger to acquire the session information for the communication terminal 60 from the database, the PGW that does not process the data for the communication terminal 60 does not need to acquire the session information for the communication terminal 60. As a result, the system 10 shown in FIG. 1 contributes to realizing LTE communication services with reduced consumption of communication resources.

[0086] 2 is an explanatory diagram for explaining an example of the flow of processing in the system 10. Here, the description will be given assuming that a state in which the user of the communication terminal 60 has visited a VPLMN is a starting state.

[0087] In step (step may be abbreviated as S) 102, the SGW-C320 transmits a session generation request of the communication terminal 60 requesting generation of a session to the PDN 40. The SGW-C320 transmits the session generation request of the communication terminal 60 received from, for example, the MME corresponding to the SGW300 that has accepted the attach request from the communication terminal 60 and performed authentication processing of the communication terminal 60. Here, the explanation will be continued assuming that the SGW-C320 is in a state in which it can transmit the session generation request of the communication terminal 60 to both the PGW-C120 and the PGW-C220 using the router 26, the router 26 selects the PGW-C220 as the PGW-C to which the session generation request of the communication terminal 60 is to be transmitted based on a predetermined PGW-C selection condition, and the SGW-C320 transmits the session generation request of the communication terminal 60 to the PGW-C220 using the router 26.

[0088] The PGW-C 220 receives a session creation request for the communication terminal 60 from the SGW-C 320. The PGW-C 220 may create session information for the communication terminal 60 based on the received session creation request for the communication terminal 60.

[0089] In S104, the PGW-C 220 registers the generated session information of the communication terminal 60 in the database 34. In S106, the database 34 synchronizes the session information of the communication terminal 60 registered by the PGW-C 220 in S104 between the database 34 and the database 32.

[0090] In S108, the PGW-C 220 transmits to the SGW-C 320 a create session response of the communication terminal 60 in response to the session creation request of the communication terminal 60. The SGW-C 320 receives the create session response of the communication terminal 60 from the PGW-C 220. The SGW-C 320 may store the received create session response of the communication terminal 60 so that the SGW-C 320 and the SGW-U 340 can use the create session response of the communication terminal 60.

[0091] In S110, the SGW-U340 transmits uplink data of the communication terminal 60 based on the session creation response of the communication terminal 60 received by the SGW-C320 in S108. Here, the explanation will be continued assuming that the SGW-U340 is in a state in which it can transmit the uplink data of the communication terminal 60 to both the PGW-U140 and the PGW-U240 using the router 26, the router 26 selects the PGW-U240 as the PGW-U to which the uplink data of the communication terminal 60 is to be transmitted based on predetermined PGW-U selection conditions, the SGW-U340 transmits the uplink data of the communication terminal 60 to the PGW-U240 using the router 26, and the PGW-U240 does not hold session information of the communication terminal 60.

[0092] In S112, since the PGW-U 240 does not hold session information of the communication terminal 60 for processing the uplink data of the communication terminal 60 received in S110, the PGW-U 240 acquires the session information of the communication terminal 60 from the database 34. The PGW-U 240 processes the data of the communication terminal 60 based on the session information of the communication terminal 60 acquired from the database 34.

[0093] In S114, maintenance work is started on the PGW-U 240. In response to the start of the maintenance work on the PGW-U 240, the router 26 may update the route table.

[0094] In S116, the SGW-U340 transmits uplink data of the communication terminal 60 based on the session creation response of the communication terminal 60 received by the SGW-C320 in S108. Here, the explanation will be continued assuming that the SGW-U340 is in a state in which it can transmit the uplink data of the communication terminal 60 only to the PGW-U140 using the router 26, that the SGW-U340 transmits the uplink data of the communication terminal 60 to the PGW-U140 using the router 26, and that the PGW-U140 does not hold session information of the communication terminal 60.

[0095] In S118, since the PGW-U 140 does not hold session information of the communication terminal 60 for processing the uplink data of the communication terminal 60 received in S116, the PGW-U 140 acquires, from the database 32, the session information of the communication terminal 60 that was synchronized between the database 32 and the database 34 in S106. The PGW-U 140 processes the data of the communication terminal 60 based on the session information of the communication terminal 60 acquired from the database 32.

[0096] 3 is a schematic diagram of another example of the system 10. Here, differences from the system 10 shown in FIG. 1 will be mainly described.

[0097] The PGW-C 120 may be located on a cloud. The PGW-C 120 may be located on the same network as the PDN 40, or may be located on a network different from the PDN 40. In an example of the system 10 shown in FIG. 3, the PGW-C 120 is located in region 1 on a cloud with an ASN of 65001.

[0098] The PGW-C 220 may be located on a cloud. The PGW-C 220 may be located on the same network as the PDN 40, or may be located on a network different from the PDN 40. In one example of the system 10 shown in FIG. 3, the PGW-C 220 is located in region 2 on a cloud with an ASN of 65002.

[0099] The system 10 may further include a database 48 that is located on a cloud. The database 48 may be located on the same network as the PDN 40, or may be located on a different network from the PDN 40. The database 48 may be an example of a storage unit.

[0100] Each of the multiple PGWs included in the system 10 may be able to access the database 48. Each PGW may access the database 48, for example, via the PDN 40. Each PGW may also access the database 48 directly.

[0101] The PGW-C of the PGW selected as the transmission target of the session generation request of the communication terminal 60 may register the generated session information of the communication terminal 60 in the database 48. If the PGW does not hold the session information of the communication terminal 60, the PGW-U of the PGW selected as the transmission target of the uplink data of the communication terminal 60 may acquire the session information of the communication terminal 60 from the database 48 and process the data of the communication terminal 60 based on the session information of the communication terminal 60 acquired from the database 48.

[0102] The system 10 may further include a resource management device 700 that manages physical resources on the cloud. The resource management device 700 manages the physical resources on the cloud, for example, by allocating the physical resources on the cloud to each of the multiple PGW-Cs included in the system 10.

[0103] The physical resources include, for example, a central processing unit (CPU). The physical resources include, for example, a memory. The physical resources may include any other components used in processing related to mobile communication services.

[0104] The resource management device 700 determines the amount of physical resources on the cloud to be allocated to each PGW-C based on, for example, the load status of each PGW-C. The resource management device 700 determines the amount of physical resources on the cloud to be allocated to each PGW-C, for example, so as to allocate a larger amount of resources to a PGW-C that receives a larger number of session generation requests per unit time. The resource management device 700 determines the amount of physical resources on the cloud to be allocated to each PGW-C, for example, so as to allocate a larger amount of resources to a PGW-C that has a larger amount of traffic per unit time. The resource management device 700 may determine the amount of physical resources on the cloud to be allocated to each PGW-C, for example, so as to allocate a larger amount of resources to a PGW-C that has a slower processing speed.

[0105] The resource management device 700 transmits, for example, resource amount information indicating the amount of physical resources on the cloud to be allocated to each PGW-C to each PGW-C. The resource management device 700 transmits the resource amount information to each PGW-C via, for example, the PDN 40.

[0106] Each PGW-C may receive resource amount information from resource management device 700. Each PGW-C may use the physical resources on the cloud allocated by resource management device 700 to execute processing related to mobile communication services.

[0107] The resource management device 700 changes the resource amount of the physical resources on the cloud to be allocated to each PGW-C, for example, based on the usage status of the physical resources on the cloud. The resource management device 700 changes the resource amount of the physical resources on the cloud to be allocated to each PGW-C, for example, based on the usage rate of the CPU on the cloud. The resource management device 700 changes the resource amount of the physical resources on the cloud to be allocated to each PGW-C, for example, when the usage rate of the CPU on the cloud exceeds a predetermined CPU usage rate threshold. The resource management device 700 may change the resource amount of the physical resources on the cloud to be allocated to each PGW-C, for example, when the usage rate of the CPU on the cloud falls below a predetermined CPU usage rate threshold. The resource management device 700 may change the resource amount of the physical resources on the cloud to be allocated to each PGW-C, for example, based on the usage rate of the memory on the cloud. The resource management device 700 changes the resource amount of the physical resources on the cloud to be allocated to each PGW-C, for example, when the usage rate of the memory on the cloud exceeds a predetermined memory usage rate threshold. The resource management device 700 may change the amount of physical resources on the cloud allocated to each PGW-C when the usage rate of the memory on the cloud falls below a predetermined memory usage rate threshold. The resource management device 700 may periodically change the amount of physical resources on the cloud allocated to each PGW-C.

[0108] According to the system 10 shown in FIG. 3, the session information of the communication terminal 60 is registered in the database 48 arranged on the cloud, and the PGW selected as the transmission target of the uplink data of the communication terminal 60 acquires the session information of the communication terminal 60 from the database 48 when the PGW does not hold the session information of the communication terminal 60. Then, the PGW selected as the transmission target of the uplink data of the communication terminal 60 processes the data of the communication terminal 60 based on the session information of the communication terminal 60 acquired from the database 48. By registering the session information of the communication terminal 60 in the database 48 arranged on the cloud, it becomes unnecessary to transmit and receive the session information of the communication terminal 60 between the bases of the HPLMN in order to synchronize the session information of the communication terminal 60 between the databases arranged at the bases of the HPLMN. As a result, the system 10 shown in FIG. 3 contributes to the realization of an LTE communication service in which the consumption of communication resources is further suppressed and the risk of information leakage is further reduced.

[0109] Fig. 4 shows a schematic diagram of another example of the system 10. Here, differences from the system 10 shown in Fig. 3 will be mainly described.

[0110] The PGW-U 140 may be located on a cloud. The PGW-U 140 may be located on the same network as the PDN 40, or may be located on a network different from the PDN 40. In an example of the system 10 shown in FIG. 4, the PGW-U 140 is located in region 1 on a cloud with an ASN of 65001.

[0111] The PGW-U 240 may be located on a cloud. The PGW-U 240 may be located on the same network as the PDN 40, or may be located on a network different from the PDN 40. In an example of the system 10 shown in FIG. 4, the PGW-U 240 is located in region 2 on a cloud with an ASN of 65002.

[0112] The system 10 may further include a router 82. For example, when the PGW-C 120 is selected as a transmission target of a session generation request from the communication terminal 60, the PGW-C 120 receives the session generation request from the communication terminal 60 via the network 14, the network 12, and the router 22 using the router 82. For example, when the PGW-U 140 is selected as a transmission target of uplink data from the communication terminal 60, the PGW-U 140 receives the uplink data from the communication terminal 60 via the network 14, the network 12, and the router 22 using the router 82.

[0113] The system 10 may further include a router 84. For example, when the PGW-C 220 is selected as a transmission target of a session generation request from the communication terminal 60, the PGW-C 220 receives the session generation request from the communication terminal 60 via the network 14 and the router 24 using the router 84. For example, when the PGW-U 240 is selected as a transmission target of uplink data from the communication terminal 60, the PGW-U 240 receives the uplink data from the communication terminal 60 via the network 14 and the router 24 using the router 84.

[0114] Resource management device 700 manages physical resources on the cloud, for example, by allocating physical resources on the cloud to each of a plurality of PGW-Us included in system 10. Resource management device 700 determines the amount of physical resources on the cloud to be allocated to each PGW-U, for example, based on the load status of each PGW-U.

[0115] The resource management device 700 determines the amount of physical resources on the cloud to be allocated to each PGW-U, for example, so that a larger amount of resources is allocated to a PGW-U that receives more uplink data per unit time. The resource management device 700 determines the amount of physical resources on the cloud to be allocated to each PGW-U, for example, so that a larger amount of resources is allocated to a PGW-U that has a larger amount of traffic per unit time. The resource management device 700 determines the amount of physical resources on the cloud to be allocated to each PGW-U, for example, so that a larger amount of resources is allocated to a PGW-U that has a larger number of sessions. The resource management device 700 may determine the amount of physical resources on the cloud to be allocated to each PGW-U, for example, so that a larger amount of resources is allocated to a PGW-U that has a slower processing speed.

[0116] The resource management device 700 transmits, for example, resource amount information indicating the amount of physical resources on the cloud to be allocated to each PGW-U to each PGW-U. The resource management device 700 transmits the resource amount information to each PGW-U via, for example, the PDN 40.

[0117] Each PGW-U may receive resource amount information from resource management device 700. Each PGW-U may use physical resources on the cloud allocated by resource management device 700 to execute processing related to mobile communication services.

[0118] Resource management device 700 changes the amount of physical resources on the cloud to be allocated to each PGW-U based on the usage status of the physical resources on the cloud, for example. Resource management device 700 changes the amount of physical resources on the cloud to be allocated to each PGW-U based on the usage status of the physical resources on the cloud, in the same way as when resource management device 700 changes the amount of physical resources on the cloud to be allocated to each PGW-C based on the usage status of the physical resources on the cloud, for example. Resource management device 700 may periodically change the amount of physical resources on the cloud to be allocated to each PGW-U.

[0119] 5 is an explanatory diagram for explaining another example of the flow of processing in the system 10. Here, the description will be given assuming that a state in which the user of the communication terminal 60 has visited a VPLMN is a starting state.

[0120] In S202, the SGW-C 320 transmits a session creation request of the communication terminal 60 requesting the creation of a session to the PDN 40. Here, the explanation will be continued assuming that the SGW-C 320 is in a state in which it can transmit the session creation request of the communication terminal 60 to both the PGW-C 120 and the PGW-C 220 using the router 26, that the router 26 selects the PGW-C 220 as the PGW-C to which the session creation request of the communication terminal 60 is to be transmitted based on the PGW-C selection condition, and that the SGW-C 320 transmits the session creation request of the communication terminal 60 to the PGW-C 220 using the router 26.

[0121] The PGW-C 220 receives a session creation request for the communication terminal 60 from the SGW-C 320. The PGW-C 220 may create session information for the communication terminal 60 based on the received session creation request for the communication terminal 60.

[0122] In S204, the PGW-C 220 registers the generated session information of the communication terminal 60 in the database 48 arranged on the cloud. In S206, the PGW-C 220 transmits a session creation response of the communication terminal 60 to the SGW-C 320 in response to the session creation request of the communication terminal 60. The SGW-C 320 receives the session creation response of the communication terminal 60 from the PGW-C 220.

[0123] In S208, the SGW-U340 transmits uplink data of the communication terminal 60 based on the session creation response of the communication terminal 60 received by the SGW-C320 in S206. Here, the explanation will be continued assuming that the SGW-U340 is in a state in which it can transmit the uplink data of the communication terminal 60 to both the PGW-U140 and the PGW-U240 using the router 26, the router 26 selects the PGW-U240 as the PGW-U to which the uplink data of the communication terminal 60 is to be transmitted based on the PGW-U selection condition, the SGW-U340 transmits the uplink data of the communication terminal 60 to the PGW-U240 using the router 26, and the PGW-U240 does not hold session information of the communication terminal 60.

[0124] In S210, since the PGW-U 240 does not hold session information of the communication terminal 60 for processing the uplink data of the communication terminal 60 received in S208, the PGW-U 240 acquires the session information of the communication terminal 60 from the database 48 located on the cloud. The PGW-U 240 processes the data of the communication terminal 60 based on the session information of the communication terminal 60 acquired from the database 48.

[0125] In S212, maintenance work is started on the PGW-U 240. In response to the start of the maintenance work on the PGW-U 240, the router 26 may update the route table.

[0126] In S214, the SGW-U340 transmits uplink data of the communication terminal 60 based on the session creation response of the communication terminal 60 received by the SGW-C320 in S206. Here, the explanation will be continued assuming that the SGW-U340 is in a state in which it can transmit the uplink data of the communication terminal 60 only to the PGW-U140 using the router 26, that the SGW-U340 transmits the uplink data of the communication terminal 60 to the PGW-U140 using the router 26, and that the PGW-U140 does not hold session information of the communication terminal 60.

[0127] In S216, since the PGW-U 140 does not hold session information of the communication terminal 60 for processing the uplink data of the communication terminal 60 received in S214, the PGW-U 140 acquires the session information of the communication terminal 60 from the database 48 located on the cloud. The PGW-U 140 processes the data of the communication terminal 60 based on the session information of the communication terminal 60 acquired from the database 48.

[0128] 6 illustrates an example of a functional configuration of the PGW 100. The PGW 100 includes a request receiving unit 103, a session information generating unit 104, a storage unit 106, a registration unit 108, a session information synchronizing unit 110, a response transmitting unit 112, a data receiving unit 113, a session information acquiring unit 114, and a data transmitting unit 116. It is not essential that the PGW 100 includes all of these components.

[0129] The request receiving unit 103 receives a session creation request from the communication terminal 60 requesting the creation of a session to the PDN 40. When the PGW 100 is selected as a transmission target of the session creation request from the communication terminal 60 from among the multiple PGWs included in the system 10, the request receiving unit 103 receives the session creation request from the communication terminal 60.

[0130] The request receiving unit 103 receives the session creation request from the communication terminal 60, for example, by using a router. If the PGW 100 has a router function, the request receiving unit 103 may receive the session creation request from the communication terminal 60 by using the router function of the PGW 100.

[0131] The session information generating unit 104 generates session information of the communication terminal 60. For example, the session information generating unit 104 generates the session information of the communication terminal 60 in response to the request receiving unit 103 receiving a session generation request of the communication terminal 60. The session information generating unit 104 may store the generated session information of the communication terminal 60 in the storage unit 106.

[0132] The registration unit 108 registers in the storage unit the session information of the communication terminal 60 generated by the session information generation unit 104. For example, the registration unit 108 registers the session information of the communication terminal 60 in a database located at a base of the HPLMN. For example, the registration unit 108 registers the session information of the communication terminal 60 in a database located on a cloud.

[0133] The session information synchronization unit 110 synchronizes the session information of the communication terminal 60 registered in a database located at a base of the HPLMN by the registration unit 108 between that database and another database located at another base of the HPLMN. The session information synchronization unit 110 synchronizes the session information of the communication terminal 60 between that database and the other database using, for example, a Pub / Sub method. The session information synchronization unit 110 may also synchronize the session information of the communication terminal 60 between that database and the other database using any other method.

[0134] The response transmitting unit 112 transmits to the SGW 300 a session creation response of the communication terminal 60 in response to the session creation request of the communication terminal 60 received by the request receiving unit 103. For example, the response transmitting unit 112 transmits to the SGW 300 the session creation response of the communication terminal 60 in response to the session information generating unit 104 generating session information of the communication terminal 60. For example, the response transmitting unit 112 transmits to the SGW 300 the session creation response of the communication terminal 60 in response to the registration unit 108 registering the session information of the communication terminal 60 in the storage unit. The response transmitting unit 112 may transmit to the SGW 300 the session creation response of the communication terminal 60 in response to the session information synchronizing unit 110 synchronizing the session information of the communication terminal 60 between a database arranged at a base of the HPLMN and another database arranged at another base of the HPLMN.

[0135] The response transmitting unit 112 uses, for example, a router to transmit the create session response of the communication terminal 60. If the PGW 100 has a router function, the response transmitting unit 112 may transmit the create session response of the communication terminal 60 using the router function of the PGW 100.

[0136] The data receiving unit 113 receives data from the communication terminal 60. For example, when the PGW 100 is selected as a transmission destination of the data from the communication terminal 60 from among a plurality of PGWs included in the system 10, the data receiving unit 113 receives the data from the communication terminal 60.

[0137] The data receiving unit 113 receives uplink data of the communication terminal 60 from, for example, the SGW 300. For example, when the PGW 100 is selected as a transmission target of the uplink data of the communication terminal 60 from among a plurality of PGWs included in the system 10, the data receiving unit 113 receives the uplink data of the communication terminal 60. The data receiving unit 113 may be an example of a first data receiving unit.

[0138] The data receiving unit 113 may receive downlink data of the communication terminal 60 from a server arranged in the PDN 40. For example, when the PGW 100 is selected as a transmission target of the downlink data of the communication terminal 60 from among a plurality of PGWs included in the system 10, the data receiving unit 113 receives the downlink data of the communication terminal 60. In this case, the PDN 40 may be a private network. The data receiving unit 113 may be an example of a second data receiving unit.

[0139] The data receiving unit 113 receives the data of the communication terminal 60 by using, for example, a router. If the PGW 100 has a router function, the data receiving unit 113 may receive the data of the communication terminal 60 by using the router function of the PGW 100.

[0140] The session information acquisition unit 114 acquires session information of the communication terminal 60. For example, when the data receiving unit 113 receives data of the communication terminal 60, the session information acquisition unit 114 acquires the session information of the communication terminal 60. For example, when the data receiving unit 113 receives uplink data of the communication terminal 60, the session information acquisition unit 114 acquires the session information of the communication terminal 60. The session information acquisition unit 114 may acquire the session information of the communication terminal 60 when the data receiving unit 113 receives downlink data of the communication terminal 60.

[0141] For example, when the PGW 100 does not hold session information of the communication terminal 60, the session information acquisition unit 114 acquires the session information of the communication terminal 60 from the storage unit. For example, when the data receiving unit 113 receives uplink data of the communication terminal 60 for the first time, the session information acquisition unit 114 acquires the session information of the communication terminal 60 from the storage unit. When the data receiving unit 113 receives downlink data of the communication terminal 60 for the first time, the session information acquisition unit 114 may acquire the session information of the communication terminal 60 from the storage unit. On the other hand, when the PGW 100 holds session information of the communication terminal 60, the session information acquisition unit 114 acquires the session information of the communication terminal 60 from the storage unit 106.

[0142] The session information acquisition unit 114 may be an example of a first session information acquisition unit. The session information acquisition unit 114 may be an example of a second session information acquisition unit.

[0143] The data transmission unit 116 transmits data of the communication terminal 60. The data transmission unit 116 transmits the data of the communication terminal 60 based on the session information of the communication terminal 60 acquired by the session information acquisition unit 114, for example.

[0144] The data transmission unit 116 transmits, for example, uplink data of the communication terminal 60. The data transmission unit 116 may transmit downlink data of the communication terminal 60.

[0145] The data transmitting unit 116 uses, for example, a router to transmit the data of the communication terminal 60. If the PGW 100 has a router function, the data transmitting unit 116 may transmit the data of the communication terminal 60 using the router function of the PGW 100.

[0146] When the PGW 100 is separated into the PGW-C 120 and the PGW-U 140, the PGW-C 120 may have a request receiving unit 103, a session information generating unit 104, a storage unit 106, a registration unit 108, a session information synchronizing unit 110, and a response transmitting unit 112, and the PGW-U 140 may have a storage unit 106, a data receiving unit 113, a session information acquiring unit 114, and a data transmitting unit 116. The PGW-C 120 and the PGW-U 140 may share the storage unit 106, or may have the storage unit 106 individually.

[0147] 7 shows an example of a schematic functional configuration of the SGW 300. The SGW 300 includes a receiver 302, a generator 304, a storage unit 306, and a transmitter 312. The receiver 302 includes a route information receiver 303, a request receiver 305, a response receiver 307, and a data receiver 309. The transmitter 312 includes a request transmitter 313 and a data transmitter 315. It is not essential that the SGW 300 includes all of these components.

[0148] The receiving unit 302 receives various types of information. The receiving unit 302 may store the received various types of information in the storage unit 306.

[0149] The receiving unit 302 receives various types of information using, for example, a router. If the SGW 300 has a router function, the receiving unit 302 may receive various types of information using the router function of the SGW 300.

[0150] The route information receiving unit 303 receives route information. The route information receiving unit 303 receives route information from, for example, a router. The route information receiving unit 303 may receive route information from an IPX.

[0151] The generating unit 304 generates a route table. For example, the generating unit 304 generates the route table based on the route information received by the route information receiving unit 303. The generating unit 304 may store the generated route table in the storage unit 306.

[0152] The request receiving unit 305 receives a session creation request from the communication terminal 60 requesting the creation of a session to the PDN 40. The request receiving unit 305 receives the session creation request from the communication terminal 60 from an MME corresponding to the SGW 300, for example.

[0153] The transmitting unit 312 transmits various types of information. The transmitting unit 312 transmits various types of information based on the various types of information stored in the storage unit 306, for example.

[0154] The transmission unit 312 transmits various types of information using, for example, a router. If the SGW 300 has a router function, the transmission unit 312 may transmit various types of information using the router function of the SGW 300.

[0155] The request transmitting unit 313 transmits a session creation request of the communication terminal 60. The request transmitting unit 313 transmits the session creation request of the communication terminal 60 in response to the request receiving unit 305 receiving the session creation request of the communication terminal 60, for example.

[0156] The request sending unit 313 sends the session generation request of the communication terminal 60 to a PGW selected as a transmission target of the session generation request of the communication terminal 60 from among the multiple PGWs included in the system 10 based on, for example, the PGW selection condition. The request sending unit 313 sends the session generation request of the communication terminal 60 to, for example, a PGW having the shortest route to the SGW 300 among the PGWs capable of sending the session generation request of the communication terminal 60. In this case, the PGW selection condition is that the SGW 300 has the shortest route to the SGW 300 among the PGWs capable of sending the session generation request of the communication terminal 60.

[0157] For example, when each PGW of the multiple PGWs included in the system 10 is separated into a PGW-C and a PGW-U, the request transmission unit 313 transmits the session generation request of the communication terminal 60 to a PGW-C selected as a transmission target of the session generation request of the communication terminal 60 from among the multiple PGW-Cs included in the system 10 based on the PGW-C selection condition. The request transmission unit 313 transmits the session generation request of the communication terminal 60 to a PGW-C having the shortest route to the SGW300 among the PGW-Cs capable of transmitting the session generation request of the communication terminal 60. In this case, the PGW-C selection condition is that the PGW-C has the shortest route to the SGW300 among the PGW-Cs capable of transmitting the session generation request of the communication terminal 60.

[0158] The entity that selects the transmission target of the session generation request of the communication terminal 60 is, for example, a router. In this case, the request transmitting unit 313 may transmit the session generation request of the communication terminal 60 to the transmission target of the session generation request of the communication terminal 60 by using the router.

[0159] When SGW 300 has a router function, the entity that selects the transmission target of the session generation request of communication terminal 60 may be SGW 300. In this case, request transmitting unit 313 may select the transmission target of the session generation request of communication terminal 60 according to a best path selection algorithm of BGP based on the route table stored in storage unit 306, and transmit the session generation request of communication terminal 60 to the selected transmission target of the session generation request of communication terminal 60.

[0160] The response receiving unit 307 receives a session creation response of the communication terminal 60 in response to the session creation request of the communication terminal 60 transmitted by the request transmitting unit 313. The response receiving unit 307 receives the session creation response of the communication terminal 60, for example, from a PGW selected as a transmission target of the session creation request of the communication terminal 60. For example, when each PGW of the multiple PGWs included in the system 10 is separated into a PGW-C and a PGW-U, the response receiving unit 307 receives the session creation response of the communication terminal 60 from the PGW-C selected as a transmission target of the session creation request of the communication terminal 60.

[0161] The data receiving unit 309 receives uplink data of the communication terminal 60. The data receiving unit 309 receives the uplink data of the communication terminal 60 from the communication terminal 60, for example.

[0162] The data transmitting unit 315 transmits uplink data of the communication terminal 60. For example, the data transmitting unit 315 transmits the uplink data of the communication terminal 60 received by the data receiving unit 309. For example, the data transmitting unit 315 transmits the uplink data of the communication terminal 60 after the response receiving unit 307 receives a session generation response of the communication terminal 60.

[0163] The data transmission unit 315 transmits the uplink data of the communication terminal 60 to a PGW selected as a transmission target of the uplink data of the communication terminal 60 from among a plurality of PGWs included in the system 10 based on the PGW selection condition, for example. The data transmission unit 315 transmits the uplink data of the communication terminal 60 to a PGW having the shortest route to the SGW 300 among PGWs that can transmit a session generation request of the communication terminal 60, for example.

[0164] For example, when each PGW of the multiple PGWs included in the system 10 is separated into a PGW-C and a PGW-U, the data transmission unit 315 transmits the uplink data of the communication terminal 60 to a PGW-U selected as a transmission target of the uplink data of the communication terminal 60 from among the multiple PGW-Us included in the system 10 based on the PGW-U selection condition. For example, the data transmission unit 315 transmits the uplink data of the communication terminal 60 to a PGW-U having the shortest route to the SGW300 among the PGW-Us capable of transmitting the uplink data of the communication terminal 60. In this case, the PGW-U selection condition is that the PGW-U has the shortest route to the SGW300 among the PGW-Us capable of transmitting a session generation request of the communication terminal 60.

[0165] The PGW selected as the transmission target of the uplink data of the communication terminal 60 is, for example, the same PGW as the PGW selected as the transmission target of the session generation request of the communication terminal 60. The PGW selected as the transmission target of the uplink data of the communication terminal 60 may be a PGW different from the PGW selected as the transmission target of the session generation request of the communication terminal 60. In this case, for example, the PGW selected as the transmission target of the session generation request of the communication terminal 60 is arranged in a network of a first country, and the PGW selected as the transmission target of the uplink data of the communication terminal 60 is arranged in a network of a second country different from the first country. Both the PGW selected as the transmission target of the session generation request of the communication terminal 60 and the PGW selected as the transmission target of the uplink data of the communication terminal 60 may be arranged in the first country.

[0166] The PGW-U selected as the transmission target of the uplink data of the communication terminal 60 is arranged, for example, in a network in which the PGW-C selected as the transmission target of the session generation request of the communication terminal 60 is arranged. The PGW-U selected as the transmission target of the uplink data of the communication terminal 60 may be arranged in a network different from the network in which the PGW-C selected as the transmission target of the session generation request of the communication terminal 60 is arranged. In this case, for example, the PGW-C selected as the transmission target of the session generation request of the communication terminal 60 is arranged in a network of a first country, and the PGW-U selected as the transmission target of the uplink data of the communication terminal 60 is arranged in a network of a second country different from the first country. Both the PGW-C selected as the transmission target of the session generation request of the communication terminal 60 and the PGW-U selected as the transmission target of the uplink data of the communication terminal 60 may be arranged in the first country.

[0167] The entity that selects the transmission target of the uplink data of the communication terminal 60 is, for example, a router. In this case, the data transmitting unit 315 may transmit the uplink data of the communication terminal 60 to the transmission target of the uplink data of the communication terminal 60 using the router.

[0168] When the SGW 300 has a router function, the entity that selects the transmission target of the uplink data of the communication terminal 60 may be the SGW 300. In this case, the data transmitting unit 315 may select the transmission target of the uplink data of the communication terminal 60 according to a best path selection algorithm of BGP based on the route table stored in the storage unit 306, and transmit the uplink data of the communication terminal 60 to the selected transmission target of the uplink data of the communication terminal 60.

[0169] When the SGW300 is separated into the SGW-C320 and the SGW-U340, the SGW-C320 may have a route information receiving unit 303, a generating unit 304, a request receiving unit 305, a storing unit 306, a response receiving unit 307, and a request transmitting unit 313, and the SGW-U340 may have a storing unit 306, a data receiving unit 309, and a data transmitting unit 315. The SGW-C320 and the SGW-U340 may share the storing unit 306, or may have the storing unit 306 individually.

[0170] Fig. 8 is a schematic diagram of another example of the system 10. Fig. 8 illustrates an example in which the mobile communication service provided by the system 10 is a 5G communication service. Here, differences from the system 10 in Fig. 1 will be mainly described.

[0171] The system 10 may include multiple H-SMFs. Fig. 8 illustrates an example in which the system 10 includes two H-SMFs, H-SMF 420 and H-SMF 520. The number of H-SMFs included in the system 10 is not limited to two, and may be three or more.

[0172] The system 10 may include a plurality of H-UPFs. Fig. 8 illustrates an example in which the system 10 includes two H-UPFs, H-UPF 440 and H-UPF 540. The number of H-UPFs included in the system 10 is not limited to two, and may be three or more.

[0173] The system 10 may include a V-SMF 620. The system 10 may include a V-UPF 640. The V-UPF 640 may be disposed in a network in which the V-SMF 620 is disposed.

[0174] The system 10 may include a router 23. The system 10 may include a database 33. The system 10 may include a router 25. The system 10 may include a database 35. The system 10 may include a router 27.

[0175] The multiple H-SMFs and multiple H-UPFs included in the system 10 may be arranged in an HPLMN, which is a network of a telecommunications carrier that has issued a SIM card to the user of the communication terminal 60. The V-SMF 620 and V-UPF 640 included in the system 10 may be arranged in a VPLMN, which is a network of a telecommunications carrier in a location visited by the user of the communication terminal 60. Here, the explanation will be continued assuming that the subscriber information of the user of the communication terminal 60 is synchronized in advance between the HPLMNs.

[0176] Each of the multiple H-SMFs is located in a network with a different ASN, and each H-SMF is assigned the same IP address. For example, IP Anycast is used to assign the same IP address to each H-SMF. Here, the configurations of the H-SMF420 and H-SMF520 shown in FIG. 8 will be described.

[0177] The H-SMF 420 has a function of managing sessions. The H-SMF 420 is disposed, for example, in a network of a first country. In the example shown in Fig. 8, the H-SMF 420 is disposed in a network in Tokyo, Japan, whose ASN is 65001.

[0178] An IP address may be assigned to the H-SMF 420. In the example of the system 10 shown in Fig. 8, the H-SMF 420 is assigned an IP address AAAA in the subnet mask 32.

[0179] The H-SMF 520 has a function for managing sessions. The H-SMF 520 may have the same function as the H-SMF 420.

[0180] For example, the H-SMF 520 is located in a network having an ASN different from the ASN of the network in which the H-SMF 420 is located. For example, the H-SMF 520 is located in a network in a second country different from the first country. The H-SMF 520 may be located in the network in the first country. In the example shown in FIG. 8, the H-SMF 520 is located in a network in Singapore having an ASN of 65002.

[0181] An IP address may be assigned to the H-SMF 520. In the example of the system 10 shown in FIG 8, the H-SMF 520 is assigned an IP address AAAA in the subnet mask 32.

[0182] Each of the multiple H-UPFs is located in a network with a different ASN, and each H-UPF is assigned the same IP address. For example, IP Anycast is used to assign the same IP address to each H-UPF. Here, the configuration of each of the H-UPF440 and H-UPF540 shown in FIG. 8 will be described.

[0183] The H-UPF 440 has a function of transferring data of the communication terminal 60. The H-UPF 440 is disposed, for example, in a network in which the H-SMF 420 is disposed. The H-UPF 440 is disposed, for example, in a network in a first country. In the example shown in Fig. 8, the H-UPF 440 is disposed in a network in Tokyo, Japan, whose ASN is 65001.

[0184] The H-UPF 440 may be assigned an IP address. For example, the H-UPF 440 is assigned an IP address that is different from the IP address assigned to the H-SMF 420. In the example of the system 10 shown in FIG. 8, the H-UPF 440 is assigned BBBB of the subnet mask 32.

[0185] The H-UPF 540 has a function of transferring data of the communication terminal 60. The H-UPF 540 may have the same function as the H-UPF 440.

[0186] The H-UPF 540 is disposed, for example, in a network in which the H-SMF 520 is disposed. The H-UPF 540 is disposed, for example, in a network of an ASN different from the ASN of the network in which the H-UPF 440 is disposed. The H-UPF 540 is disposed, for example, in a network of a second country different from the first country. The H-UPF 540 may be disposed in the network of the first country. In an example shown in FIG. 8, the H-UPF 540 is disposed in a network of Singapore with an ASN of 65002.

[0187] The H-UPF 540 may be assigned an IP address. For example, the H-UPF 540 is assigned an IP address that is different from the IP address assigned to the H-SMF 520. In the example of the system 10 shown in FIG. 8, the H-UPF 540 is assigned BBBB of the subnet mask 32.

[0188] The V-SMF 620 has a function of managing sessions. In the example shown in FIG. 8, the V-SMF 620 is disposed in a network of a carrier A in Singapore, whose ASN is 65003.

[0189] An IP address may be assigned to the V-SMF 620. In the example of the system 10 shown in Figure 8, the V-SMF 620 is assigned an IP address CCCC in the subnet mask 32.

[0190] V-UPF 640 has a function of transferring data of communication terminal 60. V-UPF 640 is arranged, for example, in a network in which V-SMF 620 is arranged. In the example shown in Fig. 8, V-UPF 640 is arranged in a network of a Singaporean communication carrier A whose ASN is 65003.

[0191] An IP address may be assigned to the V-UPF 640. For example, the V-UPF 640 is assigned an IP address that is different from the IP address assigned to the V-SMF 620. In the example of the system 10 shown in FIG. 8, the V-UPF 640 is assigned DDDD in the subnet mask 32.

[0192] The router 23 has a function of relaying data. The router 23 relays, for example, uplink data. The router 23 relays, for example, downlink data.

[0193] The router 23 is disposed, for example, in the HPLMN in which the H-SMF 420 is disposed. The router 23 is disposed, for example, in the HPLMN in which the H-UPF 440 is disposed.

[0194] The router 23 may be separate from the H-SMF 420 and the H-UPF 440. The router 23 may be integrated with the H-SMF 420. The router 23 may be integrated with the H-UPF 440.

[0195] The router 25 has a function of relaying data. The router 25 has the same function as the router 23.

[0196] The router 25 is disposed, for example, in the HPLMN in which the H-SMF 520 is disposed. The router 25 is disposed, for example, in the HPLMN in which the H-UPF 540 is disposed.

[0197] The router 25 may be separate from the H-SMF 520 and the H-UPF 540. The router 25 may be integrated with the H-SMF 520. The router 25 may be integrated with the H-UPF 540.

[0198] The router 27 has a function of relaying data. The router 27 relays, for example, uplink data. The router 27 relays, for example, downlink data.

[0199] The router 27 is disposed, for example, in a VPLMN in which the V-SMF 620 is disposed. The router 27 is disposed, for example, in a VPLMN in which the V-UPF 640 is disposed.

[0200] The router 27 may be separate from the V-SMF 620 and the V-UPF 640. The router 27 may be integrated with the V-SMF 620. The router 27 may be integrated with the V-UPF 640.

[0201] For example, route information between organizations is exchanged among the router 23, the router 25, and the router 27 in accordance with BGP. For example, in response to a change in the route information, the route information is exchanged among the router 23, the router 25, and the router 27. The route information may also be exchanged periodically among the router 23, the router 25, and the router 27.

[0202] The router 23 advertises the route information, for example, to the router 27. The router 23 may advertise the route information to IPX. The router 25 may advertise the route information in the same manner as the router 23.

[0203] In the example of the system 10 shown in Fig. 8, the router 23 advertises ASN=65001, the IP address of the H-SMF 420=AAAA / 32, and the IP address of the H-UPF 440=BBBB / 32. Also, in the example of the system 10 shown in Fig. 8, the router 25 advertises ASN=65002, the IP address of the H-SMF 520=AAAA / 32, and the IP address of the H-UPF 540=BBBB / 32.

[0204] The router 27 advertises the route information, for example, to the routers 23 and 25. The router 27 may advertise the route information to IPX. In the example of the system 10 shown in Fig. 8, the router 27 advertises ASN=65003, the IP address of the V-SMF 620=CCCC / 32, and the IP address of the V-UPF 640=DDDD / 32.

[0205] The router 27 generates, for example, a route table. The router 27 generates the route table based on, for example, the route information advertised by each of the router 23 and the router 25. The router 27 generates the route table by, for example, associating the ASN of the network in which the router is located with the IP address assigned to the device located in the network. In an example of the system 10 shown in Fig. 8, the router 27 generates a route table including ASN=65001 and IP address=AAAA / 32 of the H-SMF 420, ASN=65001 and IP address=BBBB / 32 of the H-UPF 440, ASN=65002 and IP address=AAAA / 32 of the H-SMF 520, and ASN=65002 and IP address=BBBB / 32 of the H-UPF 540.

[0206] The V-SMF 620 receives, for example, a session creation request for requesting the creation of a session to the PDN 40 from the communication terminal 60 of a user visiting the VPLMN. The session creation request includes, for example, the IP address of the V-SMF 620. The session creation request includes, for example, the IP address of the V-UPF 640. The session creation request includes, for example, a TEID assigned to the communication tunnel of the V-SMF 620. The session creation request includes, for example, a TEID assigned to the communication tunnel of the V-UPF 640 and different from the TEID assigned to the communication tunnel of the V-SMF 620. The session creation request includes, for example, the IP address of the H-SMF included in the system 10. The session creation request includes, for example, the IP address of the H-UPF included in the system 10.

[0207] The V-SMF 620 may transmit the received session creation request of the communication terminal 60 using the router 27. The router 27 may select an H-SMF to which the session creation request of the communication terminal 60 is to be transmitted from among a plurality of H-SMFs included in the system 10, based on predetermined H-SMF selection conditions.

[0208] For example, the router 27 selects an H-SMF having the shortest route to the V-SMF 620 from among the multiple H-SMFs included in the system 10 as an H-SMF to which a session creation request from the communication terminal 60 is to be transmitted. For example, when there are multiple H-SMFs to which the same IP address is assigned, the router 27 selects an H-SMF having the shortest route to the SGW 300 from among the multiple H-SMFs to which the same IP address is assigned as an H-SMF to which a session creation request from the communication terminal 60 is to be transmitted, based on the generated route table and in accordance with the best path selection algorithm of BGP.

[0209] In the example of the system 10 shown in Fig. 8, the route from the H-SMF420 to the V-SMF620 passes through the network 13 constructed in Tokyo and the network 15 constructed in Singapore. In contrast, the route from the H-SMF520 to the V-SMF620 passes only through the network 15. Therefore, in the example of the system 10 shown in Fig. 8, when the V-SMF620 is in a state in which it can transmit a session creation request of the communication terminal 60 to both the H-SMF420 and the H-SMF520 using the router 27, the distance of the route from the H-SMF520 to the V-SMF620 is shorter than the distance of the route from the H-SMF420 to the V-SMF620, so that the router 27 selects the H-SMF520 from the H-SMF420 and the H-SMF520 as the H-SMF to which the session creation request of the communication terminal 60 is to be transmitted. Here, the explanation will be continued on the assumption that the router 27 has selected the H-SMF 520 as the H-SMF to which the session creation request of the communication terminal 60 is to be transmitted.

[0210] The V-SMF 620 may transmit the session creation request of the communication terminal 60 to the H-SMF 520 via the network 15 using the router 27. The H-SMF 520 may receive the session creation request of the communication terminal 60 via the network 15 using the router 25. The H-SMF 520 may be an example of an H-SMF selected as a destination for sending the session creation request of the communication terminal 60.

[0211] The H-SMF 520 may generate session information of the communication terminal 60 in response to receiving a session generation request for the communication terminal 60 from the V-SMF 620. The session information includes, for example, an IP address of the H-SMF included in the system 10. The session information includes, for example, an IP address of the H-UPF included in the system 10, which is different from the IP address of the H-SMF. The session information includes, for example, a TEID assigned to a communication tunnel of each H-SMF of the multiple H-SMFs included in the system 10. The session information includes, for example, a TEID assigned to a communication tunnel of each H-UPF of the multiple H-UPFs included in the system 10 and different from the TEID assigned to the communication tunnel of the H-SMF. The session information includes, for example, an IP address of the V-SMF 620. The session information includes, for example, an IP address of the V-UPF 640, which is different from the IP address of the V-SMF 620. The session information includes, for example, a TEID assigned to a communication tunnel of the V-SMF 620. The session information includes, for example, a TEID that is assigned to a communication tunnel of V-UPF640 and is different from a TEID that is assigned to a communication tunnel of V-SMF620.

[0212] The H-SMF 520 may register the generated session information of the communication terminal 60 in the database 35 corresponding to the H-SMF 520. The H-SMF 520 may store, for example, the IP address of the database 35 in advance.

[0213] The database 35 includes, for example, a message queue that temporarily stores session information of the communication terminal 60. The database 35 may be an example of a storage unit.

[0214] The database 35 may be separate from the H-SMF 520. The database 35 may be integrated with the H-SMF 520.

[0215] The database 35 is disposed, for example, in a network in which the H-SMF 520 is disposed. The database 35 may be disposed in a network of an ASN different from the ASN of the network in which the H-SMF 520 is disposed.

[0216] The database 35 may synchronize the session information of the registered communication terminal 60 between the database 35 and the database 33 corresponding to the H-SMF 420. The database 33 may be an example of a storage unit.

[0217] The database 35 uses, for example, a Pub / Sub (Publish / Subscribe) method to synchronize the session information of the communication terminal 60 between the database 35 and the database 33. In this case, the database 35 may be a publisher, and the database 33 may be a subscriber.

[0218] For example, the database 35 sends a message including session information of the communication terminal 60 to a topic. The database 33 obtains the session information of the communication terminal 60 by receiving a message from a subscription corresponding to the topic to which the message was sent by the database 35. In this way, the session information of the communication terminal 60 is synchronized between the database 35 and the database 33.

[0219] The database 33 may be separate from the H-SMF 420. The database 33 may be integrated with the H-SMF 420.

[0220] The database 33 is disposed, for example, in a network in which the H-SMF 420 is disposed. The database 33 may be disposed in a network of an ASN different from the ASN of the network in which the H-SMF 420 is disposed.

[0221] In response to generating the session information of the communication terminal 60, the H-SMF 520 may use the router 25 to transmit a session generation response of the communication terminal 60 to the V-SMF 620 via the network 15 in response to the session generation request of the communication terminal 60. The session generation response includes, for example, an IP address of the H-SMF included in the system 10. The session generation response includes, for example, an IP address of the H-UPF included in the system 10. The session generation response includes, for example, a TEID assigned to a communication tunnel of each H-SMF of the multiple H-SMFs included in the system 10. The session generation response includes, for example, a TEID assigned to a communication tunnel of each H-UPF of the multiple H-UPFs included in the system 10.

[0222] The V-SMF 620 may receive the session creation response of the communication terminal 60 via the network 15 using the router 27. This allows the V-SMF 620 to create a session for the communication terminal 60 to the PDN 40 based on the session creation response of the communication terminal 60.

[0223] Thereafter, the V-UPF 640 may receive the uplink data of the communication terminal 60 from the communication terminal 60. The V-UPF 640 may transmit the received uplink data of the communication terminal 60 using the router 27.

[0224] The router 27 selects an H-UPF to which the communication terminal 60 is to transmit uplink data from among the multiple H-UPFs included in the system 10, based on, for example, predetermined H-UPF selection conditions. When there are multiple H-UPFs to which the same IP address is assigned, for example, the router 27 selects an H-UPF having the shortest route to the V-UPF 640 from among the multiple H-UPFs to which the same IP address is assigned, as an H-UPF to which the communication terminal 60 is to transmit uplink data, based on the generated route table and in accordance with the best path selection algorithm of BGP.

[0225] 8, when the V-UPF 640 is in a state in which it can transmit uplink data of the communication terminal 60 to both the H-UPF 440 and the H-UPF 540 using the router 27, the router 27 selects the H-UPF 540 from the H-UPF 440 and the H-UPF 540 as the H-UPF to which the uplink data of the communication terminal 60 is to be transmitted. Here, the explanation will be continued assuming that the router 27 selects the H-UPF 540 as the H-UPF to which the uplink data of the communication terminal 60 is to be transmitted.

[0226] The V-UPF 640 may transmit uplink data of the communication terminal 60 to the H-UPF 540 via the network 15 using the router 27. The H-UPF 540 may receive uplink data of the communication terminal 60 via the network 15 using the router 25. The H-UPF 540 may be an example of an H-UPF selected as a transmission target of the uplink data of the communication terminal 60.

[0227] When H-UPF 540 receives uplink data of communication terminal 60 and does not hold session information of communication terminal 60, it acquires the session information of communication terminal 60 from database 35 and processes the data of communication terminal 60 based on the session information of communication terminal 60 acquired from database 35. On the other hand, when H-UPF 540 receives uplink data of communication terminal 60 and holds session information of communication terminal 60, it processes the data of communication terminal 60 based on the session information of communication terminal 60 that it holds.

[0228] The database 35 may be a database corresponding to the H-UPF 540. The database 35 may be separate from the H-UPF 540, or may be integrated with the H-UPF 540. The database 35 may be disposed, for example, in a network in which the H-UPF 540 is disposed, or may be disposed in a network of an ASN different from the ASN of the network in which the H-UPF 540 is disposed.

[0229] For example, when the state of at least one of the multiple H-UPFs included in the system 10 changes, such as when a failure occurs in one of the multiple H-UPFs included in the system 10 or when maintenance is started on the H-UPF, the router 27 updates the route table. Based on the updated route table, the router 27 may select an H-UPF to which the communication terminal 60 transmits uplink data from among the multiple H-UPFs included in the system 10, in accordance with the best path selection algorithm of BGP.

[0230] 8, in the case where the V-UPF 640 is transmitting uplink data of the communication terminal 60 to the H-UPF 540 using the router 27, if the state where the V-UPF 640 can transmit the uplink data of the communication terminal 60 to both the H-UPF 440 and the H-UPF 540 using the router 27 changes to the state where the V-UPF 640 can transmit the uplink data of the communication terminal 60 only to the H-UPF 440 using the router 27, the router 27 may update the route table. After that, the router 27 may select the H-UPF 440 as the H-UPF to which the uplink data of the communication terminal 60 is to be transmitted based on the updated route table.

[0231] The V-UPF 640 may transmit uplink data of the communication terminal 60 to the H-UPF 440 via the networks 15 and 13 using the router 27. The H-UPF 440 may receive uplink data of the communication terminal 60 via the networks 15 and 13 using the router 23. The H-UPF 440 may be an example of an H-UPF selected as a transmission target of the uplink data of the communication terminal 60.

[0232] When H-UPF 440 receives uplink data of communication terminal 60 and does not hold session information, it acquires, from database 33, session information of communication terminal 60 synchronized between database 33 and database 35, and processes the data of communication terminal 60 based on the session information of communication terminal 60 acquired from database 33. On the other hand, when H-UPF 440 receives uplink data of communication terminal 60 and holds session information of communication terminal 60, it processes the data of communication terminal 60 based on the session information of communication terminal 60 that it holds.

[0233] The database 33 may be a database corresponding to the H-UPF 440. The database 33 may be separate from the H-UPF 440, or may be integrated with the H-UPF 440. The database 33 may be disposed, for example, in a network in which the H-UPF 440 is disposed, or may be disposed in a network of an ASN different from the ASN of the network in which the H-UPF 440 is disposed.

[0234] In the example of the system 10 shown in Fig. 8, when data of the communication terminal 60 is communicated on a path between the communication terminal 60 and the PDN 40 via the V-UPF 640 and the H-UPF 540, the data of the communication terminal 60 is communicated by domestic roaming. On the other hand, in the example of the system 10 shown in Fig. 8, when data of the communication terminal 60 is communicated on a path between the communication terminal 60 and the PDN 40 via the V-UPF 640 and the H-UPF 440, the data of the communication terminal 60 is communicated by international roaming.

[0235] In the example of the system 10 shown in Fig. 8, when the V-SMF 620 is in a state in which it can transmit the session generation request of the communication terminal 60 only to the H-SMF 420 using the router 27 at the timing when the V-SMF 620 transmits the session generation request of the communication terminal 60, the router 27 selects the H-UPF 440 as the H-SMF to which the session generation request of the communication terminal 60 is to be transmitted. In this case, the V-SMF 620 may transmit the session generation request of the communication terminal 60 to the H-UPF 440 via the network 15 and the network 13 using the router 27. The H-UPF 440 may receive the session generation request of the communication terminal 60 via the network 15 and the network 13 using the router 23. The H-SMF 420 may be an example of the H-SMF selected as the transmission target of the session generation request of the communication terminal 60.

[0236] In response to receiving a session generation request from the V-SMF 620, the H-SMF 420 may generate session information of the communication terminal 60. The H-SMF 420 may register the generated session information of the communication terminal 60 in the database 33. The H-SMF 420 may store, for example, an IP address of the database 33 in advance.

[0237] The database 33 may have the same function as the database 35. For example, when the H-SMF 420 registers the session information of the communication terminal 60 in the database 33, the database 33 synchronizes the session information of the communication terminal 60 between the database 33 and the database 35 in the same manner as the database 35.

[0238] 8, a communications carrier that has issued a SIM card to a user of the communications terminal 60 may establish an HPLMN at three or more bases. In this case, the same IP address may be assigned to the H-SMF at each of the three or more bases, and the same IP address may be assigned to the H-UPF at each of the three or more bases.

[0239] According to the system 10 shown in FIG. 8, the V-SMF 620 can preferentially transmit the session generation request of the communication terminal 60 to the H-SMF that is closer to the V-SMF 620, and the V-UPF 640 can preferentially transmit the uplink data of the communication terminal 60 to the H-UPF that is closer to the V-UPF 640. Therefore, the system 10 shown in FIG. 8 contributes to the realization of a 5G communication service in which the occurrence of communication delays of the communication terminal 60 is suppressed. Furthermore, by adopting a configuration in which the H-UPF that receives the uplink data of the communication terminal 60 from the V-UPF 640 does not hold the session information of the communication terminal 60 as a trigger, the H-UPF that does not process the data of the communication terminal 60 does not need to obtain the session information of the communication terminal 60. As a result, the system 10 shown in FIG. 8 contributes to the realization of a 5G communication service in which the consumption of communication resources is suppressed.

[0240] 9 is an explanatory diagram for explaining another example of the flow of processing in the system 10. Here, the description will be given assuming that a state in which the user of the communication terminal 60 has visited the VPLMN is a starting state.

[0241] In S302, the V-SMF620 transmits a session creation request of the communication terminal 60 requesting the creation of a session to the PDN 40. The V-SMF620 transmits the session creation request of the communication terminal 60 received from, for example, an AMF (Access and Mobility Management Function) corresponding to the V-SMF620 that has accepted an attach request from the communication terminal 60 and performed authentication processing of the communication terminal 60. Here, the explanation will be continued assuming that the V-SMF620 is in a state in which it can transmit the session creation request of the communication terminal 60 to both the H-SMF420 and the H-SMF520 using the router 27, the router 27 selects the H-SMF520 as the H-SMF to which the session creation request of the communication terminal 60 is to be transmitted based on the H-SMF selection condition, and the V-SMF620 transmits the session creation request of the communication terminal 60 to the H-SMF520 using the router 27.

[0242] The H-SMF 520 receives a session creation request for the communication terminal 60 from the V-SMF 620. The H-SMF 520 may create session information for the communication terminal 60 based on the received session creation request from the communication terminal 60.

[0243] In S304, the H-SMF 520 registers the generated session information of the communication terminal 60 in the database 35. In S306, the database 35 synchronizes the session information of the communication terminal 60 registered by the H-SMF 520 in S304 between the database 35 and the database 33.

[0244] In S308, H-SMF 520 transmits a create session response of communication terminal 60 to the create session request of communication terminal 60 to V-SMF 620. V-SMF 620 receives the create session response of communication terminal 60 from H-SMF 520. V-SMF 620 may store the received create session response of communication terminal 60 so that V-SMF 620 and V-UPF 640 can use the create session response of communication terminal 60.

[0245] In S310, the V-UPF 640 transmits uplink data of the communication terminal 60 based on the session creation response of the communication terminal 60 received by the V-SMF 620 in S308. Here, the explanation will be continued assuming that the V-UPF 640 is in a state in which it can transmit the uplink data of the communication terminal 60 to both the H-UPF 440 and the H-UPF 540 using the router 27, the router 27 selects the H-UPF 540 as the H-UPF to which the uplink data of the communication terminal 60 is to be transmitted based on the H-UPF selection condition, the V-UPF 640 transmits the uplink data of the communication terminal 60 to the H-UPF 540 using the router 27, and the H-UPF 540 does not hold session information of the communication terminal 60.

[0246] In S312, since the H-UPF 540 does not hold session information of the communication terminal 60 for processing the uplink data of the communication terminal 60 received in S310, the H-UPF 540 acquires the session information of the communication terminal 60 from the database 35. The H-UPF 540 processes the data of the communication terminal 60 based on the session information of the communication terminal 60 acquired from the database 35.

[0247] In S314, the maintenance work is started on the H-UPF 540. In response to the start of the maintenance work on the H-UPF 540, the router 27 may update the route table.

[0248] In S316, V-UPF 640 transmits uplink data of communication terminal 60 based on the session creation response of communication terminal 60 received by V-SMF 620 in S308. Here, the explanation will be continued assuming that V-UPF 640 is in a state in which it can transmit uplink data of communication terminal 60 only to H-UPF 440 using router 27, that V-UPF 640 transmits the uplink data of communication terminal 60 to H-UPF 440 using router 27, and that H-UPF 440 does not hold session information of communication terminal 60.

[0249] In S318, since the H-UPF 440 does not hold session information of the communication terminal 60 for processing the uplink data of the communication terminal 60 received in S316, the H-UPF 440 acquires, from the database 33, the session information of the communication terminal 60 that was synchronized between the database 33 and the database 35 in S306. The H-UPF 440 processes the data of the communication terminal 60 based on the session information of the communication terminal 60 acquired from the database 33.

[0250] Fig. 10 shows a schematic diagram of another example of the system 10. Here, differences from the system 10 shown in Fig. 8 will be mainly described.

[0251] The H-SMF 420 may be located on a cloud. The H-SMF 420 may be located on the same network as the PDN 40, or may be located on a different network from the PDN 40. In the example of the system 10 shown in FIG. 10, the H-SMF 420 is located in region 1 on a cloud with an ASN of 65001.

[0252] The H-SMF 520 may be located on a cloud. The H-SMF 520 may be located on the same network as the PDN 40, or may be located on a different network from the PDN 40. In the example of the system 10 shown in FIG. 10, the H-SMF 520 is located in region 2 on a cloud with an ASN of 65002.

[0253] Each of the multiple H-SMFs included in the system 10 may be able to access the database 48. Each H-SMF accesses the database 48, for example, via the PDN 40. Each H-SMF may directly access the database 48. An H-SMF selected as a transmission target of a session generation request from the communication terminal 60 may register the generated session information of the communication terminal 60 in the database 48.

[0254] Each of the multiple H-UPFs included in the system 10 may be able to access the database 48. Each H-UPF accesses the database 48, for example, via the PDN 40. Each H-UPF may directly access the database 48. If the H-UPF selected as the transmission target of the uplink data of the communication terminal 60 does not hold session information of the communication terminal 60, the H-UPF may acquire the session information of the communication terminal 60 from the database 48 and process the data of the communication terminal 60 based on the session information of the communication terminal 60 acquired from the database 48.

[0255] The resource management device 700 manages the physical resources on the cloud, for example, by allocating the physical resources on the cloud to each H-SMF of the multiple H-SMFs included in the system 10. The resource management device 700 determines the amount of the physical resources on the cloud to be allocated to each H-SMF, for example, based on the load status of each H-SMF.

[0256] Resource management apparatus 700 determines the amount of physical resources on the cloud to be allocated to each H-SMF, for example, so that a larger amount of resources is allocated to an H-SMF that receives a larger number of session creation requests per unit time. Resource management apparatus 700 determines the amount of physical resources on the cloud to be allocated to each H-SMF, for example, so that a larger amount of resources is allocated to an H-SMF that has a larger amount of traffic per unit time. Resource management apparatus 700 may determine the amount of physical resources on the cloud to be allocated to each H-SMF, for example, so that a larger amount of resources is allocated to an H-SMF that has a slower processing speed.

[0257] The resource management device 700 transmits, for example, resource amount information indicating the amount of physical resources on the cloud to be allocated to each H-SMF to each H-SMF. The resource management device 700 transmits the resource amount information to each H-SMF via, for example, the PDN 40.

[0258] Each H-SMF may receive resource amount information from the resource management device 700. Each H-SMF may use physical resources on the cloud allocated by the resource management device 700 to execute processing related to mobile communication services.

[0259] The resource management device 700 changes the resource amount of the physical resources on the cloud to be allocated to each H-SMF based on, for example, the usage status of the physical resources on the cloud. The resource management device 700 changes the resource amount of the physical resources on the cloud to be allocated to each H-SMF based on, for example, the usage rate of the CPU on the cloud. The resource management device 700 changes the resource amount of the physical resources on the cloud to be allocated to each H-SMF, for example, when the usage rate of the CPU on the cloud exceeds a predetermined CPU usage rate threshold. The resource management device 700 may change the resource amount of the physical resources on the cloud to be allocated to each H-SMF, when the usage rate of the CPU on the cloud falls below a predetermined CPU usage rate threshold. The resource management device 700 may change the resource amount of the physical resources on the cloud to be allocated to each H-SMF based on the usage rate of the memory on the cloud. The resource management device 700 changes the resource amount of the physical resources on the cloud to be allocated to each H-SMF, for example, when the usage rate of the memory on the cloud exceeds a predetermined memory usage rate threshold. The resource management device 700 may change the amount of physical resources on the cloud allocated to each H-SMF when the usage rate of the memory on the cloud falls below a predetermined memory usage rate threshold. The resource management device 700 may periodically change the amount of physical resources on the cloud allocated to each H-SMF.

[0260] According to the system 10 shown in FIG. 10, the session information of the communication terminal 60 is registered in the database 48 arranged on the cloud, and the H-UPF selected as the transmission target of the uplink data of the communication terminal 60 acquires the session information of the communication terminal 60 from the database 48 when the H-UPF selected as the transmission target of the uplink data of the communication terminal 60 does not hold the session information of the communication terminal 60. Then, the H-UPF selected as the transmission target of the uplink data of the communication terminal 60 processes the data of the communication terminal 60 based on the session information of the communication terminal 60 acquired from the database 48. By registering the session information of the communication terminal 60 in the database 48 arranged on the cloud, it is not necessary to transmit and receive the session information of the communication terminal 60 between the bases of the HPLMN in order to synchronize the session information of the communication terminal 60 between the databases arranged at each base of the HPLMN. As a result, the system 10 shown in FIG. 10 contributes to the realization of a 5G communication service in which the consumption of communication resources is further suppressed and the risk of information leakage is further reduced.

[0261] Fig. 11 shows a schematic diagram of another example of the system 10. Here, differences from the system 10 shown in Fig. 10 will be mainly described.

[0262] The H-UPF 440 may be located on a cloud. The H-UPF 440 may be located on the same network as the PDN 40, or may be located on a network different from the PDN 40. In an example of the system 10 shown in FIG. 11, the H-UPF 440 is located in region 1 on a cloud with an ASN of 65001.

[0263] The H-UPF 540 may be located on a cloud. The H-UPF 540 may be located on the same network as the PDN 40, or may be located on a different network from the PDN 40. In an example of the system 10 shown in FIG. 11, the H-UPF 540 is located in region 2 on a cloud with an ASN of 65002.

[0264] The system 10 may further include a router 83. For example, when the H-SMF 420 is selected as a transmission target of the session generation request of the communication terminal 60, the H-SMF 420 receives the session generation request of the communication terminal 60 via the network 15, the network 13, and the router 23 using the router 83. For example, when the H-UPF 440 is selected as a transmission target of the uplink data of the communication terminal 60, the H-UPF 440 receives the uplink data of the communication terminal 60 via the network 15, the network 13, and the router 23 using the router 83.

[0265] The system 10 may further include a router 85. For example, when the H-SMF 520 is selected as a transmission target of the session generation request of the communication terminal 60, the H-SMF 520 receives the session generation request of the communication terminal 60 via the network 15 and the router 25 using the router 85. For example, when the H-UPF 540 is selected as a transmission target of the uplink data of the communication terminal 60, the H-UPF 540 receives the uplink data of the communication terminal 60 via the network 15 and the router 25 using the router 85.

[0266] The resource management device 700 manages the physical resources on the cloud, for example, by allocating the physical resources on the cloud to each H-UPF of the multiple H-UPFs included in the system 10. The resource management device 700 determines the amount of the physical resources on the cloud to be allocated to each H-UPF, for example, based on the load status of each H-UPF.

[0267] The resource management device 700 determines the amount of physical resources on the cloud to be allocated to each H-UPF, for example, so as to allocate a larger amount of resources to an H-UPF that receives more uplink data per unit time. The resource management device 700 determines the amount of physical resources on the cloud to be allocated to each H-UPF, for example, so as to allocate a larger amount of resources to an H-UPF that has a larger amount of traffic per unit time. The resource management device 700 determines the amount of physical resources on the cloud to be allocated to each H-UPF, for example, so as to allocate a larger amount of resources to an H-UPF that has a larger number of sessions. The resource management device 700 may determine the amount of physical resources on the cloud to be allocated to each H-UPF, for example, so as to allocate a larger amount of resources to an H-UPF that has a slower processing speed.

[0268] The resource management device 700 transmits, for example, resource amount information indicating the amount of physical resources on the cloud to be allocated to each H-UPF to each H-UPF. The resource management device 700 transmits the resource amount information to each H-UPF via, for example, the PDN 40.

[0269] Each H-UPF may receive resource amount information from resource management device 700. Each H-UPF may use physical resources on the cloud allocated by resource management device 700 to execute processing related to mobile communication services.

[0270] The resource management device 700 changes the resource amount of the physical resources on the cloud to be allocated to each H-UPF based on, for example, the usage status of the physical resources on the cloud. The resource management device 700 changes the resource amount of the physical resources on the cloud to be allocated to each H-UPF based on the usage status of the physical resources on the cloud in the same manner as in the case of changing the resource amount of the physical resources on the cloud to be allocated to each H-SMF based on, for example, the usage status of the physical resources on the cloud. The resource management device 700 may periodically change the resource amount of the physical resources on the cloud to be allocated to each H-UPF.

[0271] 12 is an explanatory diagram for explaining another example of the flow of processing in the system 10. Here, the description will be given assuming that a state in which the user of the communication terminal 60 has visited a VPLMN is a starting state.

[0272] In S402, V-SMF620 transmits a session creation request of communication terminal 60 requesting the creation of a session to PDN 40. Here, the explanation will be continued assuming that V-SMF620 is in a state in which it can transmit the session creation request of communication terminal 60 to both H-SMF420 and H-SMF520 using router 27, that router 27 selects H-SMF520 as the H-SMF to which the session creation request of communication terminal 60 is to be transmitted based on the H-SMF selection condition, and that V-SMF620 transmits the session creation request of communication terminal 60 to H-SMF520 using router 27.

[0273] The H-SMF 520 receives a session creation request for the communication terminal 60 from the V-SMF 620. The H-SMF 520 may create session information for the communication terminal 60 based on the received session creation request from the communication terminal 60.

[0274] In S404, H-SMF 520 registers the generated session information of communication terminal 60 in database 48 located on the cloud. In S406, H-SMF 520 transmits a session creation response of communication terminal 60 to the session creation request of communication terminal 60 to V-SMF 620. V-SMF 620 receives the session creation response of communication terminal 60 from H-SMF 520.

[0275] In S408, the V-UPF 640 transmits the uplink data of the communication terminal 60 based on the session creation response of the communication terminal 60 received by the V-SMF 620 in S406. Here, the explanation will be continued assuming that the V-UPF 640 is in a state in which it can transmit the uplink data of the communication terminal 60 to both the H-UPF 440 and the H-UPF 540 using the router 27, the router 27 selects the H-UPF 540 as the H-UPF to which the uplink data of the communication terminal 60 is to be transmitted based on the H-UPF selection condition, the V-UPF 640 transmits the uplink data of the communication terminal 60 to the H-UPF 540 using the router 27, and the H-UPF 540 does not hold session information of the communication terminal 60.

[0276] In S410, since the H-UPF 540 does not hold session information of the communication terminal 60 for processing the uplink data of the communication terminal 60 received in S408, the H-UPF 540 acquires the session information of the communication terminal 60 from the database 48 located on the cloud. The H-UPF 540 processes the data of the communication terminal 60 based on the session information of the communication terminal 60 acquired from the database 48.

[0277] In S412, the maintenance work is started on the H-UPF 540. In response to the start of the maintenance work on the H-UPF 540, the router 27 may update the route table.

[0278] In S414, V-UPF 640 transmits uplink data of communication terminal 60 based on the session creation response of communication terminal 60 received by V-SMF 620 in S406. Here, the explanation will be continued assuming that V-UPF 640 is in a state in which it can transmit uplink data of communication terminal 60 only to H-UPF 440 using router 27, that V-UPF 640 transmits the uplink data of communication terminal 60 to H-UPF 440 using router 27, and that H-UPF 440 does not hold session information of communication terminal 60.

[0279] In S416, since the H-UPF 440 does not hold session information of the communication terminal 60 for processing the uplink data of the communication terminal 60 received in S414, the H-UPF 440 acquires the session information of the communication terminal 60 from the database 48 located on the cloud. The H-UPF 440 processes the data of the communication terminal 60 based on the session information of the communication terminal 60 acquired from the database 48.

[0280] 13 shows an example of the functional configuration of the H-SMF 420. The H-SMF 420 includes a request receiving unit 422, a session information generating unit 424, a storage unit 426, a registration unit 428, a session information synchronizing unit 430, and a response transmitting unit 432. It is not essential that the H-SMF 420 includes all of these components.

[0281] The request receiving unit 422 receives a session creation request from the communication terminal 60 requesting the creation of a session to the PDN 40. When the H-SMF 420 is selected as a transmission target of the session creation request from the communication terminal 60 from among the multiple H-SMFs included in the system 10, the request receiving unit 422 receives the session creation request from the communication terminal 60.

[0282] The request receiving unit 422 receives a session creation request from the communication terminal 60, for example, by using a router. If the H-SMF 420 has a router function, the request receiving unit 422 may receive a session creation request from the communication terminal 60 by using the router function of the H-SMF 420.

[0283] The session information generating unit 424 generates session information of the communication terminal 60. For example, the session information generating unit 424 generates session information of the communication terminal 60 in response to the request receiving unit 422 receiving a session generation request of the communication terminal 60. The session information generating unit 424 may store the generated session information of the communication terminal 60 in the storage unit 426.

[0284] The registration unit 428 registers in the storage unit the session information of the communication terminal 60 generated by the session information generation unit 424. For example, the registration unit 428 registers the session information of the communication terminal 60 in a database located at a base of the HPLMN. For example, the registration unit 428 registers the session information of the communication terminal 60 in a database located on a cloud.

[0285] The session information synchronization unit 430 synchronizes the session information of the communication terminal 60 registered in a database located at a base of the HPLMN by the registration unit 428 between that database and another database located at another base of the HPLMN. The session information synchronization unit 430 synchronizes the session information of the communication terminal 60 between that database and the other database using, for example, a Pub / Sub method. The session information synchronization unit 430 may also synchronize the session information of the communication terminal 60 between that database and the other database using any other method.

[0286] The response transmitting unit 432 transmits to the V-SMF 620 a session creation response of the communication terminal 60 in response to the session creation request of the communication terminal 60 received by the request receiving unit 422. The response transmitting unit 432 transmits to the V-SMF 620 the session creation response of the communication terminal 60, for example, in response to the session information generating unit 424 generating session information of the communication terminal 60. The response transmitting unit 432 transmits to the V-SMF 620 the session creation response of the communication terminal 60, for example, in response to the registration unit 428 registering the session information of the communication terminal 60 in the storage unit. The response transmitting unit 432 may transmit to the V-SMF 620 the session creation response of the communication terminal 60 in response to the session information synchronizing unit 430 synchronizing the session information of the communication terminal 60 between a database located at a base of the HPLMN and another database located at another base of the HPLMN.

[0287] The response transmitting unit 432 uses, for example, a router to transmit the session creation response of the communication terminal 60. If the H-SMF 420 has a router function, the response transmitting unit 432 may transmit the session creation response of the communication terminal 60 using the router function of the H-SMF 420.

[0288] 14 illustrates an example of the functional configuration of the H-UPF 440. The H-UPF 440 includes a data receiving unit 444, a session information acquiring unit 446, a storage unit 447, and a data transmitting unit 448. It is not essential that the H-UPF 440 includes all of these components.

[0289] The data receiving unit 444 receives data from the communication terminal 60. For example, when the H-UPF 440 is selected as a transmission target of the data from the communication terminal 60 from among the multiple H-UPFs included in the system 10, the data receiving unit 444 receives the data from the communication terminal 60.

[0290] The data receiving unit 444 receives uplink data of the communication terminal 60, for example, from the V-UPF 640. The data receiving unit 444 receives the uplink data of the communication terminal 60, for example, when the H-UPF 440 is selected as a transmission target of the uplink data of the communication terminal 60 from among a plurality of H-UPFs included in the system 10.

[0291] The data receiving unit 444 may receive the downlink data of the communication terminal 60 from a server arranged in the PDN 40. For example, when the H-UPF 440 is selected as a transmission target of the downlink data of the communication terminal 60 from among a plurality of H-UPFs included in the system 10, the data receiving unit 444 receives the downlink data of the communication terminal 60. In this case, the PDN 40 may be a private network.

[0292] The data receiving unit 444 receives data from the communication terminal 60 using, for example, a router. If the H-UPF 440 has a router function, the data receiving unit 444 may receive data from the communication terminal 60 using the router function of the H-UPF 440.

[0293] The session information acquisition unit 446 acquires session information of the communication terminal 60. For example, when the data receiving unit 444 receives data of the communication terminal 60, the session information acquisition unit 446 acquires the session information of the communication terminal 60. For example, when the data receiving unit 444 receives uplink data of the communication terminal 60, the session information acquisition unit 446 acquires the session information of the communication terminal 60. The session information acquisition unit 446 may acquire the session information of the communication terminal 60 when the data receiving unit 444 receives downlink data of the communication terminal 60.

[0294] For example, when the H-UPF 440 does not hold session information of the communication terminal 60, the session information acquisition unit 446 acquires session information of the communication terminal 60 from the storage unit. For example, when the data receiving unit 444 receives uplink data of the communication terminal 60 for the first time, the session information acquisition unit 446 acquires session information of the communication terminal 60 from the storage unit. When the data receiving unit 444 receives downlink data of the communication terminal 60 for the first time, the session information acquisition unit 446 may acquire session information of the communication terminal 60 from the storage unit. On the other hand, when the H-UPF 440 holds session information of the communication terminal 60, the session information acquisition unit 446 acquires session information of the communication terminal 60 from the storage unit 447.

[0295] When the H-SMF 420 and the H-UPF 440 share a storage unit, the storage unit 426 and the storage unit 447 may be the same member. On the other hand, when the H-SMF 420 and the H-UPF 440 have separate storage units, the storage unit 426 and the storage unit 447 may be different members.

[0296] The data transmission unit 448 transmits data of the communication terminal 60. The data transmission unit 448 transmits the data of the communication terminal 60 based on the session information of the communication terminal 60 acquired by the session information acquisition unit 446, for example.

[0297] The data transmission unit 448 transmits, for example, uplink data of the communication terminal 60. The data transmission unit 448 may transmit downlink data of the communication terminal 60.

[0298] The data transmission unit 448 transmits the data of the communication terminal 60 by using, for example, a router. If the H-UPF 440 has a router function, the data transmission unit 448 may transmit the data of the communication terminal 60 by using the router function of the H-UPF 440.

[0299] 15 shows an example of the functional configuration of the V-SMF 620. The V-SMF 620 includes a receiver 622, a generator 624, a storage unit 626, and a request transmitter 628. The receiver 622 includes a route information receiver 623, a request receiver 625, and a response receiver 627. It is not essential that the V-SMF 620 includes all of these components.

[0300] The receiving unit 622 receives various types of information. The receiving unit 622 may store the received various types of information in the storage unit 626.

[0301] The receiving unit 622 receives various information using, for example, a router. If the V-SMF 620 has a router function, the receiving unit 622 may receive various information using the router function of the V-SMF 620.

[0302] The route information receiving unit 623 receives route information. The route information receiving unit 623 receives route information from, for example, a router. The route information receiving unit 623 may receive route information from an IPX.

[0303] The generating unit 624 generates a route table. For example, the generating unit 624 generates the route table based on the route information received by the route information receiving unit 623. The generating unit 624 may store the generated route table in the storage unit 306.

[0304] The request receiving unit 625 receives a session creation request from the communication terminal 60 requesting the creation of a session to the PDN 40. The request receiving unit 625 receives the session creation request from the communication terminal 60 from an AMF corresponding to the V-SMF 620, for example.

[0305] The request transmitting unit 628 transmits a session creation request of the communication terminal 60. The request transmitting unit 628 transmits the session creation request of the communication terminal 60 in response to the request receiving unit 625 receiving the session creation request of the communication terminal 60, for example.

[0306] The request transmitting unit 628 transmits the session generation request of the communication terminal 60 to an H-SMF selected as a transmission target of the session generation request of the communication terminal 60 from among a plurality of H-SMFs included in the system 10 based on, for example, an H-SMF selection condition. The request transmitting unit 628 transmits the session generation request of the communication terminal 60 to an H-SMF having the shortest route to the V-SMF 620 among H-SMFs capable of transmitting the session generation request of the communication terminal 60. In this case, the H-SMF selection condition is that the V-SMF 620 has the shortest route to the V-SMF 620 among H-SMFs capable of transmitting the session generation request of the communication terminal 60.

[0307] The entity that selects the transmission target of the session generation request of the communication terminal 60 is, for example, a router. In this case, the request sending unit 628 may use the router to send the session generation request of the communication terminal 60 to the transmission target of the session generation request of the communication terminal 60.

[0308] When V-SMF 620 has a router function, the entity that selects the transmission target of the session creation request of communication terminal 60 may be V-SMF 620. In this case, request sending unit 628 may select the transmission target of the session creation request of communication terminal 60 according to a best path selection algorithm of BGP based on the route table stored in storage unit 626, and send the session creation request of communication terminal 60 to the selected transmission target of the session creation request of communication terminal 60.

[0309] The response receiving unit 627 receives a session creation response of the communication terminal 60 to the session creation request of the communication terminal 60 transmitted by the request transmitting unit 628. The response receiving unit 627 receives the session creation response of the communication terminal 60 from, for example, the H-SMF selected as a transmission target of the session creation request of the communication terminal 60.

[0310] 16 shows an example of a schematic functional configuration of the V-UPF 640. The V-UPF 640 includes a data receiving unit 644, a data transmitting unit 646, and a storage unit 647. Note that it is not essential that the V-UPF 640 includes all of these components.

[0311] The data receiving unit 644 receives uplink data of the communication terminal 60. The data receiving unit 644 receives the uplink data of the communication terminal 60 from the communication terminal 60, for example.

[0312] The data receiving unit 644 receives uplink data of the communication terminal 60, for example, by using a router. When the V-UPF 640 has a router function, the data receiving unit 644 may receive the uplink data of the communication terminal 60 by using the router function of the V-UPF 640.

[0313] The data transmitting unit 646 transmits uplink data of the communication terminal 60. The data transmitting unit 646 transmits, for example, the uplink data of the communication terminal 60 received by the data receiving unit 644. The data transmitting unit 315 transmits the uplink data of the communication terminal 60, for example, after the V-SMF 620 receives a session generation response from the communication terminal 60.

[0314] The data transmission unit 646 transmits the uplink data of the communication terminal 60 to an H-UPF selected as a transmission target of the uplink data of the communication terminal 60 from among a plurality of H-UPFs included in the system 10 based on, for example, an H-UPF selection condition. The data transmission unit 646 transmits the uplink data of the communication terminal 60 to an H-UPF having the shortest route to the V-UPF 640 among H-UPFs capable of transmitting a session generation request of the communication terminal 60. In this case, the H-UPF selection condition is that the V-UPF 640 has the shortest route to the V-UPF 640 among H-UPFs capable of transmitting a session generation request of the communication terminal 60.

[0315] The H-UPF selected as the transmission target of the uplink data of the communication terminal 60 is arranged in a network in which the H-SMF selected as the transmission target of the session generation request of the communication terminal 60 is arranged, for example. The H-UPF selected as the transmission target of the uplink data of the communication terminal 60 may be arranged in a network different from the network in which the H-SMF selected as the transmission target of the session generation request of the communication terminal 60 is arranged. In this case, for example, the H-SMF selected as the transmission target of the session generation request of the communication terminal 60 is arranged in a network of a first country, and the H-UPF selected as the transmission target of the uplink data of the communication terminal 60 is arranged in a network of a second country different from the first country. Both the H-UPF selected as the transmission target of the session generation request of the communication terminal 60 and the H-UPF selected as the transmission target of the uplink data of the communication terminal 60 may be arranged in the first country.

[0316] The entity that selects the transmission target of the uplink data of the communication terminal 60 is, for example, a router. In this case, the data transmitting unit 646 may transmit the uplink data of the communication terminal 60 to the transmission target of the uplink data of the communication terminal 60 using the router.

[0317] When the V-UPF 640 has a router function, the entity that selects the transmission target of the uplink data of the communication terminal 60 may be the V-UPF 640. In this case, the data transmitting unit 646 may select the transmission target of the uplink data of the communication terminal 60 according to a best path selection algorithm of BGP based on the route table stored in the storage unit 647, and transmit the uplink data of the communication terminal 60 to the selected transmission target of the uplink data of the communication terminal 60.

[0318] When V-SMF 620 and V-UPF 640 share a storage unit, storage unit 626 and storage unit 647 may be the same member. On the other hand, when V-SMF 620 and V-UPF 640 have separate storage units, storage unit 626 and storage unit 647 may be different members.

[0319] 17 is a schematic diagram showing an example of a hardware configuration of a computer 1200 functioning as a PGW 100, an SGW 300, an H-SMF 420, an H-UPF 440, a V-SMF 620, or a V-UPF 640. A program installed in the computer 1200 can cause the computer 1200 to function as one or more "parts" of the device according to the above embodiment, or cause the computer 1200 to execute operations or one or more "parts" associated with the device according to the above embodiment, and / or cause the computer 1200 to execute a process or steps of the process according to the above embodiment. Such a program can be executed by the CPU 1212 to cause the computer 1200 to execute specific operations associated with some or all of the blocks of the flowcharts and block diagrams described herein.

[0320] The computer 1200 according to this embodiment includes a CPU 1212, a RAM 1214, and a graphics controller 1216, which are connected to each other by a host controller 1210. The computer 1200 also includes input / output units such as a communication interface 1222, a storage device 1224, a DVD drive 1226, and an IC card drive, which are connected to the host controller 1210 via an input / output controller 1220. The DVD drive 1226 may be a DVD-ROM drive, a DVD-RAM drive, or the like. The storage device 1224 may be a hard disk drive, a solid state drive, or the like. The computer 1200 also includes legacy input / output units such as a ROM 1230 and a keyboard 1242, which are connected to the input / output controller 1220 via an input / output chip 1240.

[0321] The CPU 1212 operates according to a program stored in the ROM 1230 and the RAM 1214, thereby controlling each unit. The graphic controller 1216 acquires image data generated by the CPU 1212 into a frame buffer or the like provided in the RAM 1214 or into itself, and causes the image data to be displayed on the display device 1218.

[0322] The communication interface 1222 communicates with other electronic devices via a network. The storage device 1224 stores programs and data used by the CPU 1212 in the computer 1200. The DVD drive 1226 reads programs or data from a DVD-ROM 1227 or the like and provides the programs or data to the storage device 1224. The IC card drive reads programs and data from an IC card and / or writes programs and data to an IC card.

[0323] The ROM 1230 stores therein a boot program or the like that is executed by the computer 1200 upon activation, and / or a program that depends on the hardware of the computer 1200. The input / output chip 1240 may also connect various input / output units to the input / output controller 1220 via a USB port, a parallel port, a serial port, a keyboard port, a mouse port, and the like.

[0324] The programs are provided by a computer-readable storage medium such as a DVD-ROM 1227 or an IC card. The programs are read from the computer-readable storage medium, installed in the storage device 1224, the RAM 1214, or the ROM 1230, which are also examples of computer-readable storage media, and executed by the CPU 1212. Information processing described in these programs is read by the computer 1200, and brings about cooperation between the programs and the various types of hardware resources described above. An apparatus or method may be constructed by implementing operations or processing of information according to the use of the computer 1200.

[0325] For example, when communication is performed between the computer 1200 and an external device, the CPU 1212 may execute a communication program loaded in the RAM 1214 and instruct the communication interface 1222 to perform communication processing based on the processing described in the communication program. Under the control of the CPU 1212, the communication interface 1222 reads transmission data stored in a transmission buffer area provided in the RAM 1214, the storage device 1224, the DVD-ROM 1227, or a recording medium such as an IC card, and transmits the read transmission data to a network, or writes reception data received from the network to a reception buffer area or the like provided on the recording medium.

[0326] Furthermore, the CPU 1212 may cause all or a necessary portion of a file or database stored in an external recording medium such as the storage device 1224, the DVD drive 1226 (DVD-ROM 1227), an IC card, etc. to be read into the RAM 1214, and perform various types of processing on the data on the RAM 1214. The CPU 1212 may then write back the processed data to the external recording medium.

[0327] Various types of information, such as various types of programs, data, tables, and databases, may be stored in the recording medium and undergo information processing. The CPU 1212 may perform various types of processing on the data read from the RAM 1214, including various types of operations, information processing, conditional judgment, conditional branching, unconditional branching, information search / replacement, etc., as described throughout this disclosure and specified by the instruction sequence of the program, and write back the results to the RAM 1214. The CPU 1212 may also search for information in a file, database, etc. in the recording medium. For example, when a plurality of entries each having an attribute value of a first attribute associated with an attribute value of a second attribute are stored in the recording medium, the CPU 1212 may search for an entry whose attribute value of the first attribute matches a specified condition from among the plurality of entries, read the attribute value of the second attribute stored in the entry, and thereby obtain the attribute value of the second attribute associated with the first attribute that satisfies a predetermined condition.

[0328] The above-described programs or software modules may be stored in a computer-readable storage medium on the computer 1200 or in the vicinity of the computer 1200. In addition, a recording medium such as a hard disk or a RAM provided in a server system connected to a dedicated communication network or the Internet can be used as a computer-readable storage medium, thereby providing the programs to the computer 1200 via the network.

[0329] The blocks in the flowcharts and block diagrams in the present embodiment may represent stages of a process in which an operation is performed or "parts" of an apparatus responsible for performing the operation. Particular stages and "parts" may be implemented by dedicated circuitry, programmable circuitry provided with computer-readable instructions stored on a computer-readable storage medium, and / or a processor provided with computer-readable instructions stored on a computer-readable storage medium. The dedicated circuitry may include digital and / or analog hardware circuits, and may include integrated circuits (ICs) and / or discrete circuits. The programmable circuitry may include reconfigurable hardware circuits, such as, for example, field programmable gate arrays (FPGAs), programmable logic arrays (PLAs), and the like, including AND, OR, XOR, NAND, NOR, and other logical operations, flip-flops, registers, and memory elements.

[0330] A computer-readable storage medium may include any tangible device capable of storing instructions that are executed by a suitable device, such that a computer-readable storage medium having instructions stored thereon comprises an article of manufacture that includes instructions that can be executed to create means for performing the operations specified in the flowcharts or block diagrams. Examples of computer-readable storage media may include electronic storage media, magnetic storage media, optical storage media, electromagnetic storage media, semiconductor storage media, and the like. More specific examples of computer-readable storage media may include floppy disks, diskettes, hard disks, random access memories (RAMs), read-only memories (ROMs), erasable programmable read-only memories (EPROMs or flash memories), electrically erasable programmable read-only memories (EEPROMs), static random access memories (SRAMs), compact disk read-only memories (CD-ROMs), digital versatile disks (DVDs), Blu-ray disks, memory sticks, integrated circuit cards, and the like.

[0331] The computer readable instructions may include either assembler instructions, instruction set architecture (ISA) instructions, machine instructions, machine-dependent instructions, microcode, firmware instructions, state setting data, or source or object code written in any combination of one or more programming languages, including object-oriented programming languages ​​such as Smalltalk®, JAVA®, C++, etc., and conventional procedural programming languages ​​such as the “C” programming language or similar programming languages.

[0332] Computer readable instructions may be provided to a processor of a general purpose computer, special purpose computer, or other programmable data processing apparatus, or to a programmable circuit, either locally or over a local area network (LAN), a wide area network (WAN), such as the Internet, etc., to cause the processor of the general purpose computer, special purpose computer, or other programmable data processing apparatus, or to a programmable circuit, to execute the computer readable instructions to generate means for performing the operations specified in the flowcharts or block diagrams. Examples of processors include computer processors, processing units, microprocessors, digital signal processors, controllers, microcontrollers, etc.

[0333] Although the present invention has been described above using the embodiments, the technical scope of the present invention is not limited to the scope described in the above embodiments. It is clear to those skilled in the art that various modifications and improvements can be made to the above embodiments. It is clear from the description of the claims that such modifications and improvements can also be included in the technical scope of the present invention.

[0334] It should be noted that the order of execution of each process, such as operations, procedures, steps, and stages, in the devices, systems, programs, and methods shown in the claims, specifications, and drawings is not specifically stated as "before" or "prior to," and that the process may be performed in any order unless the output of a previous process is used in a later process. Even if the operational flow in the claims, specifications, and drawings is described using "first," "next," etc. for convenience, it does not mean that the process must be performed in this order. [Explanation of symbols]

[0335] 10 system, 12 network, 13 network, 14 network, 15 network, 22 router, 23 router, 24 router, 25 router, 26 router, 27 router, 32 database, 33 database, 34 database, 35 database, 40 PDN, 48 database, 60 communication terminal, 82 router, 83 router, 84 router, 85 router, 100 PGW, 103 request receiving unit, 104 session information generating unit, 106 storage unit, 108 registration unit, 110 session information synchronization unit, 112 response transmitting unit, 113 data receiving unit, 114 session information acquiring unit, 116 data transmitting unit, 120 PGW-C, 140 PGW-U, 200 PGW, 220 PGW-C, 240 PGW-U, 300 SGW, 302 receiving unit, 303 Route information receiving unit, 304, generating unit, 305, request receiving unit, 306, storing unit, 307, response receiving unit, 309, data receiving unit, 312, transmitting unit, 313, request transmitting unit, 315, data transmitting unit, 320, SGW-C, 340, SGW-U, 420, H-SMF, 422, request receiving unit, 424, session information generating unit, 426, storing unit, 428, registration unit, 430, session information synchronization unit, 432, response transmitting unit, 440, H-UPF, 444, data receiving unit, 446, session information acquisition unit, 447, storing unit, 448, data transmitting unit, 520, H-SMF, 540, H-UPF, 620, V-SMF, 622, receiving unit, 623, route information receiving unit, 624, generating unit, 625, request receiving unit, 626, storing unit, 627 Response receiving unit, 628 request sending unit, 640 V-UPF, 644 data receiving unit, 646 data sending unit, 647 storage unit, 700 resource management device, 1200 computer, 1210 host controller, 1212 CPU, 1214 RAM, 1216 graphic controller, 1218 display device, 1220 input / output controller, 1222 communication interface, 1224 storage device, 1226 DVD drive, 1227 DVD-ROM, 1230 ROM, 1240 input / output chip, 1242 keyboard

Claims

1. SGW (Serving Gateway), A plurality of PGWs (Packet data network Gateways); Memory section and Equipped with Each PGW of the plurality of PGWs is located in a network having a different ASN (Autonomous System number), and each PGW is assigned the same IP (Internet Protocol) address; The SGW, A request transmission unit that transmits a session generation request of a communication terminal requesting generation of a session to a PDN (Packet Data Network) to a PGW selected as a transmission target of the session generation request from among the plurality of PGWs based on a predetermined PGW selection condition. having The PGW selected as the transmission target of the session creation request, a request receiving unit for receiving the session creation request; a session information generation unit that generates session information of the communication terminal, the session information including an IP address of the communication terminal, the IP address of the PGW, a TEID (Tunnel Endpoint IDentifier) ​​assigned to a communication tunnel of each of the PGWs, an IP address of the SGW, and a TEID assigned to a communication tunnel of the SGW, in response to the request reception unit receiving the session creation request; a registration unit that registers the session information generated by the session information generation unit in the storage unit; a response transmission unit that transmits a session generation response of the communication terminal to the SGW in response to the session information generation unit generating the session information; having The SGW, a response receiving unit for receiving the session creation response; a data transmission unit that transmits uplink data of the communication terminal to a PGW selected as a transmission target of the uplink data from among the plurality of PGWs based on the PGW selection condition after the response reception unit receives the session creation response; and The PGW selected as the transmission target of the uplink data, A first data receiving unit for receiving the uplink data; a first session information acquisition unit that acquires the session information from the storage unit when the first data receiving unit receives the uplink data and the PGW does not hold the session information; The system has:

2. The system according to claim 1 , wherein the PGW selected as the transmission target of the uplink data is the same PGW as the PGW selected as the transmission target of the session creation request.

3. The system according to claim 1 , wherein the PGW selected as the transmission target of the uplink data is a PGW different from the PGW selected as the transmission target of the session creation request.

4. 4. The system according to claim 3, wherein the PGW selected as the transmission target of the session generation request is located in the network of a first country, and the PGW selected as the transmission target of the uplink data is located in the network of a second country different from the first country.

5. The system according to claim 1 , wherein the first session information acquisition unit acquires the session information from the storage unit when the first data receiving unit receives the uplink data for the first time.

6. A PGW that is a transmission target of downlink data of the communication terminal among the plurality of PGWs, A second data receiving unit for receiving the downlink data; a second session information acquisition unit that acquires the session information from the storage unit when the second data receiving unit receives the downlink data and the PGW does not hold the session information; The system according to claim 1 , further comprising:

7. The SGW is divided into SGW-C (SGW-Control plane function) and SGW-U (SGW-User plane function), Each of the multiple PGWs is separated into a PGW-C (PGW-Control plane function) and a PGW-U (PGW-User plane function), each PGW-C is assigned the same IP address, and each PGW-U is assigned the same IP address, the IP address of the PGW includes the IP address of the PGW-C and the IP address of the PGW-U, which is different from the IP address of the PGW-C; the TEIDs assigned to the communication tunnels of each of the PGWs include a TEID assigned to the communication tunnels of each of the PGW-Cs and a TEID assigned to the communication tunnels of each of the PGW-Us and different from the TEIDs assigned to the communication tunnels of each of the PGW-Cs; The IP address of the SGW includes an IP address of the SGW-C and an IP address of the SGW-U that is different from the IP address of the SGW-C; The TEID assigned to the communication tunnel of the SGW includes a TEID assigned to the communication tunnel of the SGW-C and a TEID assigned to the communication tunnel of the SGW-U and different from the TEID assigned to the communication tunnel of the SGW-C. A system according to any one of claims 1 to 4.

8. The storage unit is located on a cloud, Each of the plurality of PGWs is capable of accessing the memory unit. A system according to any one of claims 1 to 4.

9. V-SMF (Visited Session Management Function); A V-UPF (Visited User Plane Function) disposed in a network in which the V-SMF is disposed; A plurality of H-SMFs (Home Session Management Functions); A plurality of H-UPFs (Home User Plane Functions); Memory section and Equipped with Each H-SMF of the plurality of H-SMFs is located in a network having a different ASN, and each H-SMF is assigned the same IP address; Each H-UPF of the plurality of H-UPFs is located in a network having a different ASN, and each H-UPF is assigned the same IP address; The V-SMF is A request transmission unit that transmits a session generation request of a communication terminal requesting generation of a session to a PDN to an H-SMF selected as a transmission target of the session generation request from among the plurality of H-SMFs based on a predetermined H-SMF selection condition. having The H-SMF selected as the transmission target of the session creation request, a request receiving unit for receiving the session creation request; a session information generating unit that generates, in response to the request receiving unit receiving the session creation request, session information of the communication terminal, including an IP address of the communication terminal, the IP address of the H-SMF, the IP address of the H-UPF different from the IP address of the H-SMF, a TEID assigned to a communication tunnel of each of the H-SMFs, a TEID assigned to a communication tunnel of each of the H-UPFs and different from the TEID assigned to the communication tunnel of each of the H-SMFs, an IP address of the V-SMF, an IP address of the V-UPF different from the IP address of the V-SMF, a TEID assigned to a communication tunnel of the V-SMF, and a TEID assigned to a communication tunnel of the V-UPF and different from the TEID assigned to the communication tunnel of the V-SMF; a registration unit that registers the session information generated by the session information generation unit in the storage unit; a response transmission unit that transmits a session generation response of the communication terminal to the V-SMF in response to the session information generation unit generating the session information; having The V-SMF is A response receiving unit for receiving the session creation response and The V-UPF is a data transmission unit that transmits uplink data of the communication terminal to an H-UPF selected as a transmission target of the uplink data from among the plurality of H-UPFs based on a predetermined H-UPF selection condition after the V-SMF receives the session creation response. having The H-UPF selected as the transmission target of the uplink data, A data receiving unit for receiving the uplink data; a session information acquisition unit that acquires the session information from the storage unit when the H-UPF does not hold the session information when the data receiving unit receives the uplink data; The system has:

10. A method executed by a system comprising: an SGW; a plurality of PGWs; and a storage unit, wherein each PGW of the plurality of PGWs is located in a network having a different ASN, and each PGW is assigned an identical IP address, A request transmission step in which the SGW transmits a session generation request of a communication terminal requesting generation of a session to a PDN to a PGW selected as a transmission target of the session generation request from among the plurality of PGWs based on a predetermined PGW selection condition; a request receiving step in which the PGW selected as the transmission target of the session creation request receives the session creation request; a session information generation step of generating session information of the communication terminal, the session information including an IP address of the communication terminal, the IP address of the PGW, a TEID assigned to a communication tunnel of each of the PGWs, an IP address of the SGW, and a TEID assigned to a communication tunnel of the SGW, in response to the PGW selected as the transmission target of the session creation request receiving the session creation request in the request receiving step; a registration step in which the PGW selected as the transmission target of the session creation request registers the session information generated in the session information generation step in the storage unit; A response transmission step in which the PGW selected as the transmission target of the session creation request transmits a session creation response of the communication terminal to the SGW in response to the session information being generated in the session information generation step; a response receiving step of the SGW receiving the session creation response; A data transmission step of transmitting uplink data of the communication terminal to a PGW selected as a transmission target of the uplink data from among the plurality of PGWs based on the PGW selection condition after the SGW receives the session creation response in the response reception step; A data receiving step in which the PGW selected as the transmission target of the uplink data receives the uplink data; a session information acquisition step of acquiring the session information from the storage unit when the PGW selected as the transmission target of the uplink data receives the uplink data in the data reception step and the PGW does not hold the session information; A method comprising:

11. A method executed by a system comprising: a V-SMF; a V-UPF arranged in a network in which the V-SMF is arranged; a plurality of H-SMFs; a plurality of H-UPFs; and a memory unit, wherein each H-SMF of the plurality of H-SMFs is arranged in a network with a different ASN and each H-SMF is assigned the same IP address, and each H-UPF of the plurality of H-UPFs is arranged in a network with a different ASN and each H-UPF is assigned the same IP address, A request transmission step in which the V-SMF transmits a session creation request of a communication terminal requesting the creation of a session to a PDN to an H-SMF selected as a destination of the session creation request from among the plurality of H-SMFs based on a predetermined H-SMF selection condition; a request receiving step in which the H-SMF selected as the transmission target of the session creation request receives the session creation request; a session information generation step of generating session information of the communication terminal, the session information including an IP address of the communication terminal, the IP address of the H-SMF, the IP address of the H-UPF different from the IP address of the H-SMF, a TEID assigned to a communication tunnel of each of the H-SMFs, a TEID assigned to a communication tunnel of each of the H-UPFs and different from the TEID assigned to the communication tunnel of each of the H-SMFs, an IP address of the V-SMF, an IP address of the V-UPF different from the IP address of the V-SMF, a TEID assigned to a communication tunnel of the V-SMF, and a TEID assigned to a communication tunnel of the V-UPF and different from the TEID assigned to the communication tunnel of the V-SMF; a registration step in which the H-SMF selected as the transmission target of the session creation request registers the session information generated in the session information generation step in the storage unit; a response transmission step in which the H-SMF selected as the transmission target of the session creation request transmits a session creation response of the communication terminal to the V-SMF in response to the session information being generated in the session information generation step; a response receiving step of the V-SMF receiving the session creation response; a data transmission step of the V-UPF transmitting uplink data of the communication terminal to an H-UPF selected as a transmission target of the uplink data from among the plurality of H-UPFs based on a predetermined H-UPF selection condition after the V-SMF receives the session creation response in the response receiving step; a data receiving step in which the H-UPF selected as the transmission target of the uplink data receives the uplink data; a session information acquisition step of acquiring the session information from the storage unit when the H-UPF selected as the transmission target of the uplink data receives the uplink data in the data reception step and the H-UPF does not hold the session information; A method comprising:

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