Wireless communication system and communication method

Abstract

A wireless communication system (1) comprises a closed system (11) and a cloud system (21). A closed system (11) comprises: a call control server (12) that controls communications of wireless stations (41, 42) connected to a closed network (10) and an Internet network (20), respectively; a closed-side gateway server (13) that transmits a registration request from the wireless station (41) to the call control server (12) and transmits a registration response from the call control server (12) to the wireless station (41); and a closed-side DNS server (14) that performs name resolution upon receiving a name resolution request from the wireless station (41). The cloud system (21) comprises a cloud-side gateway server (22) that transmits a registration request from the wireless station (42) to the call control server (12) and transmits a registration response from the call control server (12) to the wireless station (42).

Description

Wireless communication system and communication method

[0001] The present invention relates to a wireless communication system and a communication method.

[0002] In order for communication devices connected to different networks, such as a local area network (LAN) and a wide area network (WAN), to communicate with each other, a gateway device is provided between the different networks. Patent Literature 1 discloses an example of a communication device that communicates with other communication devices connected to different networks via a gateway device.

[0003] The voice communication system disclosed in Patent Document 1 includes a gateway device that connects a LAN and LTE (Long Term Evolution), a mobile phone communication network, and relays communication between a LAN communication terminal connected to the LAN and an LTE communication terminal connected to the LTE.

[0004] International Publication No. 2017 / 006833

[0005] The LTE communication terminal disclosed in Patent Document 1 is capable of communicating with LAN communication terminals, but is unable to communicate with communication terminals connected to the Internet via a LAN.

[0006] The present invention has been made in consideration of the above circumstances, and an object of the present invention is to provide a wireless communication system and a communication method that enable communication between a wireless station connected to an Internet network and a wireless station connected to a closed network.

[0007] In order to achieve the above object, a wireless communication system according to a first aspect of the present invention comprises a closed system provided in a closed network and a cloud system provided in an Internet network, the closed system and the cloud system being connected to each other so as to be able to communicate with each other, the closed system comprising: a call control server that controls communication between a plurality of wireless stations, each of which is connected to either the closed network or the Internet network; a closed-side gateway server that holds correspondence between the wireless stations and the call control server, and that, upon receiving a registration request or voice data from a wireless station connected to the closed network, transmits the registration request or the voice data to the call control server associated with the wireless station, and, upon receiving a registration response or voice data from the call control server, transmits the registration response or the voice data to the wireless station that is the destination; and a closed-side DNS server that, upon receiving a name resolution request for a domain name of a closed-side device included in the closed system or a cloud-side device included in the cloud system from the wireless station connected to the closed network, performs name resolution of the domain name included in the name resolution request, and transmits a name resolution response including an address corresponding to the domain name to the wireless station, the cloud system comprising: The cloud-side gateway server maintains correspondence between the wireless station and the call control server, and when receiving a registration request or voice data from the wireless station connected to the Internet network, transmits the registration request or voice data to the call control server associated with the wireless station, and when receiving a registration response or voice data addressed to the wireless station connected to the Internet network from the call control server, transmits the registration response or voice data to the wireless station.

[0008] Preferably, when the closed-side DNS server receives the name resolution request of the closed-side gateway server, which is the closed-side device, from the wireless station connected to the closed network, it transmits the name resolution response including the address of the closed-side gateway server to the wireless station.

[0009] Preferably, the closed system further includes a closed-side activation server that, when it receives an activation request from a wireless station connected to the closed network as the closed-side device, registers activation information including information that uniquely identifies the wireless station in a storage device provided in each of the closed system and the cloud system.

[0010] Preferably, when the closed-side DNS server receives the name resolution request of the closed-side activation server, which is the closed-side device, from the wireless station connected to the closed network, it transmits the name resolution response including the address of the closed-side activation server to the wireless station.

[0011] Preferably, the cloud system further includes a cloud-side activation server that, when it receives an activation request from a wireless station connected to the Internet network, the activation request includes unique information that uniquely identifies the wireless station, registers the activation information including the unique information in a storage device provided in each of the closed system and the cloud system.

[0012] Preferably, the cloud system further includes, as the cloud-side device, a cloud-side provisioning server that, upon receiving a provisioning request from a wireless station connected to the closed network, transmits a provisioning response including a domain name of the closed-network gateway server to the wireless station, and that, upon receiving a provisioning request from a wireless station connected to the Internet network, transmits a provisioning response including a domain name of the cloud-side gateway server to the wireless station.

[0013] Preferably, the cloud system further includes a dedicated connection device that connects each of the cloud side devices to the closed side device and the closed network via a dedicated line, the dedicated connection device transfers data received from the wireless station or the closed side device connected to the closed network to the cloud side device according to the type of data, and when the closed side DNS server receives the name resolution request for the domain name of the cloud side provisioning server from the wireless station, it transmits the name resolution response including the address of the dedicated connection device to the wireless station.

[0014] Preferably, the cloud system further includes a dedicated connection device that connects each of the cloud side devices to the closed side device and the closed network via a dedicated line, and the dedicated connection device transfers data received from the wireless station or the closed side device connected to the closed network to the cloud side device according to the type of data.

[0015] Preferably, the cloud system further includes an endpoint device that connects each of the cloud-side devices to the Internet network, and an Internet DNS server provided in the Internet network, upon receiving a name resolution request for the cloud-side device from the wireless station connected to the Internet network, transmits a name resolution response including the address of the endpoint device to the wireless station, and the endpoint device transfers data received from the wireless station connected to the Internet network to the cloud-side device according to the type of data.

[0016] Preferably, the call control server controls communication between at least one first wireless station that can be connected to both the closed network and the Internet network and at least one second wireless station that can be connected only to the closed network, and the closed system further has a closed-side provisioning server that, upon receiving a provisioning request from the second wireless station connected to the closed network, transmits a provisioning response including the address of the call control server to the second wireless station.

[0017] Preferably, the call control server controls communication of the associated wireless station whether the wireless station is connected to the closed network or the Internet network.

[0018] Preferably, the system includes a plurality of closed systems that are connected to each other so that they can communicate with each other via the cloud system, and when the call control server of one of the closed systems becomes unable to control communication between the plurality of wireless stations, the call control server of another of the closed systems controls communication between the plurality of wireless stations.

[0019] A communication method according to a second aspect of the present invention is a wireless communication system comprising a closed system provided in a closed network and a cloud system provided in an Internet network, the closed system and the cloud system being connected to each other so as to be able to communicate with each other, the closed system having a call control server that controls communication between a plurality of wireless stations each connected to either the closed network or the Internet network, a closed-side gateway server that holds correspondence between the wireless stations and the call control servers, and a closed-side DNS server that performs name resolution processing, the cloud system having a cloud-side gateway server that holds correspondence between the wireless stations and the call control servers, the communication method being performed by the wireless communication system, wherein, upon receiving a registration request or voice data from a wireless station connected to the closed network, the closed-side gateway server transmits the registration request or the voice data to the call control server that is associated with the wireless station, and upon receiving a registration response or voice data from the call control server, the closed-side DNS server transmits the registration response or the voice data to the wireless station that is the destination When a name resolution request for a domain name of a closed-side device included in the closed system or a cloud-side device included in the cloud system is received from the wireless station connected to the closed network, name resolution of the domain name included in the name resolution request is performed, and a name resolution response including an address corresponding to the domain name is transmitted to the wireless station; the cloud-side gateway server maintains a correspondence between the wireless station and the call control server; when a registration request or voice data is received from the wireless station connected to the Internet network, the cloud-side gateway server transmits the registration request or the voice data to the call control server associated with the wireless station; and when a registration response or voice data addressed to the wireless station connected to the Internet network is received from the call control server, the cloud-side gateway server transmits the registration response or the voice data to the wireless station.

[0020] The closed-side DNS server provided in the wireless communication system of the present invention performs name resolution, the closed-side gateway server transmits a registration request or voice data to the call control server associated with the wireless station, and the cloud-side gateway server transmits the registration request or voice data to the call control server associated with the wireless station, thereby enabling communication between wireless stations connected to the closed network and wireless stations connected to the Internet network.

[0021] 1 is a block diagram showing a configuration of a wireless communication system according to a first embodiment; 2 is a block diagram showing a configuration of a wireless station according to the first embodiment; 3 is a flow chart showing an example of a startup process performed by a wireless station according to the first embodiment; 4 is a sequence diagram showing an example of an activation process performed by a wireless communication system according to the first embodiment; 5 is a sequence diagram showing an example of a provisioning process performed by a wireless communication system according to the first embodiment; 6 is a sequence diagram showing an example of a registration process performed by a wireless communication system according to the first embodiment;

[0022] A wireless communication system and a communication method according to an embodiment of the present invention will be described in detail below with reference to the drawings, in which the same or equivalent parts are designated by the same reference numerals.

[0023] (First Embodiment) A wireless communication system 1 shown in Fig. 1 relays communications between wireless stations 41 and 42 connected to either a closed network 10 or an Internet network 20. In the first embodiment, the wireless stations 41 and 42 are IP (Internet Protocol) transceivers that perform voice communications. The wireless stations 41 and 42 have the same configuration and function. In the example of Fig. 1, the wireless station 41 is connected to the closed network 10 via a base station 31, and the wireless station 42 is connected to the Internet network 20 via a WLAN (Wireless Local Area Network) device 32. The WLAN device 32 is, for example, an access point device.

[0024] The wireless communication system 1 includes a closed system 11 provided in a closed network 10 and a cloud system 21 provided in an Internet network 20. The closed system 11 includes a call control server 12, a closed-side gateway server 13, a closed-side DNS (Domain Name System) server 14, a closed-side activation server 15, a router 16, and a storage device 17. The cloud system 21 includes a cloud-side gateway server 22, a cloud-side provisioning server 23, a cloud-side activation server 24, an endpoint device 25, a dedicated connection device 26, and a storage device 27.

[0025] The closed system 11 and the cloud system 21 are connected to each other via a dedicated line. The dedicated connection device 26 connects each of the cloud-side devices included in the cloud system 21 to the closed-side devices included in the closed system 11 and the closed network 10 via a dedicated line. The closed-side devices are the components of the closed system 11 described above, specifically the call control server 12, the closed-side gateway server 13, the closed-side DNS server 14, the closed-side activation server 15, the router 16, and the storage device 17. The cloud-side devices are the components of the cloud system 21, specifically the cloud-side gateway server 22, the cloud-side provisioning server 23, the cloud-side activation server 24, the endpoint device 25, the dedicated connection device 26, and the storage device 27. Note that the term "device" refers to not only physically existing devices but also virtual devices.

[0026] The closed system 11 includes any number of call control servers 12. Each call control server 12 controls communications between the wireless stations 41 and 42, specifically, controls calls such as voice transmission and reception.

[0027] The closed-side gateway server 13 holds a correspondence between the wireless station 41 and the call control server 12. As an example, the closed-side gateway server 13 holds a table that associates unique information that uniquely identifies the wireless station 41 with the address of the call control server 12. The unique information that uniquely identifies the wireless station 41 is, for example, an IMEI (International Mobile Equipment Identifier) ​​or an ICCID (Integrated Circuit Card Identifier), which is the identification number of a SIM (Subscriber Identity Module) card inserted in the wireless station 41.

[0028] When the closed-side gateway server 13 receives a registration request or voice data from a wireless station 41 connected to the closed network 10 via the router 16, it transmits the received registration request or voice data to the call control server 12 associated with the wireless station 41. When the closed-side gateway server 13 receives a registration response or voice data from the call control server 12, it transmits the received registration response or voice data to the destination wireless station 41 via the router 16.

[0029] The closed-side DNS server 14 performs name resolution for closed-side devices included in the closed system 11 and for cloud-side devices included in the cloud system 21. The closed-side devices that are the targets of name resolution by the closed-side DNS server 14 are, for example, the closed-side gateway server 13 and the closed-side activation server 15. The cloud-side device that is the target of name resolution by the closed-side DNS server 14 is, for example, the dedicated connection device 26.

[0030] In detail, when the closed-side DNS server 14 receives a name resolution request for the domain name of a closed-side device included in the closed system 11 or a cloud-side device included in the cloud system 21 from a wireless station 41 connected to the closed network 10, the closed-side DNS server 14 performs name resolution of the domain name included in the name resolution request and transmits a name resolution response including an address corresponding to the domain name to the wireless station 41.

[0031] When the closed-side activation server 15 receives an activation request from a wireless station 41 connected to the closed network 10, it registers activation information including the wireless station 41's unique information in storage devices 17, 27 provided in the closed system 11 and the cloud system 21, respectively.

[0032] The storage device 17 is a DB server, for example, a NoSQL server, that stores activation information.

[0033] The router 16 transmits data received from the cloud system 21 or the closed network 10 to a closed-side device included in the closed system 11 according to the destination of the data.

[0034] The dedicated connection device 26 has, for example, a virtual interface connected by a dedicated line to the closed system 11 and the closed network 10. The dedicated connection device 26 transmits data received from the closed system 11 or the closed network 10 having the above configuration to a cloud-side device included in the cloud system 21 according to the type of the data.

[0035] Specifically, data transmitted from a wireless station 41 connected to the closed network 10 or a closed-side device included in the closed system 11 reaches the dedicated connection device 26. The dedicated connection device 26 transfers the received data to a cloud-side device according to the type of data. When the dedicated connection device 26 receives a provisioning request from the wireless station 41, it transfers the provisioning request to the cloud-side provisioning server 23 via a load balancer (not shown).

[0036] Furthermore, the dedicated connection device 26 transmits data received from cloud-side devices included in the cloud system 21 to the closed system 11 or the closed network 10 via the virtual interface.

[0037] The endpoint device 25 has an interface connected to the Internet network 20. The endpoint device 25 transmits data received from the Internet network 20 to each device in the cloud system 21. In particular, the endpoint device 25 forwards various requests received from the Internet network 20, specifically, activation requests, provisioning requests, and registration requests, to a device corresponding to the request type, i.e., the cloud-side activation server 24, the cloud-side provisioning server 23, and the cloud-side gateway server 22. The endpoint device 25 also forwards data addressed to the wireless station 42 received from each device in the cloud system 21 to the wireless station 42 via the Internet network 20.

[0038] The cloud-side gateway server 22 holds a correspondence between the wireless station 42 and the call control server 12. As an example, the cloud-side gateway server 22 holds a table that associates unique information that uniquely identifies the wireless station 42 with the address of the call control server 12. The unique information that uniquely identifies the wireless station 42 is, for example, the IMEI, an ICCID that is the identification number of the SIM card inserted in the wireless station 42, or the like.

[0039] When the cloud-side gateway server 22 receives a registration request or voice data from a wireless station 42 connected to the Internet network 20, it transmits the received registration request or voice data to the call control server 12 associated with the wireless station 42. When the cloud-side gateway server 22 receives a registration response or voice data from the call control server 12, it transmits the received registration response or voice data to the wireless station 42 that is the destination.

[0040] When the cloud-side provisioning server 23 receives a provisioning request from the wireless stations 41 and 42, it transmits a provisioning response including the domain name of the gateway server to the wireless stations 41 and 42.

[0041] When the cloud-side activation server 24 receives an authentication request from a wireless station 42 connected to the Internet network 20, the activation information including the wireless station 42's unique information and encryption key generation information is stored in a storage device provided in at least one of the closed system 11 and the cloud system 21, for example, in storage devices 17 and 27 provided in the closed system 11 and the cloud system 21, respectively.

[0042] The storage device 27 is a DB server, for example, a NoSQL server, that stores activation information.

[0043] 2 shows the configuration of wireless stations 41, 42 that communicate via the wireless communication system 1 having the above configuration. Each of the wireless stations 41, 42 includes an LTE communication circuit 51, a WLAN communication circuit 52, a communication control circuit 53, a data processing circuit 54, an input circuit 55, and an output circuit 56. The LTE communication circuit 51 connects to the closed network 10 and transmits and receives closed network data that conforms to the communication standard of the closed network 10. The WLAN communication circuit 52 connects to the Internet network 20 via the WLAN device 32 and transmits and receives communication data that conforms to the communication standard of the Internet network 20. The communication control circuit 53 controls the LTE communication circuit 51 and the WLAN communication circuit 52 to establish voice communication.

[0044] The data processing circuit 54 generates, from the transmission data generated by the input circuit 55, closed network data to be transmitted from the LTE communication circuit 51 or communication data to be transmitted from the WLAN communication circuit 52. The data processing circuit 54 also generates reception data from the closed network data received by the LTE communication circuit 51 or the communication data received by the WLAN communication circuit 52, and outputs the reception data to the output circuit 56.

[0045] The input circuit 55 acquires audio from a microphone (not shown), performs signal processing such as A-D (Analog-to-Digital) conversion, noise filtering, and amplification, generates data to be transmitted, and sends the generated data to the data processing circuit 54.

[0046] The output circuit 56 performs signal processing such as noise filtering, amplification, and D-A (Digital-to-Analog) conversion on the received data acquired from the data processing circuit 54 to generate audio data, and outputs the generated audio data from a speaker (not shown). The output circuit 56 may also acquire processing results such as activation, provisioning, and registration from the data processing circuit 54 and display them on a screen (not shown).

[0047] When the wireless stations 41 and 42 having the above configuration are started, for example, when the power is turned on, the start-up process shown in Fig. 3 is initiated. By performing the start-up process, the wireless stations 41 and 42 can start voice communication.

[0048] The following describes the startup process performed by the wireless station 41 connected to the private network 10. The wireless station 41 performs activation, which is a setting for starting use of the wireless station 41 (step S11).

[0049] Details of the activation process performed by the wireless station 41 are shown in Figure 4. The wireless station 41 transmits a name resolution request including the domain name of the closed-side activation server 15, which is the destination of the activation request, to the closed-side DNS server 14 (sequence Sq1). Specifically, the wireless station 41 sets its own IP address as the source IP address and the IP address of the closed-side DNS server 14 as the destination IP address, and generates and transmits the name resolution request including the domain name of the closed-side activation server 15. It is assumed that the wireless station 41 already holds the IP address of the closed-side DNS server 14. The name resolution request transmitted from the wireless station 41 reaches the closed-side DNS server 14 via the base station 31, the closed network 10, and the router 16.

[0050] When the closed-side DNS server 14 receives the name resolution request including the domain name of the closed-side activation server 15, it transmits a name resolution response including the address of the closed-side activation server 15 to the wireless station 41 (sequence Sq2). In detail, the closed-side DNS server 14 sets its own IP address as the source IP address and the source IP address of the name resolution request as the destination IP address, and generates and transmits the name resolution response including the address of the closed-side activation server 15. The name resolution response transmitted from the closed-side activation server 15 reaches the wireless station 41 via the router 16, the closed network 10, and the base station 31.

[0051] Upon receiving the name resolution response, the wireless station 41 transmits an activation request to the closed-side activation server 15 (sequence Sq3). Specifically, the wireless station 41 generates and transmits an activation request by setting its own IP address as the source IP address and the address of the closed-side activation server 15 included in the name resolution response as the destination IP address. The activation request transmitted from the wireless station 41 reaches the closed-side activation server 15 via the base station 31, the closed network 10, and the router 16.

[0052] Upon receiving the activation request, the closed-side activation server 15 transmits an activation response including the token to the wireless station 41 (sequence Sq4). Specifically, the closed-side activation server 15 sets its own IP address as the source IP address and the source IP address of the activation request, i.e., the IP address of the wireless station 41, as the destination IP address, and generates and transmits the activation response including the token. The activation response transmitted from the closed-side activation server 15 reaches the wireless station 41 via the router 16, the closed network 10, and the base station 31.

[0053] Upon receiving the activation response, the wireless station 41 extracts the token from the activation response and transmits an authentication request including the unique information of the wireless station 41 and the token to the closed-side activation server 15 (sequence Sq5). Specifically, the wireless station 41 sets its own IP address as the source IP address and the address of the closed-side activation server 15 as the destination IP address, generates and transmits an authentication request including the unique information of the wireless station 41 and the token included in the activation response.

[0054] Upon receiving the authentication request, the closed-side activation server 15 performs a parameter check based on the unique information and token of the wireless station 41 included in the authentication request to determine whether the authentication request is valid (sequence Sq6). If the closed-side activation server 15 determines that the authentication request is valid, it registers activation information including the unique information of the wireless station 41 in the storage device 17, 27 (sequence Sq7). After completing the registration of the activation information, the closed-side activation server 15 transmits an authentication response (sequence Sq8). Specifically, the closed-side activation server 15 sets its own IP address as the source IP address and the source IP address of the authentication request, i.e., the IP address of the wireless station 41, as the destination IP address, and generates and transmits the authentication response.

[0055] For example, if neither storage device 17 nor 27 can be accessed and the registration of activation information is not completed successfully, the closed-side activation server 15 will not send the authentication response of sequence Sq8, but will instead send an error notification, for example, a notification that activation has been canceled, to the wireless station 41.

[0056] As shown in FIG. 3, when the activation process does not end normally (step S12; No), for example, when the wireless station 41 receives an error notification from the closed-side activation server 15, the wireless station 41 displays on the screen that an error has occurred (step S20).

[0057] When the activation process is completed successfully (step S12; Yes), specifically, when the wireless station 41 receives an authentication response from the closed-side activation server 15, the wireless station 41 performs a provisioning process to obtain connection information (step S13).

[0058] 5 shows details of the provisioning process performed by the wireless station 41. The wireless station 41 transmits a name resolution request including the domain name of the dedicated connection device 26 that is the destination of the provisioning request to the closed-area DNS server 14 (sequence Sq11).

[0059] When the closed-side DNS server 14 receives the name resolution request including the domain name of the dedicated connection device 26, it transmits a name resolution response including the address of the dedicated connection device 26 to the wireless station 41 (sequence Sq12).

[0060] When the wireless station 41 receives the name resolution response, it transmits a provisioning request including the unique information of the wireless station 41 to the dedicated connection device 26 (sequence Sq13). In detail, the wireless station 41 sets its own IP address as the source IP address and the address of the dedicated connection device 26 included in the name resolution response as the destination IP address, and generates and transmits the provisioning request including the unique information of the wireless station 41.

[0061] Upon receiving the provisioning request, the dedicated connection device 26 transfers the provisioning request to the cloud-side provisioning server 23 (sequence Sq14). The provisioning request transmitted from the wireless station 41 reaches the cloud-side provisioning server 23 via the base station 31, the closed network 10, and the dedicated connection device 26.

[0062] Upon receiving the provisioning request, the cloud-side provisioning server 23 extracts the unique information of the wireless station 41 included in the provisioning request and transmits an activation information request to the storage device 27 to acquire activation information of the wireless station 41 (sequence Sq15). Upon receiving the activation information request, the storage device 27 transmits the activation information of the wireless station 41 to the cloud-side provisioning server 23 (sequence Sq16).

[0063] The cloud-side provisioning server 23 performs an activation status check based on the activation information acquired in sequence Sq16 to determine whether activation of the wireless station 41 has been performed normally (sequence Sq17). If activation has been performed normally, the cloud-side provisioning server 23 transmits a provisioning response addressed to the wireless station 41 to the dedicated connection device 26, the provisioning response including connection information for connecting to the call control server 12 corresponding to the wireless station 41 (sequence Sq18). In detail, the cloud-side provisioning server 23 sets the IP address of its own device as the source IP address and the source IP address of the provisioning request, i.e., the IP address of the wireless station 41, as the destination IP address, and generates and transmits the provisioning response including the connection information.

[0064] Upon receiving the provisioning response, the dedicated connection device 26 transfers the provisioning response to the destination wireless station 41 (sequence Sq19). The provisioning response transmitted from the cloud-side provisioning server 23 reaches the wireless station 41 via the dedicated connection device 26, the closed network 10, and the base station 31.

[0065] For example, if the cloud-side provisioning server 23 is unable to access the storage device 27 and is unable to acquire activation information, the cloud-side provisioning server 23 does not transmit the provisioning response in sequence Sq19, but instead transmits an error notification addressed to the wireless station 41 to the dedicated connection device 26. Upon receiving the error notification, the dedicated connection device 26 forwards the error notification to the wireless station 41.

[0066] 3, when the provisioning process has not been completed normally (step S14; No), for example, when an error notification is received from the cloud-side provisioning server 23 or when the wireless station 41 is unable to connect to the cloud-side provisioning server 23, the wireless station 41 determines whether or not previous information, which is connection information acquired during the previous startup process, is available (step S15). If previous information is not available (step S15; No), the wireless station 41 displays on the screen a message indicating that an error has occurred (step S20).

[0067] If the provisioning process did not end normally but previous information exists (step S14; No, step S15; Yes), or if the provisioning process ended normally (step S14; Yes), the wireless station 41 reflects the connection information or previous information acquired in step S13 as connection information in its own device (step S16).

[0068] Next, the wireless station 41 performs registration to register its own information with the call control server 12 (step S17). Details of the registration process performed by the wireless station 41 are shown in Fig. 6. The wireless station 41 transmits a name resolution request including the domain name of the closed-side gateway server 13, which is the destination of the registration request, to the closed-side DNS server 14 (sequence Sq21).

[0069] When the closed-side DNS server 14 receives the name resolution request including the domain name of the closed-side gateway server 13, it transmits a name resolution response including the address of the closed-side gateway server 13 to the wireless station 41 (sequence Sq22).

[0070] Upon receiving the name resolution response, the wireless station 41 transmits a registration request to the closed-side gateway server 13 (sequence Sq23). Specifically, the wireless station 41 sets its own IP address as the source IP address and the address of the closed-side gateway server 13 included in the name resolution response as the destination IP address, and generates and transmits a registration request including information unique to the wireless station 41. The registration request transmitted from the wireless station 41 reaches the closed-side gateway server 13 via the base station 31, the closed network 10, and the router 16.

[0071] Upon receiving the registration request, the closed-side gateway server 13 transmits the registration request, including the unique information of the wireless station 41, to the call control server 12 corresponding to the wireless station 41 (sequence Sq24). The closed-side gateway server 13 stores the source address of the registration request and the unique information of the wireless station 41 included in the registration request in association with each other.

[0072] Upon receiving the registration request, call control server 12 transmits a registration response including the unique information of wireless station 41 to closed-area gateway server 13, which is the sender of the registration request (sequence Sq25).

[0073] Upon receiving the registration response, the closed-side gateway server 13 transmits the registration response to the wireless station 41 (sequence Sq26). Specifically, the closed-side gateway server 13 sets the IP address of its own device as the source IP address and sets the IP address associated with the unique information of the wireless station 41 included in the registration response received from the call control server 12 as the destination IP address, and then generates and transmits the registration response. The registration response transmitted from the closed-side gateway server 13 reaches the wireless station 41 via the router 16, the closed network 10, and the base station 31.

[0074] 3, when the registration process is not completed normally (step S18; No), for example, when the wireless station 41 does not receive a registration response from the closed-side gateway server 13 within a certain period of time, the wireless station 41 displays a message on the screen indicating that an error has occurred (step S20). The certain period of time may be determined based on the time required for receiving a registration response after transmitting a registration request under normal circumstances, the length of allowable downtime, etc.

[0075] When the registration process is completed normally (step S18; Yes), specifically, when the wireless station 41 receives a registration response from the closed-side gateway server 13, the wireless station 41 displays on its screen a message indicating that the startup process has been completed normally (step S19). When the process of displaying on its screen the message indicating that the startup process has been completed normally in step S19 is completed, the wireless station 41 becomes able to start voice communication. When steps S19 and S20 are completed, the wireless station 41 ends the startup process.

[0076] The startup process of the wireless station 42 is similar to that shown in Fig. 3. The activation, provisioning, and registration processes performed by the wireless station 42 will be described in detail below.

[0077] 7 shows details of the activation process performed by the wireless station 42. The wireless station 42 sends a name resolution request including the domain name of the endpoint device 25, which is the destination of the activation request, to an Internet DNS server on the Internet network 20 (not shown in FIG. 1) (sequence Sq31). Upon receiving the name resolution request including the domain name of the endpoint device 25, the Internet DNS server sends a name resolution response including the address of the endpoint device 25 to the wireless station 42 (sequence Sq32).

[0078] Upon receiving the name resolution response, the wireless station 42 transmits an activation request to the endpoint device 25 (sequence Sq33). Specifically, the wireless station 42 sets the IP address of its own device as the source IP address and the address of the endpoint device 25 included in the name resolution response as the destination IP address, and then generates and transmits the activation request.

[0079] Upon receiving the activation request, endpoint device 25 forwards the activation request to cloud-side activation server 24 (sequence Sq34). The activation request transmitted from wireless station 42 reaches cloud-side activation server 24 via WLAN device 32, Internet network 20, and endpoint device 25.

[0080] Upon receiving the activation request, the cloud-side activation server 24 transmits an activation response addressed to the wireless station 42 and including the token to the endpoint device 25 (sequence Sq35). Specifically, the cloud-side activation server 24 sets the IP address of its own device as the source IP address and sets the source IP address of the activation request, i.e., the IP address of the wireless station 42, as the destination IP address, and generates and transmits the activation response including the token.

[0081] Upon receiving the activation response, endpoint device 25 forwards the activation response to the destination wireless station 42 (sequence Sq36). The activation response sent from cloud-side activation server 24 reaches wireless station 42 via endpoint device 25, Internet network 20, and WLAN device 32.

[0082] When the wireless station 42 receives the activation response, it extracts the token included in the activation response and transmits an authentication request including the unique information of the wireless station 42 and the token to the endpoint device 25 (sequence Sq37). In detail, the wireless station 42 sets its own IP address as the source IP address and the address of the endpoint device 25 as the destination IP address, and generates and transmits the authentication request including the unique information of the wireless station 42 and the token included in the activation response.

[0083] Upon receiving the authentication request, the endpoint device 25 transfers the authentication request to the cloud-side activation server 24 (sequence Sq38).

[0084] Upon receiving the authentication request, the cloud-side activation server 24 performs a parameter check based on the unique information and token of the wireless station 42 included in the authentication request to determine whether the authentication request is valid (sequence Sq39). If the cloud-side activation server 24 determines that the authentication request is valid, it registers activation information including the unique information of the wireless station 42 in the storage device 17, 27 (sequence Sq40). After completing the registration of the activation information, the cloud-side activation server 24 transmits an authentication response (sequence Sq41). Specifically, the cloud-side activation server 24 sets the IP address of its own device as the source IP address and the source IP address of the authentication request, i.e., the IP address of the wireless station 42, as the destination IP address, and generates and transmits the authentication response.

[0085] Upon receiving the authentication response, the endpoint device 25 transfers the authentication response to the destination wireless station 42 (sequence Sq42).

[0086] Note that, for example, if neither storage device 17 nor 27 can be accessed and the registration of activation information does not end normally, cloud-side activation server 24 does not send the authentication response of sequence Sq41, but instead sends an error notification, for example, a notification that activation has been canceled, to endpoint device 25. Upon receiving the error notification, endpoint device 25 forwards the error notification to wireless station 42, which is the destination.

[0087] 8 shows details of the provisioning process performed by the wireless station 42. The wireless station 42 transmits a name resolution request including the domain name of the endpoint device 25 that is the destination of the provisioning request to the Internet DNS server (sequence Sq51).

[0088] When the Internet DNS server receives the name resolution request including the domain name of the endpoint device 25, it transmits a name resolution response including the address of the endpoint device 25 to the wireless station 42 (sequence Sq52).

[0089] Upon receiving the name resolution response, the wireless station 42 transmits a provisioning request including the unique information of the wireless station 42 to the endpoint device 25 (sequence Sq53). In detail, the wireless station 42 sets its own IP address as the source IP address and the address of the endpoint device 25 included in the name resolution response as the destination IP address, and generates and transmits the provisioning request including the unique information of the wireless station 42.

[0090] Upon receiving the provisioning request, the endpoint device 25 transfers the provisioning request to the cloud-side provisioning server 23 (sequence Sq54). The provisioning request transmitted from the wireless station 42 reaches the cloud-side provisioning server 23 via the WLAN device 32, the Internet network 20, and the endpoint device 25.

[0091] Upon receiving the provisioning request, the cloud-side provisioning server 23 extracts the unique information of the wireless station 42 included in the provisioning request and transmits an activation information request to the storage device 27 to acquire activation information of the wireless station 42 (sequence Sq55). Upon receiving the activation information request, the storage device 27 transmits the activation information of the wireless station 42 to the cloud-side provisioning server 23 (sequence Sq56).

[0092] The cloud-side provisioning server 23 performs an activation status check based on the activation information acquired in sequence Sq56 to determine whether activation of the wireless station 42 has been performed normally (sequence Sq57). If activation has been performed normally, the cloud-side provisioning server 23 transmits a provisioning response addressed to the wireless station 42 to the endpoint device 25, the provisioning response including connection information for connecting to the call control server 12 corresponding to the wireless station 42 (sequence Sq58). In detail, the cloud-side provisioning server 23 sets the IP address of its own device as the source IP address and the source IP address of the provisioning request, i.e., the IP address of the wireless station 42, as the destination IP address, generates and transmits the provisioning response including the connection information.

[0093] Upon receiving the provisioning response, the endpoint device 25 transfers the provisioning response to the destination wireless station 42 (sequence Sq59). The provisioning response transmitted from the cloud-side provisioning server 23 reaches the wireless station 42 via the endpoint device 25, the Internet network 20, and the WLAN device 32.

[0094] For example, if the cloud-side provisioning server 23 is unable to access the storage device 27 and is unable to acquire the activation information, the cloud-side provisioning server 23 does not transmit the provisioning response in sequence Sq58, but instead transmits an error notification to the endpoint device 25. Upon receiving the error notification, the endpoint device 25 forwards the error notification to the wireless station 42.

[0095] 9 shows the details of the registration process performed by the wireless station 42. The wireless station 42 sends a name resolution request including the domain name of the endpoint device 25, which is the destination of the registration request, to the Internet DNS server (sequence Sq61). Upon receiving the name resolution request including the domain name of the endpoint device 25, the Internet DNS server sends a name resolution response including the address of the endpoint device 25 to the wireless station 42 (sequence Sq62).

[0096] Upon receiving the name resolution response, the wireless station 42 transmits a registration request to the endpoint device 25 (sequence Sq63). Specifically, the wireless station 42 sets its own IP address as the source IP address and the address of the endpoint device 25 included in the name resolution response as the destination IP address, and generates and transmits the registration request including the unique information of the wireless station 42.

[0097] Upon receiving the registration request, the endpoint device 25 forwards the registration request to the cloud-side gateway server 22 (sequence Sq64). The registration request transmitted from the wireless station 42 reaches the cloud-side gateway server 22 via the WLAN device 32, the Internet network 20, and the endpoint device 25.

[0098] Upon receiving the registration request, the cloud-side gateway server 22 transmits the registration request, including the unique information of the wireless station 42, to the dedicated connection device 26. The registration request is addressed to the call control server 12 corresponding to the wireless station 42 (sequence Sq65). The cloud-side gateway server 22 stores the source address of the registration request and the unique information of the wireless station 42 included in the registration request in association with each other.

[0099] Upon receiving the registration request, the dedicated connection device 26 transfers the registration request to the call control server 12 (sequence Sq66). The registration request sent from the cloud-side gateway server 22 reaches the call control server 12 via the dedicated connection device 26 and the router 16.

[0100] Upon receiving the registration request, the call control server 12 transmits a registration response, including the unique information of the wireless station 42, addressed to the cloud-side gateway server 22 that is the sender of the registration request to the dedicated connection device 26 (sequence Sq67).

[0101] Upon receiving the registration response, the dedicated connection device 26 transfers the registration response to the cloud-side gateway server 22 (sequence Sq68). The registration response sent from the call control server 12 reaches the cloud-side gateway server 22 via the router 16 and the dedicated connection device 26.

[0102] Upon receiving the registration response, the cloud-side gateway server 22 transmits the registration response addressed to the wireless station 42 to the endpoint device 25 (sequence Sq69). In detail, the cloud-side gateway server 22 sets the IP address of its own device as the source IP address and sets the IP address associated with the unique information of the wireless station 42 included in the registration response received from the call control server 12 as the destination IP address, and then generates and transmits the registration response.

[0103] Upon receiving the registration response, endpoint device 25 forwards the registration response to the destination wireless station 42 (sequence Sq70). The registration response sent from cloud-side gateway server 22 reaches wireless station 42 via endpoint device 25, Internet network 20, and WLAN device 32.

[0104] When the startup processing of the wireless stations 41 and 42 is completed as described above, voice communication becomes possible between the wireless stations 41 and 42. As an example, Fig. 10 shows an example in which the wireless station 41 requests a call with the wireless station 42. The wireless station 41 sends a call request to the closed-side gateway server 13, with the wireless station 42 as the destination, specifically, a call request including the ID of the wireless station 42 as the destination ID (sequence Sq71). Upon receiving the call request, the closed-side gateway server 13 transmits the call request to the call control server 12 (sequence Sq72).

[0105] The call control server 12 maintains a correspondence between the callee ID and the closed-side gateway server 13 or the cloud-side gateway server 22. Because the called wireless station 42 is connected to the Internet network 20, the wireless station 42 is associated with the cloud-side gateway server 22. Therefore, upon receiving the above-mentioned call request, the call control server 12 transmits a call request addressed to the cloud-side gateway server 22 corresponding to the called wireless station 42 to the dedicated connection device 26 (sequence Sq73). The call request reaches the dedicated connection device 26 from the call control server 12 via the router 16. Upon receiving the call request, the dedicated connection device 26 forwards the call request to the cloud-side gateway server 22, which is the destination (sequence Sq74).

[0106] When cloud-side gateway server 22 receives the call request, it transmits the call request addressed to wireless station 42, which is the call destination, to endpoint device 25 (sequence Sq75). When endpoint device 25 receives the call request, it transfers the call request to wireless station 42, which is the destination (sequence Sq76).

[0107] Upon receiving the call request, the wireless station 42 generates a call response addressed to the wireless station 41 that sent the call request and transmits the call response to the endpoint device 25 (sequence Sq77). Upon receiving the call response, the endpoint device 25 transfers the call response to the cloud-side gateway server 22 (sequence Sq78). Upon receiving the call response addressed to the wireless station 41, the cloud-side gateway server 22 transmits the call response addressed to the call control server 12 associated with the wireless station 41 to the dedicated connection device 26 (sequence Sq79). Upon receiving the call response, the dedicated connection device 26 transfers the call response to the call control server 12 that is the destination (sequence Sq80).

[0108] When the call control server 12 receives the call response, it transmits the call response to the closed-side gateway server 13 associated with the destination wireless station 41 (sequence Sq81). When the closed-side gateway server 13 receives the call response, it transmits the call response to the destination wireless station 41 (sequence Sq82). Establishing the call session as described above enables voice communication between the wireless stations 41 and 42. Voice data transfer is also performed in the same manner as in FIG. 10 .

[0109] As described above, in the wireless communication system 1 according to the first embodiment, the closed-side DNS server 14 performs name resolution, the closed-side gateway server 13 transmits a registration request or voice data to the call control server 12 associated with the wireless station 41, and the cloud-side gateway server 22 transmits the registration request or voice data to the call control server 12 associated with the wireless station 42. As a result, communication between the wireless station 41 connected to the closed network 10 and the wireless station 42 connected to the Internet network 20 becomes possible.

[0110] When the wireless station 41 is connected to the Internet network 20, it operates in the same manner as the wireless station 42 described above. When the wireless station 42 is connected to the closed network 10, it operates in the same manner as the wireless station 41 described above. As a result, the wireless stations 41 and 42 can connect to the call control server 12 and can perform voice communications with other wireless stations, regardless of whether they are connected to the closed network 10 or the Internet network 20. In other words, the call control server 12 controls the voice communications of the associated wireless stations 41 and 42, regardless of whether they are connected to the closed network 10 or the Internet network 20.

[0111] The wireless communication system 1 according to the first embodiment can be modified in various ways in addition to those described above. First, the configuration of the closed system 11 is not limited to the example described above. As an example, as shown in Fig. 11 , the closed system 11 further includes a closed-side provisioning server 18 that supplies connection information to a wireless station 43 that connects only to the closed network 10. In the example of Fig. 11 , wireless stations 41 and 42 that can connect to the closed network 10 and the Internet 20 are referred to as first wireless stations 41 and 42, and a wireless station 43 that can connect only to the closed network 10 is referred to as a second wireless station 43.

[0112] The closed-side provisioning server 18 holds connection information for the second wireless station 43 to connect to the call control server 12 corresponding to the second wireless station 43. The second wireless station 43 is assumed to hold in advance the IP address of the closed-side provisioning server 18. When started up, the second wireless station 43 transmits a provisioning request to the closed-side provisioning server 18, receives a provisioning response including the address of the call control server 12 from the closed-side provisioning server 18, and reflects the setting information. This enables the second wireless station 43 to connect to the call control server 12 via the base station 31 and the closed network 10, and enables voice communication with the wireless stations 41 and 42.

[0113] Second, the closed system 11 may have any number of closed-side devices. Furthermore, the processing of each closed-side device may be distributed. As an example, the closed system 11 may have multiple closed-side gateway servers 13, and the processing performed by the closed-side gateway server 13 during registration may be load-distributed among the multiple closed-side gateway servers 13. The cloud system 21 may have any number of cloud-side devices. Furthermore, the processing of the cloud-side devices may be load-distributed. As an example, the cloud system 21 may have multiple cloud-side gateway servers 22, and the processing performed by the cloud-side gateway server 22 during registration may be load-distributed among the multiple cloud-side gateway servers 22.

[0114] Third, the closed-side activation server 15 may register activation information only in the master DB storage device 27. In this case, data may be periodically updated from the master DB storage device 27 to the replica DB storage device 17.

[0115] 12 , a wireless communication system 2 according to the second embodiment includes a closed system 11 a provided in a closed network 10 a, a closed system 11 b provided in a closed network 10 b, and a cloud system 21.

[0116] The configurations of the closed systems 11a and 11b are similar to that of the closed system 11 included in the wireless communication system 1 according to embodiment 1. Specifically, the closed system 11a includes a call control server 12a, a closed-side gateway server 13a, a closed-side DNS server 14a, a closed-side activation server 15a, a router 16a, and a storage device 17a. The closed system 11b includes a call control server 12b, a closed-side gateway server 13b, a closed-side DNS server 14b, a closed-side activation server 15b, a router 16b, and a storage device 17b.

[0117] The cloud system 21 has a configuration different from that of the cloud system 21 provided in the wireless communication system 1 according to the first embodiment, and includes dedicated connection devices 26a and 26b corresponding to the closed systems 11a and 11b, respectively. Specifically, the dedicated connection device 26a connects each of the cloud-side devices included in the cloud system 21 to the closed-side devices included in the closed system 11a and the closed network 10a via dedicated lines. The dedicated connection device 26b connects each of the cloud-side devices included in the cloud system 21 to the closed-side devices included in the closed system 11b and the closed network 10b via dedicated lines.

[0118] The wireless stations 41a, 41b, and 42 can perform voice communication with each other via the wireless communication system 2. The startup processing performed by the wireless stations 41a, 41b, and 42 is the same as that in the first embodiment. The wireless stations 41a and 41b are associated with the closed systems 11a and 11b, respectively. When the wireless station 41a cannot connect to the call control server 12a included in the closed system 11a, it connects to the call control server 12b included in the closed system 11b via the cloud system 21. Similarly, when the wireless station 41b cannot connect to the call control server 12b included in the closed system 11b, it connects to the call control server 12a included in the closed system 11a via the cloud system 21. The wireless station 42 preferentially connects to either the call control server 12a in the closed system 11a or the call control server 12b in the closed system 11b, and when it cannot connect to either the call control server 12a or the call control server 12b, it connects to the other of the call control servers 12a and 12b.

[0119] In detail, the wireless station 41a performs the activation process shown in Fig. 4 with the closed-side activation server 15a, performs the provisioning process shown in Fig. 5 with the cloud-side provisioning server 23, and performs the registration process shown in Fig. 6 with the call control server 12a via the closed-side gateway server 13a. When performing each of the activation, provisioning, and registration processes, the wireless station 41a requests name resolution from the closed-side DNS server 14a.

[0120] If the wireless station 41a does not receive a registration response from the closed-side gateway server 13a within a certain period of time during the registration process shown in Fig. 6, the wireless station 41a displays an error on its screen. The wireless station 41a then performs registration processing with the call control server 12b, as shown in Fig. 13. The wireless station 41a transmits a name resolution request including the domain name of the closed-side gateway server 13b, which is the destination of the registration request, to the closed-side DNS server 14a (sequence Sq91).

[0121] When the closed-side DNS server 14a receives the name resolution request including the domain name of the closed-side gateway server 13b, it transmits a name resolution response including the address of the dedicated connection device 26a to the wireless station 41 (sequence Sq92).

[0122] Upon receiving the name resolution response, the wireless station 41a transmits a registration request to the dedicated connection device 26a (sequence Sq93). Specifically, the wireless station 41a generates and transmits a registration request by setting its own IP address as the source IP address and the address of the dedicated connection device 26a included in the name resolution response as the destination IP address, and including the unique information of the wireless station 41a.

[0123] Upon receiving the registration request, dedicated connection device 26a transfers the registration request to dedicated connection device 26b (sequence Sq94). Upon receiving the registration request, dedicated connection device 26b transfers the registration request to closed-area gateway server 13b (sequence Sq95).

[0124] Upon receiving the registration request, the closed-side gateway server 13b transmits the registration request including the unique information of the wireless station 41a to the call control server 12b (sequence Sq96). The closed-side gateway server 13b stores the source address of the registration request and the unique information of the wireless station 41a included in the registration request in association with each other.

[0125] Upon receiving the registration request, the call control server 12b transmits a registration response including the unique information of the wireless station 41a to the closed-area gateway server 13b that has sent the registration request (sequence Sq97).

[0126] Upon receiving the registration response, the closed-side gateway server 13b transmits the registration response to the dedicated connection device 26b (sequence Sq98). Specifically, the closed-side gateway server 13b sets the IP address of its own device as the source IP address and sets the IP address associated with the unique information of the wireless station 41a included in the registration response received from the call control server 12b as the destination IP address, and then generates and transmits the registration response.

[0127] Upon receiving the registration response, the dedicated connection device 26b transfers the registration response to the dedicated connection device 26a (sequence Sq99). Upon receiving the registration response, the dedicated connection device 26a transfers the registration response to the wireless station 41a (sequence Sq100).

[0128] As described above, when the radio station 41a is unable to perform the registration process with the call control server 12a, the radio station 41a can connect to the call control server 12b and establish voice communication by performing the registration process with the call control server 12b.

[0129] The same is true for the wireless station 41b. In detail, the wireless station 41b performs the activation process shown in Fig. 4 with the closed-side activation server 15b, the provisioning process shown in Fig. 5 with the cloud-side provisioning server 23, and the registration process shown in Fig. 6 with the call control server 12b via the closed-side gateway server 13b. When performing each of the activation, provisioning, and registration processes, the wireless station 41b requests name resolution from the closed-side DNS server 14b.

[0130] If the wireless station 41b does not receive a registration response from the closed-area gateway server 13b within a certain period of time during the registration process shown in Fig. 6, the wireless station 41b displays an error on its screen. The wireless station 41b then performs registration processing with the call control server 12a, as shown in Fig. 13. As a result, the wireless station 41b is able to connect to the call control server 12a and establish voice communication.

[0131] 9 with the call control server 12a, if the wireless station 42 does not receive a registration response from the closed-area gateway server 13a within a certain period of time, the wireless station 42 displays an error on the screen. The wireless station 42 then performs the registration process shown in FIG. 9 with the call control server 12b. By performing the registration process, the wireless station 42 can connect to the call control server 12b and establish voice communication.

[0132] As described above, according to the wireless communication system 2 according to the second embodiment, when connection to one of the call control servers 12a and 12b is unavailable, voice communication can be performed by connecting to the other call control server 12a and 12b. In other words, when one of the call control servers 12a and 12b is unable to control communication between the wireless stations 41a, 41b, and 42, the other of the call control servers 12a and 12b controls communication between the wireless stations 41a, 41b, and 42. Therefore, the availability of the wireless communication system 2 is higher than that of the wireless communication system 1 according to the first embodiment.

[0133] The wireless communication system 2 according to the second embodiment can be modified in various ways other than those described above. The number of closed systems is not limited to the above example, and may be any natural number equal to or greater than two.

[0134] The modifications described in the first embodiment can also be applied to the second embodiment. Specifically, each of the closed systems 11a and 11b may further include a closed-side provisioning server 18.

[0135] The closed systems 11a and 11b may each have any number of closed-side devices, and the cloud system 21 may each have any number of cloud-side devices.

[0136] An example of a hardware configuration for realizing the above-described wireless communication systems 1 and 2 is shown in Fig. 14. The closed-side devices included in the closed systems 11, 11a, and 11b and the cloud-side devices included in the cloud system 21 are realized by a processor 61, a memory 62, and an interface 63. The processor 61, the memory 62, and the interface 63 are connected to one another by a bus 60. The processor 61 includes any electronic circuit including a transistor, and is considered to be a circuit or a processor circuit.

[0137] For example, the functions of the closed-side devices of the closed systems 11, 11a, and 11b and the cloud-side devices of the cloud system 21 are realized by software, firmware, which is software embedded in electronic devices, or a combination of software and firmware. The software is written as a program and stored in the memory 62. The processor 61 executes the program stored in the memory 62 to realize the functions of the above-mentioned parts. That is, the memory 62 stores programs for executing the processes of the closed-side devices of the closed systems 11, 11a, and 11b and the cloud-side devices of the cloud system 21.

[0138] The memory 62 includes, for example, non-volatile or volatile semiconductor memory such as RAM (Random Access Memory), ROM (Read-Only Memory), flash memory, EPROM (Erasable Programmable Read Only Memory), EEPROM (Electrically Erasable and Programmable Read-Only Memory), magnetic disk, flexible disk, optical disk, compact disk, mini disk, DVD (Digital Versatile Disc), etc.

[0139] For example, the interface 63 connects the closed systems 11, 11a, and 11b to the cloud system 21 or the wireless stations 41, 41a, and 41b, and connects the cloud system 21 to the wireless station 42, thereby establishing voice communication. The interface 63 has multiple types of interface modules as necessary.

[0140] 14 illustrates one processor 61 and one memory 62, the closed-side devices of the closed systems 11, 11a, and 11b and the cloud-side devices of the cloud system 21 may be realized by a plurality of processors 61 and a plurality of memories 62. In this case, the plurality of processors 61 and the plurality of memories 62 may cooperate with each other to execute the functions of the devices of the closed systems 11, 11a, and 11b and the cloud system 21.

[0141] Each device of the closed systems 11, 11a, and 11b and the cloud system 21 may be realized by a processing circuit 71, as shown in Fig. 15. The processing circuit 71 is connected to other devices via an interface circuit 72.

[0142] When the processing circuitry 71 is dedicated hardware, the processing circuitry 71 includes, for example, a single circuit, a composite circuit, a processor, an ASIC (Application Specific Integrated Circuit), an FPGA (Field Programmable Gate Array), or a combination thereof. The closed-side devices of the closed systems 11, 11a, and 11b and the cloud-side devices of the cloud system 21 may be realized by any number of processing circuits 71.

[0143] Some of the functions of the closed-side devices of the closed systems 11, 11a, and 11b and the cloud-side devices of the cloud system 21 may be realized by dedicated hardware, and other functions may be realized by software or firmware. For example, in the closed system 11, the call control server 12, the closed-side gateway server 13, the closed-side DNS server 14, and the closed-side activation server 15 may be realized by the processor 61 shown in Fig. 14 reading and executing programs stored in the memory 62, and the router 16 and the storage device 17 may be realized by the processing circuit 71 shown in Fig. 15.

[0144] Furthermore, the above-described hardware configuration and flowchart are merely examples and can be changed and modified as desired.

[0145] The present invention allows various embodiments and modifications without departing from the broad spirit and scope of the present invention. Furthermore, the above-described embodiments are intended to explain the present invention and do not limit the scope of the present invention. That is, the scope of the present invention is defined by the claims, not the embodiments. Various modifications made within the scope of the claims and the meaning of the invention equivalent thereto are considered to be within the scope of the present invention.

[0146] This application is based on Japanese Patent Application No. 2024-118865, filed on July 24, 2024. The entire specification, claims, and drawings of Japanese Patent Application No. 2024-118865 are incorporated herein by reference.

[0147] 1, 2 Wireless communication system 10, 10a, 10b Closed network 11, 11a, 11b Closed system 12, 12a, 12b Call control server 13, 13a, 13b Closed side gateway server 14, 14a, 14b Closed side DNS server 15, 15a, 15b Closed side activation server 16, 16a, 16b Router 17, 17a, 17b, 27 Storage device 18 Closed side provisioning server 20 Internet network 21 Cloud system 22 Cloud side gateway server 23 Cloud side provisioning server 24 Cloud side activation server 25 Endpoint device 26, 26a, 26b Dedicated connection device 31 Base station 32 WLAN device 41, 42 Wireless station (first wireless station) 41a, 41b Wireless station 43 Wireless station (second wireless station) 51 LTE communication circuit 52 WLAN communication circuit 53 Communication control circuit 54 Data processing circuit 55 Input circuit 56 Output circuit 60 Bus 61 Processor 62 Memory 63 Interface 71 Processing circuit 72 Interface circuit

Claims

1. A wireless communication system comprising a closed system provided in a closed network and a cloud system provided in an Internet network, said closed system and said cloud system being connected to each other so as to be able to communicate with each other, said closed system comprising: a call control server that controls communication between a plurality of wireless stations, each of which is connected to either said closed network or said Internet network; a closed-side gateway server that maintains correspondence between said wireless stations and said call control server, and that, upon receiving a registration request or voice data from a wireless station connected to said closed network, transmits said registration request or said voice data to said call control server associated with said wireless station, and, upon receiving a registration response or voice data from said call control server, transmits said registration response or said voice data to said wireless station as a destination; and a closed-side DNS server that, upon receiving a name resolution request for a domain name of a closed-side device included in said closed system or a cloud-side device included in said cloud system from said wireless station connected to said closed network, performs name resolution of the domain name included in the name resolution request, and transmits a name resolution response including an address corresponding to said domain name to said wireless station, and said cloud system comprises: a cloud-side gateway server that maintains correspondence between the wireless stations and the call control servers, and that, upon receiving a registration request or voice data from the wireless station connected to the Internet network, transmits the registration request or the voice data to the call control server that is associated with the wireless station, and, upon receiving a registration response or voice data addressed to the wireless station connected to the Internet network from the call control server, transmits the registration response or the voice data to the wireless station.

2. The wireless communication system according to claim 1, wherein when the closed-side DNS server receives the name resolution request of the closed-side gateway server, which is the closed-side device, from the wireless station connected to the closed network, it transmits the name resolution response including the address of the closed-side gateway server to the wireless station.

3. The wireless communication system according to claim 1 or 2, wherein the closed system further comprises a closed-side activation server that, when it receives an activation request from a wireless station connected to the closed network as the closed-side device, registers activation information including information that uniquely identifies the wireless station in a storage device provided in each of the closed system and the cloud system.

4. The wireless communication system described in claim 3, wherein when the closed-side DNS server receives the name resolution request of the closed-side activation server, which is the closed-side device, from the wireless station connected to the closed network, it transmits the name resolution response including the address of the closed-side activation server to the wireless station.

5. A wireless communication system according to any one of claims 1 to 4, wherein the cloud system further comprises a cloud-side activation server that, when it receives an activation request from a wireless station connected to the Internet network as the cloud-side device, the activation information including the unique information that uniquely identifies the wireless station, registers the activation information including the unique information in a storage device provided in each of the closed system and the cloud system.

6. The wireless communication system according to any one of claims 1 to 5, wherein the cloud system further comprises a cloud-side provisioning server as the cloud-side device, which, upon receiving a provisioning request from a wireless station connected to the closed network, transmits a provisioning response including the domain name of the closed-network gateway server to the wireless station, and which, upon receiving a provisioning request from a wireless station connected to the Internet network, transmits a provisioning response including the domain name of the cloud-side gateway server to the wireless station.

7. The wireless communication system described in claim 6, wherein the cloud system further has dedicated connection devices that connect each of the cloud side devices to the closed side devices and the closed network by dedicated lines, the dedicated connection devices forward data received from the wireless stations or the closed side devices connected to the closed network to the cloud side devices according to the type of data, and when the closed side DNS server receives the name resolution request for the domain name of the cloud side provisioning server from the wireless station, it transmits the name resolution response including the address of the dedicated connection device to the wireless station.

8. A wireless communication system according to any one of claims 1 to 7, wherein the cloud system further comprises dedicated connection devices that connect each of the cloud side devices to the closed side devices and the closed network by dedicated lines, and the dedicated connection devices transfer data received from the wireless stations or the closed side devices connected to the closed network to the cloud side devices according to the type of data.

9. The wireless communication system according to any one of claims 1 to 8, wherein the cloud system further comprises an endpoint device that connects each of the cloud-side devices to the Internet network, and an Internet DNS server provided on the Internet network, when receiving a name resolution request for the cloud-side device from the wireless station connected to the Internet network, transmits a name resolution response including the address of the endpoint device to the wireless station, and the endpoint device transfers data received from the wireless station connected to the Internet network to the cloud-side device according to the type of data.

10. A wireless communication system according to any one of claims 1 to 9, wherein the call control server controls communication between at least one first wireless station that can be connected to both the closed network and the Internet network and at least one second wireless station that can be connected only to the closed network, and the closed system further comprises a closed-side provisioning server that, upon receiving a provisioning request from the second wireless station connected to the closed network, transmits a provisioning response to the second wireless station that includes the address of the call control server.

11. A wireless communication system according to any one of claims 1 to 10, wherein the call control server controls the communication of the associated wireless station regardless of whether the wireless station is connected to the closed network or the Internet network.

12. A wireless communication system according to any one of claims 1 to 11, comprising a plurality of closed systems connected to each other so as to be able to communicate with each other via the cloud system, wherein when the call control server of one of the closed systems becomes unable to control communications between the plurality of wireless stations, the call control server of another of the closed systems controls communications between the plurality of wireless stations.

13. A wireless communication system comprising a closed system provided in a closed network and a cloud system provided in an Internet network, said closed system and said cloud system being connected to each other so as to be able to communicate with each other, said closed system having a call control server that controls communication between a plurality of wireless stations each connected to either said closed network or said Internet network, a closed-side gateway server that maintains correspondence between said wireless stations and said call control servers, and a closed-side DNS server that performs name resolution, said cloud system having a cloud-side gateway server that maintains correspondence between said wireless stations and said call control servers, said method being performed by said wireless communication system, wherein said closed-side gateway server, upon receiving a registration request or voice data from said wireless station connected to said closed network, transmits said registration request or voice data to said call control server that is associated with said wireless station, and upon receiving a registration response or voice data from said call control server, transmits said registration response or voice data to said wireless station that is the destination, and said closed-side DNS server the cloud-side gateway server maintains a correspondence between the wireless station and the call control server, and when a registration request or voice data is received from the wireless station connected to the Internet network, the cloud-side gateway server transmits the registration request or voice data to the call control server associated with the wireless station, and when a registration response or voice data addressed to the wireless station connected to the Internet network is received from the call control server, the cloud-side gateway server transmits the registration response or voice data to the wireless station.

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