Relay system and relay method

Abstract

To provide technology that enables LGWAN-ASP operators to use external services from the LGWAN side. [Solution] One aspect of the present invention is a relay system for making application services located on an external network available from within LGWAN, comprising: a first server that receives service requests for application services in a first segment exposed to the LGWAN side and relays the service requests to a second segment isolated from LGWAN and the external network; a second server that relays the service requests relayed to the second segment to a third segment exposed to the external network side; and a third server that relays the service requests relayed to the third segment to a server providing the application services.

Description

Technical Field

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

Background Art

[0002] LGWAN (Local Government Wide Area Network) is known as an administrative-exclusive closed network that interconnects the intranetworks of local public bodies. Since LGWAN is an administrative-exclusive network, it is configured to ensure security for handling highly confidential information safely. Also, there is LGWAN-ASP (LGWAN Application Service Provider) that provides various administrative services (hereinafter referred to as "ASP services") for local public bodies through LGWAN. Each operator (hereinafter referred to as "LGWAN-ASP operator") that operates LGWAN-ASP has a dedicated system infrastructure (such as a public cloud or an on-premises environment, etc.) for providing ASP services, and constructs ASP services on the dedicated system infrastructure (for example, see Patent Document 1).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] On the other hand, with the spread of cloud services and web services via the internet, local governments have a need to use these external services from the LGWAN side. Traditionally, addressing this need required each LGWAN-ASP provider to individually design network and data transfer methods compliant with the three-tier separation model, which incurred significant costs. Therefore, there is a need for technology that provides LGWAN-ASP providers with an environment that allows them to use external services from the LGWAN side.

[0005] Therefore, the present invention aims to provide technology that enables LGWAN-ASP operators to use external services from the LGWAN side, by providing an environment for such services. [Means for solving the problem]

[0006] One aspect of the present invention is a relay system for making application services existing on an external network of LGWAN (Local Government Wide Area Network), which interconnects the internal networks of local government organizations, available from within LGWAN, comprising: a first server that receives service requests for the application services transmitted from within LGWAN in a first segment, which is a network segment exposed to the LGWAN side, and relays the service requests to a second segment, which is a network segment isolated from LGWAN and the external network; a second server that relays the service requests relayed to the second segment to a third segment, which is a network segment exposed to the external network side; and a third server that relays the service requests relayed to the third segment to an application server that provides the application services.

[0007] One aspect of the present invention is the relay system described above, wherein the first server relays the service request to the second server using a reverse proxy function, the second server relays the service request to the third server using a first forward proxy function, and the third server relays the service request to the application server using a second forward proxy function.

[0008] One aspect of the present invention is the relay system described above, wherein the service request is relayed from the LGWAN side to the application server by encrypted communication, the first server has a first termination function for terminating the encrypted communication of the service request transmitted from within the LGWAN, and a first encrypted communication function for relaying the service request terminated by the first termination function to the second server by encrypted communication, the second server has a second termination function for terminating the encrypted communication of the service request relayed from the first server, and a second encrypted communication function for relaying the service request terminated by the second termination function to the third server by encrypted communication, and the third server has a third termination function for terminating the encrypted communication of the service request relayed from the second server, and a third encrypted communication function for relaying the service request terminated by the third termination function to the application server by encrypted communication.

[0009] One aspect of the present invention is the relay system described above, further comprising an environment setting unit that generates first configuration information relating to the reverse proxy function, second configuration information relating to the first forward proxy function, and third configuration information relating to the second forward proxy function based on design information relating to communication with the application service provided by the LGWAN-ASP operator providing the application service, and applies the first configuration information, the second configuration information, and the third configuration information to the first server, the second server, and the third server, respectively.

[0010] One aspect of the present invention is a relay method for making application services located on an external network of LGWAN (Local Government Wide Area Network), which interconnects the internal networks of local government organizations, available from within LGWAN, comprising: a first step in which a first server receives a service request for the application service transmitted from within LGWAN in a first segment, which is a network segment exposed to the LGWAN side, and relays the service request to a second segment, which is a network segment isolated from LGWAN and the external network; a second step in which a second server relays the service request relayed to the second segment to a third segment, which is a network segment exposed to the external network side; and a third step in which a third server relays the service request relayed to the third segment to an application server that provides the application service. [Effects of the Invention]

[0011] According to the present invention, it is possible to realize a service that provides an environment for LGWAN-ASP operators to use external services from the LGWAN side. [Brief explanation of the drawing]

[0012] [Figure 1] This figure shows an example of the system configuration of the LGWAN relay system 10 of the embodiment. [Figure 2] This figure shows a schematic diagram of the network configuration of the LGWAN relay system 10 in this embodiment. [Figure 3] This diagram illustrates the difference between the conventional connection method and the connection method of this embodiment regarding the connection method between LGWAN and the external network. [Figure 4] This figure shows an example of the environment design in the proxy forwarding method of this embodiment. [Figure 5]This figure shows an example of the functional configuration of the first proxy server 11, the second proxy server 12, and the third proxy server 13 in this embodiment. [Modes for carrying out the invention]

[0013] Embodiments of the present invention will be described below with reference to the drawings.

[0014] Figure 1 shows an example of the system configuration of the LGWAN relay system 10 of the embodiment. The LGWAN relay system 10 is a system that relays communication between a local government system (hereinafter referred to as "local government system") 30 located inside LGWAN 20 and a server (hereinafter referred to as "ASP server") 50 of an LGWAN-ASP service provider configured on an external network such as the Internet 40. Through relaying by the LGWAN relay system 10, it becomes possible to use web services (hereinafter referred to as "ASP services") provided by the ASP server 50 from the local government system 30 inside LGWAN 20.

[0015] The LGWAN relay system 10 and the ASP server 50 can communicate with each other via the Internet 40. The local government system 30 can access the LGWAN relay system 10 via LGWAN 20. By accessing the Internet 40 via the LGWAN relay system 10, the local government system 30 can use the ASP service while meeting the security requirements of LGWAN 20.

[0016] [LGWAN Security Requirements] (1) When bringing files into LGWAN20 from an external network, LGWAN20's security requirements stipulate that the contents of the target files must be sanitized by converting them to text or images. Sanitization here means reconstructing the target file in a clean environment by removing potentially malicious data areas. Examples of sanitization include checking and disabling macros, images, hyperlinks, etc., within the file. Files that require assurance of authenticity through digital signatures, etc., are exempt from sanitization because their authenticity would be compromised by sanitization, and their introduction into LGWAN20 is restricted.

[0017] (2) When it is necessary to access an external network such as the Internet 40 from within LGWAN 20, it is necessary to separate the session so that the access source (e.g., local government system 30) and the access destination (e.g., ASP server 50) do not establish a direct connection through a communication protocol.

[0018] In this embodiment, the LGWAN relay system 10, in order to enable the use of ASP services from within LGWAN 20 while satisfying these security requirements, separates the network between the external network such as the internet and LGWAN 20 into three segments: the LGWAN-side public segment SG1, the gateway segment SG2, and the external network-side public segment SG3.

[0019] FIG. 2 is a diagram showing an outline of the network configuration of the LGWAN relay system 10 of the present embodiment. In order to satisfy the security requirement of (1) above, the LGWAN relay system 10 receives a target file brought into the LGWAN 20 from an external network in the external network-side public segment SG3, and detoxifies the file within the segment. The LGWAN relay system 10 can prevent the target file from being brought into the LGWAN 20 while having a data area where there is a possibility of malice by relaying the detoxified target file to the gateway segment SG2.

[0020] Also, in order to satisfy the security requirement of (2) above, the LGWAN relay system 10 relays the communication session between the external network and the LGWAN 20 while terminating it in each of the segments SG1 to SG3. Thereby, the local government system 30 can use the ASP service provided by the ASP server 50 without establishing a direct communication connection with the ASP server 50.

[0021] Returning to FIG. 1. The ASP server 50 is a server that provides an ASP service to the local government system 30. For example, the ASP server 50 is a server constructed on a public cloud accessible via the Internet 40. The ASP server 50 provides an ASP service. The service request of the local government system 30 for the ASP service is relayed to the Internet 40 side by the LGWAN relay system 10 via the LGWAN 20 and transferred to the ASP service. Also, the response from the ASP service to the service request is relayed to the LGWAN 20 by the LGWAN relay system 10 and transferred to the local government system 30.

[0022] The LGWAN relay system 10 is a system for providing LGWAN-ASP operators with a service (hereinafter referred to as the "LGWAN relay service") that relays communication between LGWAN 20 and the Internet 40 while meeting the security requirements of LGWAN 20. The LGWAN relay service may be provided by the operator of LGWAN 20 or by other operators. Hereinafter, operators providing the LGWAN relay service will be referred to as "relay service providers." By using the LGWAN relay service provided by relay service providers, LGWAN-ASP operators can build and provide ASP services for local governments on an external network.

[0023] The LGWAN relay system 10 includes, for example, a first proxy server 11, a second proxy server 12, a third proxy server 13, and an environment setting unit 14. The first proxy server 11, the second proxy server 12, and the third proxy server 13 may be configured as physical servers or as virtual servers.

[0024] The first proxy server 11 is located in the LGWAN-side public segment SG1 and relays communication between the gateway segment SG2 and LGWAN 20. More specifically, the first proxy server 11 functions as a reverse proxy for the local government system 30.

[0025] The second proxy server 12 is located in gateway segment SG2 and relays communication between the LGWAN-side public segment SG1 and the external network-side public segment SG3. More specifically, the second proxy server 12 functions as a forward proxy with the first proxy server 11 as its client.

[0026] The third proxy server 13 is located in the external network-side public segment SG3 and is a server that relays communication between the external network and the gateway segment SG2. More specifically, the third proxy server 13 functions as a forward proxy with the second proxy server 12 as its client. Hereinafter, the forward proxy by the second proxy server 12 may be referred to as the first forward proxy, and the forward proxy by the third proxy server 13 may be referred to as the second forward proxy to distinguish them. When there are files brought into LGWAN20 from the external network, the third proxy server 13 performs sanitization of the target files and relays the sanitized target files to the second proxy server 12.

[0027] The environment setting unit 14 is a functional unit that performs environment settings for the first proxy server 11, the second proxy server 12, and the third proxy server 13. The environment setting unit 14 may be configured as a separate server from the first proxy server 11, the second proxy server 12, and the third proxy server 13, or it may be configured as part of the first proxy server 11, the second proxy server 12, and the third proxy server 13.

[0028] More specifically, the environment configuration unit 14 obtains configuration information related to environment settings from the relay service provider and configures the first proxy server 11, the second proxy server 12, and the third proxy server 13 based on said configuration information. For example, the relay service provider may conduct interviews with the ASP provider to gather information necessary for the design and generate configuration information based on the results of the interviews. Alternatively, the environment configuration unit 14 may be configured to generate configuration information based on the results of such interviews according to predetermined design rules.

[0029] Figure 3 illustrates the difference between the conventional connection method and the connection method of this embodiment regarding the connection method between LGWAN20 and the external network. Taking the OSI basic reference model as an example, the conventional connection method can be described as a data transfer method that transfers data at a layer lower than the session layer (hereinafter referred to as the "data transfer method"). Therefore, when making ASP services available from LGWAN20, each LGWAN-ASP provider had to implement a three-tier separation network design and data transfer design.

[0030] In contrast, the connection method of this embodiment can be described as a method that relays data using forward proxies and reverse proxies at layers above the session layer (hereinafter referred to as the "proxy forwarding method"). Therefore, with regard to data transfer between LGWA32 and the external network, LGWAN-ASP operators do not need to perform three-layer separation network design or data transfer design. Furthermore, according to the connection method of this embodiment, relay service providers can independently perform environment design related to the proxy forwarding method from LGWAN-ASP operators. Therefore, by pre-defining environment design policies, relay service providers can mechanically perform environment design for proxy forwarding methods for multiple LGWAN-ASP operators. As a result, relay service providers can quickly provide LGWAN relay services to LGWAN-ASP operators.

[0031] Figure 4 shows an example of the environment design in the proxy forwarding method of this embodiment. Figure 4 shows an example of the environment design when the LGWAN side public segment SG1, gateway segment SG2, and external network side public segment SG3 are configured by a common core firewall FW. Note that the core firewall FW is just one example, and the method of configuring each segment is not limited to the configuration shown in Figure 4. For example, the core firewall FW may be divided into multiple switches.

[0032] The first port P1 of the core firewall FW is connected to the LGWAN-side public segment SG1 and can communicate with the first proxy server 11. The second port P2 is connected to the gateway segment SG2 and can communicate with the second proxy server 12. The third port P3 is connected to the external network-side public segment SG3 and can communicate with the third proxy server 13. The fourth port P4 is connected to the internet gateway GW and can access the internet via the internet gateway GW.

[0033] In this case, the relay service provider performs the following environment design and configuration tasks, for example, in order to implement proxy forwarding that relays communication between the ASP server 50 and the local government system 30.

[0034] (1) The LGWAN-ASP provider is asked to provide the network address A1 that the first proxy server 11 uses to receive requests from the LGWAN 20 side to the ASP server 50, and the network address A2 that the ASP server 50 exposes to the internet. If the LGWAN-ASP provider does not specify a network address, the relay service provider may determine the network address A1 and notify the LGWAN-ASP provider.

[0035] (2) From the ports available on the core firewall (FW), determine which ports will be used as the first port P1, the second port P2, the third port P3, and the fourth port P4.

[0036] (3) Determine the network addresses to be assigned to the first port P1, the second port P2, the third port P3, and the fourth port P4.

[0037] (4) Set the network addresses determined in (3) to the first port P1, the second port P2, the third port P3, and the fourth port P4.

[0038] (5) The first proxy server 11 is configured to forward service requests destined for network address A1 to the first port P1, and to forward service responses received from the second port P2 to network address A1.

[0039] (6) Configure the third proxy server 13 to set the network address A2 of the ASP server 50, which will be the destination for service requests relayed from the second port P2.

[0040] (7) Configure forwarding settings between the first port P1 and the second port P2, between the second port P2 and the third port P3, and between the third port P3 and the fourth port P4.

[0041] Note that the example in Figure 4 illustrates a simplified network configuration for ease of understanding, and in reality, network devices not shown (such as switches, routers, and firewalls) may be deployed as needed. In addition to the information described in Figure 4, relay service providers may interview LGWAN-ASP providers to gather any other information necessary depending on the actual network configuration.

[0042] Figure 5 shows an example of the functional configuration of the first proxy server 11, the second proxy server 12, and the third proxy server 13. The first proxy server 11 includes a reverse proxy function 111, a domain translation function 112, an encrypted communication termination function 113, and an encrypted communication function 114. As described above, the reverse proxy function 111 receives service requests from the LGWAN-side public segment SG1 on behalf of the ASP server 50 and relays the received service requests to the gateway segment SG2.

[0043] The domain translation function 112 is a function that translates the destination domain of service requests received from the LGWAN20 side. The domain translation function 112 translates the destination domain published on the LGWAN20 side to the destination domain published on the internet side.

[0044] The encrypted communication termination function 113 is a function that terminates (ends) encrypted communication with the other party. Examples of encrypted communication here include SSL (Secure Socket Layer) communication and TLS (Transport Layer Security) communication. The encrypted communication termination function 113 terminates encrypted communication when a service request from the LGWAN20 side is made using encrypted communication. In other words, the encrypted communication of the service request is decrypted (terminated) by the encrypted communication termination function 113.

[0045] The encrypted communication function 114 is a function for communicating with the other party using encrypted communication. The encrypted communication function 114 enables encrypted communication with the second proxy server 12. The encrypted communication function 114 relays the service request, which has been decrypted by the encrypted communication termination function 113, to the second proxy server 12 using newly encrypted communication.

[0046] The reverse proxy function 111, the domain translation function 112, the encrypted communication termination function 113, and the encrypted communication function 114 can be implemented by combining software such as Apache®, Squid®, and SSL-Bump®.

[0047] The second proxy server 12 includes a first forward proxy function 121, an encrypted communication termination function 122, and an encrypted communication function 123. The first forward proxy function 121 is a forward proxy function for realizing the first forward proxy. The first forward proxy function 121 forwards service requests relayed from the first proxy server 11 to the third proxy server 13. The first forward proxy function 121 can be implemented, for example, by Squid®.

[0048] The encrypted communication termination function 122 is a function that terminates (ends) encrypted communication with the other party. The encrypted communication termination function 122 terminates the encrypted communication from the encrypted communication function 114. In other words, the encrypted communication termination function 122 decrypts (terminates) the encrypted communication of the service request that was encrypted by the encrypted communication function 114.

[0049] The encrypted communication function 123 is a function for communicating with the other party using encrypted communication. The encrypted communication function 123 enables encrypted communication with the third proxy server 13. The encrypted communication function 123 relays the service request, which has been decrypted by the encrypted communication termination function 122, to the third proxy server 13 using newly encrypted communication.

[0050] The first forward proxy function 121, the encrypted communication termination function 122, and the encrypted communication function 123 can be implemented by combining software such as Apache®, Squid®, and SSL-Bump®.

[0051] The third proxy server 13 includes a second forward proxy function 131, a URL filtering function 132, an encrypted communication termination function 133, and an encrypted communication function 134. The second forward proxy function 131 is a forward proxy function for realizing a second forward proxy. The second forward proxy function 131 relays service requests relayed from the second proxy server 12 to the ASP server 50.

[0052] The URL filtering function 132 filters communication from the LGWAN20 side to the external network side based on the URL of the destination. The URL filtering function 132 allows access only to destinations defined in the whitelist, or prohibits access to destinations defined in the blacklist. For example, a relay service provider may register the URL of the ASP server 50 in the whitelist to restrict access from the LGWAN20 side to the external network side to the ASP server 50.

[0053] The encrypted communication termination function 133 is a function that terminates (ends) encrypted communication with the other party. The encrypted communication termination function 133 terminates the encrypted communication from the encrypted communication function 123. In other words, the encrypted communication termination function 133 decrypts (terminates) the encrypted communication of the service request that was encrypted by the encrypted communication function 123.

[0054] The encrypted communication function 134 is a function for communicating with the other party using encrypted communication. The encrypted communication function 134 enables encrypted communication with the ASP server 50. The encrypted communication function 134 relays the service request, which has been decrypted by the encrypted communication termination function 133, to the ASP server 50 using new encrypted communication.

[0055] The third forward proxy function 131, URL filtering function 132, encrypted communication termination function 133, and encrypted communication function 134 can be implemented by combining software such as Apache®, Squid®, and SSL-Bump®.

[0056] Furthermore, all or part of the functions of the first proxy server 11, the second proxy server 12, and the third proxy server 13 may be implemented using hardware such as ASICs (Application Specific Integrated Circuits), PLDs (Programmable Logic Devices), or FPGAs (Field Programmable Gate Arrays). The program may be recorded on a computer-readable recording medium. Computer-readable recording media include, for example, portable media such as flexible disks, magneto-optical disks, ROMs, and CD-ROMs, and storage devices such as hard disks built into computer systems. The program may also be transmitted via telecommunications lines.

[0057] The LGWAN relay system 10 of the embodiment described above can provide LGWAN-ASP operators with an environment that allows them to use external services from the LGWAN 20 side. By realizing such a service, LGWAN-ASP operators can provide ASP services configured on external networks such as the internet to LGWAN 20 more easily and quickly.

[0058] In the above embodiment, the case in which the LGWAN relay system 10 provides LGWAN relay services to one LGWAN-ASP provider was mainly described. However, the LGWAN relay system 10 may be configured to provide LGWAN relay services to multiple LGWAN-ASP providers. For example, an LGWAN relay service provider may provide dedicated LGWAN relay services to multiple LGWAN-ASP providers by building a dedicated environment for each LGWAN-ASP provider in the LGWAN relay system 10. When providing dedicated LGWAN relay services to multiple LGWAN-ASP providers, the relay service provider may completely isolate all hardware resources for each LGWAN-ASP provider, or it may share some hardware resources among the LGWAN-ASP providers. Similarly, for software resources, the relay service provider may completely isolate all software resources for each LGWAN-ASP provider, or it may share some software resources among the LGWAN-ASP providers. Furthermore, when sharing software resources, the relay service provider may configure the software to divide the software resources internally.

[0059] While embodiments of this invention have been described in detail above with reference to the drawings, the specific configuration is not limited to these embodiments and includes designs and the like that do not depart from the spirit of this invention. [Explanation of Symbols]

[0060] 10. LGWAN Relay System 11. First Proxy Server 111 Reverse proxy function 112 Domain Translation Function 113 Encrypted communication termination function 114. Encrypted communication function 12. Second Proxy Server 121 First Forward Proxy Function 122 Encrypted communication termination function 123 Encrypted communication function 13. Third Proxy Server 131 Second Forward Proxy Function 132 URL filtering function 133 Encrypted communication termination function 134 Encrypted communication function 14. Environment Settings Section 30 Local Government Systems 40 Internet 50 ASP Servers

Claims

1. A relay system for making application services located on the external network of an LGWAN (Local Government Wide Area Network), which interconnects the internal networks of local government organizations, available from within the LGWAN, A first server receives service requests for the application service transmitted from within the LGWAN in a first segment, which is a network segment exposed to the LGWAN, and relays the service requests to a second segment, which is a network segment isolated from the LGWAN and the external network. A second server relays the service request relayed to the second segment to a third segment, which is a network segment exposed to the external network side. A third server relays the service request relayed to the third segment to an application server that provides the application service, A relay system equipped with the following features.

2. The first server relays the service request to the second server using a reverse proxy function. The second server relays the service request to the third server using the first forward proxy function. The third server relays the service request to the application server using a second forward proxy function. The relay system according to claim 1.

3. The aforementioned service request is relayed from the LGWAN side to the application server via encrypted communication. The first server has a first termination function that terminates the encrypted communication of the service request transmitted from within the LGWAN, and a first encrypted communication function that relays the service request terminated by the first termination function to the second server via encrypted communication. The second server has a second termination function that terminates the encrypted communication of the service request relayed from the first server, and a second encrypted communication function that relays the service request terminated by the second termination function to the third server via encrypted communication. The third server has a third termination function that terminates the encrypted communication of the service request relayed from the second server, and a third encrypted communication function that relays the service request terminated by the third termination function to the application server via encrypted communication. The relay system according to claim 1.

4. The system further includes an environment setting unit that generates first configuration information for the reverse proxy function, second configuration information for the first forward proxy function, and third configuration information for the second forward proxy function based on design information relating to communication with the application service provided by the LGWAN-ASP provider that provides the application service, and applies the first configuration information, the second configuration information, and the third configuration information to the first server, the second server, and the third server, respectively. The relay system according to claim 2.

5. A relay method for making application services located on an external network of an LGWAN (Local Government Wide Area Network), which interconnects the internal networks of local government organizations, available from within the LGWAN, The first step involves the first server receiving a service request for the application service transmitted from within the LGWAN in the first segment, which is a network segment exposed to the LGWAN, and relaying the service request to the second segment, which is a network segment isolated from the LGWAN and the external network. The second step involves the second server relaying the service request, which has been relayed to the second segment, to the third segment, which is a network segment exposed to the external network side. A third step involves the third server relaying the service request, which has been relayed to the third segment, to the application server that provides the application service. A relay method having [a certain feature].

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