WO2014030669A1

WO2014030669A1 - Authentication system, management device, and authentication method

Info

Publication number: WO2014030669A1
Application number: PCT/JP2013/072285
Authority: WO
Inventors: 和紀宮澤; 征世秋定; 康樹櫻井
Original assignee: 横河電機株式会社
Priority date: 2012-08-21
Filing date: 2013-08-21
Publication date: 2014-02-27
Also published as: JP2014042095A

Abstract

This management device is equipped with: a communication unit for receiving connection requests from communication devices connected to a network; a control unit that reads from a database a first certificate for authenticating a communication device that has made a communication request when the request is received by the communication unit; and an authentication unit for authenticating the communication device that has transmitted the connection request by using the first certificate read by the control unit.

Description

Authentication system, management apparatus, and authentication method

The present invention relates to an authentication system, a management apparatus, and an authentication method for authenticating a communication device connected to a network.
This application claims priority based on Japanese Patent Application No. 2012-182297 for which it applied to Japan on August 21, 2012, and uses the content here.

Conventionally, distributed control systems (DCS: Distributed Control System) have been constructed in plants, factories, etc. in order to realize advanced automatic operation. In this distributed control system, field devices (measuring instruments, operation devices) called field devices and a control device that controls these devices are connected via communication means. Most communication systems that form the basis of such a distributed control system perform communication by wire. In recent years, however, wireless communication conforming to industrial wireless communication standards such as ISA100.11a and WirelessHART (registered trademark) has been realized.

The above communication system is provided with an authentication system for authenticating a communication device connected to a wired or wireless network using PKI (Public Key Infrastructure) in order to ensure security. In particular, in a communication system that performs communication via a wireless network, the communication device (wireless device) can be connected to the wireless network if the communication device (wireless device) is disposed within the radio wave arrival area. Therefore, in a communication system that performs communication via a wireless network, the above authentication system is essential from the viewpoint of ensuring security.

Here, the above-described authentication system includes a management apparatus that manages a certificate issued by a trusted certificate authority (CA) and authenticates a communication device using the certificate. Specifically, this management apparatus verifies the validity of the certificate presented by the communication device using the certificate managed by itself, and then performs data exchange with the communication device using a challenge / response method. (Message) is sent and received. As a result, the management apparatus authenticates the communication device.

In addition, a first method (PiggyBack method) and a second method (anonymous connection method) are examples of methods by which the communication device presents a certificate to the management apparatus. In the first method, a certificate is presented together with a connection request (join request) to the network. In the second method, a certificate is presented during anonymous connection to the network. The following Patent Document 1 discloses a challenge / response authentication method using a conventional PKI, which is not used in an authentication system provided in a plant or factory.

JP 2008-167107 A

The certificate granted to the communication device (communication device authenticated by the management apparatus of the authentication system) from the above-mentioned certificate authority is generally set with an expiration date in order to increase security. When a certificate with such an expiration date is used, it is necessary to update the certificate by secure communication (secure communication) via the network before the expiration date elapses.

However, some communication devices such as field devices used in plants and factories are stored for a long period of time in addition to those used immediately after shipment. Such a communication device cannot be connected to the network if the expiration date of the certificate elapses during storage. As described above, the certificate is updated by communication via the network. Therefore, if the certificate cannot be connected to the network due to the expiration of the certificate expiration date, the certificate cannot be updated. For this reason, conventionally, certificate expiration management has to be performed for all communication devices that may be connected to the network, which requires extremely complicated work.

In addition, a wireless network compliant with the above-described wireless communication standard ISA100.11a or the like is formed by a wireless device (wireless field device) that performs intermittent operation using a battery as a power source, a wireless router, or the like. Therefore, it has the characteristic that it is power saving and low speed (the communication band is narrow). Due to such characteristics, the size of a packet transmitted / received via the wireless network is limited to about 100 bytes (for example, 128 bytes). Data indicating the process amount such as pressure, flow rate, temperature, etc. measured by the wireless device is communicated in units of this packet.

However, the certificate used for authentication of the wireless device has a data amount of about several kilobytes or more, and the data amount is larger than the data indicating the process amount. For this reason, in order to transmit a certificate from a wireless device to a management apparatus, many resources are required. For this reason, resources of a wireless device such as a wireless router arranged on a communication path between the wireless device that transmits the certificate and the management apparatus are consumed. Accordingly, there is a possibility that the replacement time of the battery is advanced, or that the data transmission of the original process amount is hindered.

The present invention provides an authentication system, a management apparatus, and an authentication method capable of simplifying management of a certificate used for authentication of a communication device and reducing resources required for certificate transmission / reception.

(1) According to a first aspect of the present invention, there is a database storing a first certificate used for authenticating a communication device connected to the first network, and when there is a connection request from the communication device. A management apparatus that reads a first certificate for authenticating the communication device that has made the connection request from the database, and uses the first certificate to authenticate the communication device that has made the connection request; It is an authentication system provided with.
According to the first aspect of the present invention, when there is a connection request from a communication device, the first certificate for authenticating the communication device that has made the connection request is read from the database and read. The management device authenticates the communication device that has made a connection request using the first certificate.

(2) In the first aspect of the present invention, the first certificate stored in the database may be verified using a second certificate for verifying the first certificate.

(3) In the first aspect of the present invention, the server further includes a server device connected to the management device via a second network different from the first network and providing information stored in the database. The device may obtain the first certificate stored in the database from the server device.

(4) In the first aspect of the present invention, a certificate authority server device that issues the first certificate stored in the database may be further provided.

(5) In the first aspect of the present invention, the first certificate is assigned to the communication device, and the management device authenticates the communication device that has made the connection request. If one certificate is not stored in the database, the first certificate given to the communication device that has made the connection request is acquired, and authentication of the communication device that has made the connection request May be performed.

(6) In the first aspect of the present invention, the first network may be a wireless network, and the second network may have a wider communication band than the first network.

(7) In the first aspect of the present invention, the database stores the first certificate and an identifier that uniquely identifies the communication device in association with each other, and the management device receives the communication device from the communication device, A communication unit that receives the connection request and an identifier that uniquely identifies the communication device; a control unit that reads the first certificate associated with the identifier received by the communication unit from the database; A controller that authenticates the communication device that has made the connection request using the first certificate read by the controller.

(8) In the first aspect of the present invention, the authentication unit encrypts the first message using a first public key included in the first certificate, and the communication unit encrypts the authentication unit. The first message is transmitted to the communication device, the communication unit receives the second message encrypted using a second public key from the communication device, and the authentication unit receives the second message. The message may be decrypted using a secret key, and the communication device may be authenticated based on whether the first message matches the second message.

(9) In the first aspect of the present invention, the communication device may not hold the first certificate.

(10) In the first aspect of the present invention, the first certificate stored in the database may include a public key, and a secret key corresponding to the public key may be held by the communication device. .

(11) In the first aspect of the present invention, an expiration date is set for the first certificate, and before the expiration date, the database has the first certificate with a new expiration date set. It may be updated to a certificate.

(12) In the first aspect of the present invention, the management device may authenticate the communication device using a challenge / response method.

(13) In the first aspect of the present invention, when the authentication of the communication device is successful, the management apparatus accepts the connection request from the communication device and connects the communication device to the first network. May be.

(14) In the first aspect of the present invention, when the authentication of the communication device is not successful, the management device rejects the connection request from the communication device, and the communication device May not be connected to the first network.

(15) In the first aspect of the present invention, the management device may not receive the first certificate from the communication device.

(16) In the first aspect of the present invention, the management apparatus receives an anonymous connection request as a connection request from the communication device, causes the communication device to anonymously connect to the first network, and performs the communication. When the device authentication is successful, the management device may switch the communication device from an anonymous connection to a regular connection and connect the communication device to the first network.

(17) In the first aspect of the present invention, when the authentication of the communication device is not successful, the management apparatus may disconnect the anonymous connection of the communication device from the first network.

(18) In the first aspect of the present invention, when receiving a connection request from the communication device, the management apparatus may verify the first certificate using the second certificate.

(19) In the second aspect of the present invention, the communication unit that receives a connection request from a communication device connected to a network, and the communication unit that performs the connection request when the communication unit receives the connection request. A control unit that reads a first certificate for authenticating the communication device from a database, and an authentication unit that authenticates the communication device that has transmitted the connection request using the first certificate read by the control unit And a management device comprising:

(20) A third aspect of the present invention is the first certificate used for receiving a connection request from a communication device connected to a network and authenticating the communication device when the connection request is received. The first certificate for authenticating the communication device that has made the connection request is read from the database that stores the connection request, and the communication device that has made the connection request is authenticated using the read first certificate. This is the authentication method to be performed.

According to one aspect of the present invention, when there is a connection request from a communication device, the first certificate for authenticating the communication device that has made the connection request is read from the database, and the read first certificate is It authenticates the communication device that made the connection request. For this reason, since the management of the first certificate for authenticating the communication device only needs to manage the certificate stored in the database, the management of the certificate used for authentication of the communication device can be simplified. In addition, since the certificate is not transmitted / received to / from the communication device that has made the connection request, resources required for the certificate transmission / reception can be reduced.

It is a block diagram which shows the whole structure of the authentication system by 1st Embodiment of this invention. It is a figure for demonstrating PKI used by 1st Embodiment of this invention. It is a figure which shows an example of the incorporating method of the certificate in 1st Embodiment of this invention. It is a flowchart which shows 1st operation | movement of the authentication system by 1st Embodiment of this invention. It is a timing chart which shows the 1st operation | movement of the authentication system by 1st Embodiment of this invention. It is a flowchart which shows 2nd operation | movement of the authentication system by 1st Embodiment of this invention. It is a timing chart which shows the 2nd operation | movement of the authentication system by 1st Embodiment of this invention. It is a block diagram which shows the whole structure of the authentication system by 2nd Embodiment of this invention. It is a figure for demonstrating PKI used by 3rd Embodiment of this invention. It is a flowchart which shows operation | movement of the authentication system by 4th Embodiment of this invention.

Hereinafter, an authentication system, a management apparatus, and an authentication method according to first to fourth embodiments of the present invention will be described in detail with reference to the drawings.

[First Embodiment]
FIG. 1 is a block diagram showing the overall configuration of an authentication system 1 according to the first embodiment of the present invention. As shown in FIG. 1, the authentication system 1 of the first embodiment includes wireless devices 10a to 10c (communication devices),

wireless routers

20a and 20b, a backbone router 30, a system manager 40a (management device), and an authentication database 50 (database). ). The system manager 40a uses the authentication database 50 to authenticate the wireless devices 10a to 10c connected to the wireless network N1 (network). The numbers of the wireless devices 10a to 10c and the

wireless routers

20a and 20b shown in FIG. 1 are arbitrary.

1 is formed by the wireless devices 10a to 10c, the

wireless routers

20a and 20b, and the backbone router 30 under the management control of the system manager 40a. The wireless network N1 is a wireless network having the characteristics of power saving and low speed (communication band is narrower than a predetermined value). The backbone network N2 to which the backbone router 30 and the system manager 40a are connected is a wired or wireless network serving as the backbone of the authentication system 1 having the characteristic that it is a broadband (communication band is wider than a predetermined value).

The wireless devices 10a to 10c are wireless field devices installed in plants or factories such as sensor devices such as flow meters and temperature sensors, valve devices such as flow control valves and on-off valves, and actuator devices such as fans and motors. . These wireless devices 10a to 10c perform intermittent operation using a battery as a power source, and perform wireless communication conforming to ISA100.11a which is a wireless communication standard for industrial automation.

Here, the wireless devices 10a to 10c cannot be properly connected to the wireless network N1 unless authenticated by the system manager 40a. Therefore, certificates C11 to C13 (see FIG. 2) indicating that the wireless devices 10a to 10c themselves are legitimate wireless devices are prepared in advance. Although details will be described later, since the certificates C11 to C13 are stored in the authentication database 50, they are not necessarily held in the wireless devices 10a to 10c.

The

wireless routers

20a and 20b perform wireless communication conforming to the wireless communication standard ISA100.11a with the wireless devices 10a to 10c and the backbone router 30. That is, the

wireless routers

20a and 20b relay data transmitted and received between the wireless devices 10a to 10c and the backbone router 30. These

wireless routers

20a and 20b also perform intermittent operation using a battery as a power source, similarly to the wireless devices 10a to 10c. The wireless devices 10a to 10c, the

wireless routers

20a and 20b, and the backbone router 30 are wirelessly connected to each other, thereby forming a star-mesh wireless network N1. Instead of the

wireless routers

20a and 20b, wireless devices having the functions (relay function) of the

wireless routers

20a and 20b may be provided.

The backbone router 30 connects the wireless network N1 and the backbone network N2, and relays various data transmitted and received between the wireless devices 10a to 10c and the system manager 40a. The backbone router 30 operates continuously with, for example, DC power supplied from the backbone network N2 or DC power supplied via a path different from the backbone network N2. The backbone router 30 performs wireless communication conforming to the wireless communication standard ISA100.11a.

The system manager 40a operates continuously with, for example, power supplied from a commercial power source, and manages and controls the authentication system 1 in an integrated manner. For example, the system manager 40a controls wireless communication performed via the wireless network N1. Specifically, the system manager 40a performs assignment control of wireless communication resources (time slots and communication channels) to the wireless devices 10a to 10c, the

wireless routers

20a and 20b, and the backbone router 30. As a result, the system manager 40a realizes wireless communication by TDMA (Time Division Multiple Access) via the wireless network N1.

Further, the system manager 40a authenticates the wireless devices 10a to 10c connected to the wireless network N1 using the certificates C11 to C13 and the certificate C20 (see FIG. 2) stored in the authentication database 50. Specifically, when there is a connection request from the wireless devices 10a to 10c, the system manager 40a converts the certificates C11 to C13 (see FIG. 2) stored in the authentication database 50 into the certificate C20 (see FIG. 2). ) To verify. Thereafter, the system manager 40a authenticates the wireless devices 10a to 10c that have made connection requests by the challenge / response method.
As shown in FIG. 1, the system manager 40 a includes a communication unit 41, a control unit 42 a, and an authentication unit 43.
The communication unit 41 receives connection requests from the wireless devices 10a to 10c connected to the wireless network N1.
When the communication unit 41 receives a connection request, the control unit 42a uses a certificate (for example, the certificate C11) for authenticating the wireless device (for example, the wireless device 10a) that has made the connection request, as an authentication database 50. Read from.
The authentication unit 43 authenticates the wireless device (for example, the wireless device 10a) that transmitted the connection request, using the certificate (for example, the certificate C11) read by the control unit 42a.

The authentication database 50 is a database in which information necessary for authenticating the wireless devices 10a to 10c is stored. Specifically, the authentication database 50 stores certificates C11 to C13 (first certificate: see FIG. 2) and certificate C20 (second certificate: see FIG. 2). Certificates C11 to C13 are certificates for the wireless devices 10a to 10c. The certificate C20 is a certificate issued by a trusted certificate authority, and is a certificate C20 (second certificate: see FIG. 2) used to verify the certificates C11 to C13. The certificates C11 to C13 for the wireless devices 10a to 10c are stored in the authentication data database 50 in association with an identifier (for example, EUI64 address) that uniquely identifies the wireless devices 10a to 10c.

The certificates C11 to C13 for the wireless devices 10a to 10c are originally held in the wireless devices 10a to 10c, respectively. However, in the first embodiment, the certificates C11 to C13 are stored in the authentication database 50 and are not held in the wireless devices 10a to 10c. This is to simplify the management of certificates for the wireless devices 10a to 10c. Another reason is to eliminate resources necessary for transmitting and receiving the certificates C11 to C13 by eliminating transmission and reception of the certificates C11 to C13 via the wireless network N1.

FIG. 2 is a diagram for explaining a PKI (Public Key Infrastructure) used in the first embodiment of the present invention. As shown in FIG. 2, the certificates C11 to C13 for the wireless devices 10a to 10c and the certificate C20 used to verify these certificates C11 to C13 are requested to be issued by the system manager 40a to the certificate authority 60. (P11). In response to this request, the certificate authority 60 issues certificates C11 to C13 and a certificate C20 to the system manager 40a (P12). The certificate authority 60 is a certificate authority that the system manager 40a can trust, for example, a public certificate authority. The certificates C11 to C13 and certificate C20 issued by the certificate authority 60 are stored in the authentication database 50. The certificates C11 to C13 for the wireless devices 10a to 10c may be stored in the authentication database 50 and held in the wireless devices 10a to 10c, respectively. In this case, for example, the certificate C11 is transmitted from the certificate authority 60 to the wireless device 10a (P13).

Although not shown in FIG. 2, the certificates C11 to C13 and the certificate C20 include different public keys. The private keys corresponding to the public keys included in the certificates C11 to C13 are held in the wireless devices 10a to 10c, respectively. The private key corresponding to the public key included in the certificate C20 is held in the certificate authority 60 and is strictly managed.

When a connection request for the wireless network N1 is received from the wireless device 10a, as shown in FIG. 2, the authentication of the wireless device 10a using the certificate C11 and the certificate 20 stored in the authentication database 50 is performed by the system manager 40a. (P14). When a connection request for the wireless network N1 is received from the wireless device 10b, the wireless device 10b is authenticated using the certificate C12 and the certificate 20 stored in the authentication database 50. When a connection request for the wireless network N1 is received from the wireless device 10c, the wireless device 10c is authenticated using the certificate C13 and the certificate 20 stored in the authentication database 50.

Next, a method for incorporating the certificates C11 to C13 and the certificate C20 issued by the certificate authority 60 will be described. FIG. 3 is a diagram showing an example of a method for incorporating the certificates C11 to C13 in the first embodiment of the present invention. A wireless network N1 realized in a plant or factory is different from a general network such as the Internet. The wireless network N1 is designed by carefully planning the installation location, number, type, and the like of the devices (the wireless devices 10a to 10c, the

wireless routers

20a and 20b, and the backbone router 30) that constitute the wireless network N1. For this reason, when the design of the wireless network N1 is completed, a wireless device that needs to be connected to the wireless network N1 is determined, and a certificate necessary for the authentication is also determined.

When the design of the wireless network N1 is completed, the vendor V of the wireless device issues a certificate C11 to C13 and a certificate C20 for the wireless devices 10a to 10c that need to be connected to the wireless network N1 to the certificate authority 60. Request. In response to this, the certificate authority 60 issues certificates C11 to C13 and a certificate C20 for the wireless devices 10a to 10c (P21). Upon obtaining the certificates C11 to C13 and the certificate C20 issued from the certificate authority 60, the vendor V incorporates the certificates C11 to C13 into the wireless devices 10a to 10c, respectively (P22). At the same time, the vendor V copies the certificates C11 to C13 and the certificate C20 to a computer-readable recording medium M such as a CD-ROM or DVD (registered trademark) -ROM (P23). Then, the vendor V transfers the wireless device (in the example shown in FIG. 3, the wireless device 10a) whose certificate has been installed to the user U (for example, a person who operates the authentication system 1 in a plant or factory). Ship (P24). The vendor V sends the recording medium M on which the certificates C11 to C13 and the certificate C20 are recorded to the user U (P25).

The user U installs the wireless device 10a sent from the vendor V at a position defined in the design stage, and the certificates C11 to C13 and the certificate C20 recorded on the recording medium M sent from the vendor V. Is incorporated into the system manager 40a (P26). Since the certificate C20 is data serving as a basis for maintaining the reliability of the authentication system 1, the integrity (integrity) of the certificate C20 is confirmed using a secure method and is incorporated in the system manager 40a. The certificates C11 to C13 incorporated in the system manager 40a are stored in the authentication data database 50 in association with identifiers that uniquely identify the wireless devices 10a to 10c. The certificate C20 incorporated in the system manager 40a is stored alone in the authentication data database 50. In this manner, the certificates C11 to C13 and the certificate C20 are incorporated into the authentication database 50.

Here, if the user U requests the vendor V with reference to the network design document ND of the wireless network N1 (P27), it is a certificate of the wireless device to be connected to the wireless network N1, and is stored in the authentication database 50. It is possible to obtain what is not stored.
In addition, when an expiration date is set for the certificates C11 to C13, the certificate C11 to C13 or a certificate in which a new expiration date is set by the user U requesting the vendor V before the expiration date is expired. If the certificate C20 is obtained, the certificates C11 to C13 or the certificate C20 stored in the authentication database 50 can be updated. Since the certificates C11 to C13 and the certificate C20 may be disclosed, the route through which the user U obtains the recording medium M from the vendor V can be selected as appropriate.

Next, the operation of the authentication system 1 in the above configuration will be described. Hereinafter, the case where the wireless device to be connected to the wireless network N1 is the wireless device 10a will be described. An operation when performing authentication of the wireless device 10a will be described as an example. Here, the operation of the authentication system 1 is an operation when a certificate is presented by a method according to the PiggyBack method (first operation) and an operation when a certificate is presented by the anonymous connection method. (Second operation). Below, these 1st, 2nd operation | movement is demonstrated in order.

<First operation>
FIG. 4 is a flowchart showing a first operation of the authentication system 1 according to the first embodiment of the present invention. FIG. 5 is a timing chart showing the first operation of the authentication system 1. As shown in FIGS. 4 and 5, first, an offline operation for preparing a certificate used for authenticating the wireless device 10a is performed (step S10). Next, an online operation for authenticating the wireless device 10a using the certificate prepared in the offline mode is performed (step S20).

When the offline operation is started, first, the process of acquiring the certificate C20 issued by the certificate authority 60 and storing it in the authentication database 50 is performed by the control unit 42a of the system manager 40a (step S11). For example, the control unit 42a of the system manager 40a reads the certificate C20 recorded on the recording medium M (recording medium M sent from the vendor V) described with reference to FIG. Done.

Next, processing for obtaining the certificates C11 to C13 issued by the certificate authority 60 and verifying the validity of these certificates C11 to C13 using the certificate C20 is performed by the control unit 42a of the system manager 40a ( Step S12). For example, the certificates C11 to C13 recorded on the recording medium M described with reference to FIG. 3 (the recording medium M shipped from the vendor V) are read, and the certificate C20 stored in the authentication database 50 in the process of step S11. The control unit 42a of the system manager 40a performs processing for verifying the validity of the certificates C11 to C13 using the certificate C20.

Next, whether or not the certificates C11 to C13 are valid is determined by the control unit 42a of the system manager 40a (step S13). If the control unit 42a of the system manager 40a determines that the certificates C11 to C13 are invalid (when the determination result is “NO”), the series of processing illustrated in FIG. 4 ends. On the other hand, when the control unit 42a of the system manager 40a determines that the certificates C11 to C13 are valid (when the determination result is “YES”), the identifier uniquely identifies the wireless devices 10a to 10c. A process of storing the certificates C11 to C13 in association with each other in the authentication database 50 is performed by the control unit 42a (step S14). When the above processing is completed, the offline operation is terminated and the online operation is started.

When the online operation is started, the system manager 40a waits to receive a connection request via the wireless network N1 based on the control of the control unit 42a (step S21). In this state, if a connection request for the wireless network N1 is transmitted from the wireless device 10a, the connection request is received by the communication unit 41 of the system manager 40a (step S22).
Here, if the original piggyback method is used, a certificate for the wireless device 10a is transmitted from the wireless device 10a to the system manager 40a together with the connection request. In the first embodiment, the connection request is made without sending the certificate. Only sent. For this reason, the communication unit 41 of the system manager 22 receives only the connection request for the wireless device 10a.

When the communication unit 41 receives a connection request from the wireless device 10a, the control unit 42a of the system manager 40a reads the certificate C11 associated with the identifier of the wireless device 10a from the authentication database 50 (step S23). The identifier of the wireless device 10a used when searching the authentication database 50 is transmitted from the wireless device 10a along with the connection request.

When the control unit 42a reads the certificate C11 for the wireless device 10a, the authentication unit 43 of the system manager 40a transmits / receives data (message) to / from the wireless device 10a by the challenge / response method. Authentication is performed (step S24).
Specifically, first, the authentication unit 43 of the system manager 40a encrypts a special message using the public key included in the certificate C11 read from the authentication database 50 in step S23, and the encrypted message is The communication unit 41 transmits the wireless device 10a via the wireless network N1 (challenge).

When receiving the message transmitted from the communication unit 41 of the system manager 40a, the wireless device 10a decrypts the message using the private key held by itself. Since the message from the system manager 40a is encrypted using the public key included in the certificate C11 for the wireless device 10a, it can be decrypted only with the private key held in the wireless device 10a. .

When the message from the system manager 40a is decrypted, the wireless device 10a presents the decrypted message to the system manager 40a in a secure manner (response).
For example, the wireless device 10a encrypts a message (decrypted message) using the public key of the system manager 40a, and transmits the encrypted message to the system manager 40a.

Note that the message transmitted from the wireless device 10a to the system manager 40a can be decrypted only with the private key held and managed by the system manager 40a. Therefore, the wireless device 10a can present the decrypted message to the system manager 40a in a secure manner. Alternatively, the wireless device 10a regards a part of the decrypted message as a target key and encrypts the decrypted message or a part of the message with the key, thereby presenting the decrypted message or the message part to the system manager 40a in a secure manner. it can.

When the communication unit 41 receives the message presented from the wireless device 10a, the authentication unit 43 of the system manager 40a determines whether or not the authentication of the wireless device 10a is successful from the content of the message transmitted to the wireless device 10a ( Step S25). Specifically, whether or not the wireless device 10a has been successfully authenticated depends on whether or not the message transmitted to the wireless device 10a matches the message presented from the wireless device 10a according to a predetermined verification rule. The authentication unit 43 determines whether or not.

When the authentication unit 43 determines that the authentication is successful (when the determination result of step S25 is “YES”), the control unit 42a of the system manager 40a accepts a connection request from the wireless device 10a, and the communication unit 41 Notifies the wireless device 10a of an authentication result indicating that the authentication is successful (step S26). Through the above processing, the wireless device 10a is normally connected to the wireless network N1, and communication via the wireless network N1 becomes possible under the management of the system manager 40a.

On the other hand, when the authentication unit 43 determines that the authentication has failed (when the determination result of step S25 is “NO”), the control unit 42a of the system manager 40a rejects the connection request from the wireless device 10a. Then, the communication unit 41 notifies the wireless device 10a of an authentication result indicating that the authentication has failed (step S27).
Through the above processing, since the connection request to the wireless network N1 of the wireless device 10a is rejected, the wireless device 10a is not connected to the wireless network N1 and cannot communicate via the wireless network N1.

<Second operation>
FIG. 6 is a flowchart showing a second operation of the authentication system 1 according to the first embodiment of the present invention. FIG. 7 is a timing chart showing the second operation of the authentication system 1. 6 and 7, the same reference numerals are given to steps in which the same processes as those shown in FIGS. 4 and 5 are performed. As shown in FIGS. 6 and 7, even in the second operation, an offline operation is first performed (step S10), and then an online operation is performed (step S20). However, since the offline operation in the second operation is the same as the offline operation in the first operation, description of the offline operation is omitted below, and only the online operation is described.

When the online operation starts, the system manager 40a waits to receive a connection request via the wireless network N1 based on the control of the control unit 42a (step S21). In this state, when an anonymous connection request for the wireless network N1 is transmitted from the wireless device 10a, the anonymous connection request is received and accepted by the communication unit 41 of the system manager 40a, and based on the control of the control unit 42a. An anonymous connection is established between the wireless device 10a and the system manager 40a (step S31). Here, as in the conventional anonymous connection method, the certificate is not sent from the wireless device 10a to the system manager 40a.

When the anonymous connection with the wireless device 10a is established by the control unit 42a, the control unit 42a of the system manager 40a reads the certificate C11 associated with the identifier of the wireless device 10a from the authentication database 50 (step S23). ). Note that the identifier of the wireless device 10 a used when searching the authentication database 50 is transmitted from the wireless device 10 a accompanying the anonymous connection request and received by the communication unit 41.

When the control unit 42a reads the certificate C11 for the wireless device 10a, the control unit 42a of the system manager 40a transmits / receives data (message) to / from the wireless device 10a via the communication unit 41 by the challenge / response method. Then, the authentication of the wireless device 10a is performed by the authentication unit 43 (step S24). Note that the authentication of the wireless device 10a by the challenge / response method is performed by the same processing as the first operation, and thus detailed description thereof is omitted.

Next, the system manager 40a determines whether or not the authentication of the wireless device 10a is successful (Step S25). When the authentication unit 43 determines that the authentication is successful (when the determination result is “YES”), the control unit 42a of the system manager 40a authenticates the anonymous connection established with the wireless device 10a. Processing for switching to connection is performed (step S32). Through the above processing, the wireless device 10a is normally connected to the wireless network N1, and communication via the wireless network N1 becomes possible under the management of the system manager 40a.

On the other hand, when the authentication unit 43 determines that the authentication has failed (when the determination result of step S25 is “NO”), the control unit 42a of the system manager 40a performs an anonymous connection with the wireless device 10a. The process which cut | disconnects is performed (step S33). As a result of the above processing, the wireless device 10a is disconnected from the wireless network N1, and therefore cannot communicate via the wireless network N1.

As described above, in the first embodiment, the authentication database 50 for storing the certificates C11 to C13 (verified using the certificate C20) for the wireless devices 10a to 10c is provided. When the communication unit 41 receives a connection request or an anonymous connection request from the wireless device 10a, the control unit 42a of the system manager 40a reads the certificate C11 for the wireless device 10a from the authentication database 50 and performs authentication. The unit 43 authenticates the wireless device 10a.

Thereby, the management of the certificates C11 to C13 for the wireless devices 10a to 10c may be performed for those stored in the authentication database 50, and it is not necessary to perform the management for those held in the wireless devices 10a to 10c. Therefore, management of the certificates C11 to C13 can be simplified. In addition, regardless of which of the first and second operations described above, certificates C11 to C13 are not transmitted / received via the wireless network N1. Therefore, it is possible to reduce resources required for transmitting / receiving the certificates C11 to C13.

[Second Embodiment]
FIG. 8 is a block diagram showing the overall configuration of the authentication system 2 according to the second embodiment of the present invention. In FIG. 8, the same components as those shown in FIG. 1 are denoted by the same reference numerals. As shown in FIG. 8, the authentication system 2 of the second embodiment includes an authentication server 70 (server device) that provides a certificate stored in the authentication database 50, and connects the system manager 40b and the authentication server 70 to a LAN ( In this configuration, the network N3 such as a Local Area Network is connected.
In the second embodiment, unlike the system manager 40a of the first embodiment, the system manager 40b includes a control unit 42b instead of the control unit 42a.

In the authentication system 1 of the first embodiment described above, the system manager 40a is directly connected to the authentication database 50, and the system manager 40a reads the certificates C11 to C13 from the authentication database 50. On the other hand, in the authentication system 2 of the second embodiment, the control unit 42b of the system manager 40b makes a read request for the certificates C11 to C13 to the authentication server 70, and the certificates C11 to C13 according to the request are received. The authentication server 70 provides the control unit 42b. When the system manager 40b makes a read request for the certificates C11 to C13, it is necessary to provide the authentication server 70 with an identifier that uniquely identifies the wireless devices 10a to 10c.

As described above, in the second embodiment, since the authentication server 70 that provides the certificate stored in the authentication database 50 is provided, the load on the system manager 40b can be reduced. 8 illustrates a configuration in which one authentication server 70 is connected to the system manager 40b via the network N3, but a plurality of authentication servers 70 are connected to the system manager 40b via the network N3. It may be a configuration. Further, the authentication server 70 may be connected to the system manager 40b via the backbone network N2.

[Third Embodiment]
Next, a third embodiment of the present invention will be described. In the first and second embodiments described above, the wireless devices 10a to 10 using the certificates C11 to C13 and the certificate C20 issued by the certificate authority 60 (for example, a public certificate authority) that can be trusted by the

system managers

40a and 40b. 10c authentication was performed. On the other hand, in the third embodiment, the wireless devices 10a to 10c are authenticated using a certificate issued by a certificate authority uniquely constructed by the user U (P33).
In the third embodiment, unlike the system manager 40a of the first embodiment, the system manager 40c includes a control unit 42c instead of the control unit 42a.

FIG. 9 is a diagram for explaining the PKI used in the third embodiment of the present invention. As shown in FIG. 9, in the third embodiment, a certificate authority server device 80 that is a certificate authority uniquely constructed by the user U is provided. The certificate authority server apparatus 80 includes certificates C31 to C33 (first certificate) used for authenticating the wireless devices 10a to 10c, and certificates used to verify these certificates C31 to C33. C20 is issued (P32). The certificate authority server device 80 may be connected to the network N3 provided in the authentication system 2 shown in FIG. 8, for example, but may be separated from the authentication system 2 in order to improve security.

The certificates C31 to C33 and certificate C20 newly issued by the certificate authority server apparatus 80 are stored in the authentication database 50, and the wireless devices 10a to 10c using the certificates C31 to C33 and the certificate C20 are stored by the system manager 40c. Authentication is performed. However, it is not easy to update the secret key stored in the wireless devices 10a to 10c.

Therefore, as shown in FIG. 9, the system manager 40c retrieves, for example, the certificate C11 corresponding to the wireless device 10a from the authentication database 50, the control unit 42c presents the public key included therein, and presents the certificate authority server device 80. A signature request is made (P31). If such a certificate authority server device 80 is provided, it is possible to authenticate a wireless device using PKI as described above using a certificate authority uniquely constructed by the user U. Further, the certificate C31 generated in this way may be incorporated into the wireless device 10a via the system manager 40c. When the wireless devices 10a to 10c provide an interface for setting a secret key, the certificate including the public key that the certificate authority server device 80 pairs with the secret key as performed by the vendor V in FIG. May be generated and incorporated via the system manager 40c.

[Fourth Embodiment]
Next, a fourth embodiment of the present invention will be described. In the first and second embodiments described above, the

system managers

40a and 40b authenticate the wireless devices 10a to 10c using the certificates C11 to C13 stored in the authentication database 50. In the fourth embodiment, the certificates C11 to C13 held in the wireless devices 10a to 10c even when the certificates C11 to C13 for authenticating the wireless devices 10a to 10c are not stored in the authentication database 50. By acquiring, the wireless devices 10a to 10c can be authenticated (fallback).
The configuration of the authentication system of the fourth embodiment is the same as the configuration of the authentication system 1 of the first embodiment shown in FIG.

Therefore, in the fourth embodiment, it is assumed that the certificates C11 to C13 whose expiration date has not passed are held in the wireless devices 10a to 10c. The overall configuration of the authentication system according to the fourth embodiment is the same as that of the authentication system 1 according to the first embodiment shown in FIG. 1 or the authentication system 2 according to the second embodiment shown in FIG.

FIG. 10 is a flowchart showing the operation of the authentication system according to the fourth embodiment of the present invention. The flowchart shown in FIG. 10 shows an operation (second operation) when a certificate is presented by the anonymous connection method, similarly to the flowchart shown in FIG. In FIG. 10, the offline operation (step S10) is omitted, and only the online operation (step S20) is shown. In FIG. 10, steps in which the same processing as that shown in FIG. 6 is performed are denoted by the same reference numerals.

When the online operation is started, the system manager 40a enters a state of waiting for reception of a connection request via the wireless network N1, as in the second operation in the first embodiment, based on the control of the control unit 42a. (Step S21). In this state, when an anonymous connection request for the wireless network N1 is transmitted from the wireless device 10a, the anonymous connection request is received and accepted by the communication unit 41 of the system manager 40a, and the control unit 42a receives the wireless device 10a. An anonymous connection is established between the system manager 40a and the system manager 40a (step S31). Here, as in the conventional anonymous connection method, the certificate is not sent from the wireless device 10a to the system manager 40a.

When the anonymous connection with the wireless device 10a is established, the control unit 42a of the system manager 40a reads the certificate C11 associated with the identifier of the wireless device 10a from the authentication database 50 (step S23). The identifier of the wireless device 10a used when searching the authentication database 50 is transmitted from the wireless device 10a along with the anonymous connection request and received by the communication unit 41.

Next, the control unit 42a of the system manager 40a determines whether or not the certificate C11 has been successfully read from the authentication database 50 (step S41). When the control unit 42a determines that the certificate C11 has been successfully read (when the determination result is “YES”), the authentication unit 43 of the system manager 40a performs the challenge / response method as in the first embodiment. Thus, the wireless device 10a is authenticated (step S24).

On the other hand, when the control unit 42a determines that the reading of the certificate C11 has failed (when the determination result is “NO”), the authentication unit 43 of the system manager 40a sends the certificate to the wireless device 10a. A transmission request for C11 is made via the communication unit 41, and the communication unit 41 obtains the certificate C11 from the wireless device 10a (step S42).
Then, using the public key included in the certificate C11 acquired from the wireless device 10a, the authentication unit 43 authenticates the wireless device 10a by the challenge / response method (step S24).

If the authentication unit 43 succeeds in authenticating the wireless device 10a, the system manager 40a performs a process of switching the anonymous connection established with the wireless device 10a to a regular connection as in the first embodiment. Is performed by the controller 42a (step S32). If the authentication unit 43 fails to authenticate the wireless device 10a, the control unit 42a of the system manager 40a performs processing for disconnecting the anonymous connection with the wireless device 10a, as in the first embodiment. (Step S33).

As described above, in the fourth embodiment, when the certificates C11 to C13 for the wireless devices 10a to 10c are not stored in the authentication database 50, the certificates C11 to C13 held in the wireless devices 10a to 10c are stored. And the authentication unit 43 authenticates the wireless devices 10a to 10c. Therefore, for example, even when a failure occurs in the authentication database 50, the wireless devices 10a to 10c can be connected to the wireless network N1 by the same method as before.

The authentication system, the management apparatus, and the authentication method according to the first to fourth embodiments of the present invention have been described above. However, the present invention is not limited to the first to fourth embodiments described above, and is within the scope of the present invention. Can be changed freely. For example, in the first to fourth embodiments, the certificates C11 to C13 used for authentication of the wireless devices 10a to 10c are used using the certificate C20 when offline (step S10 in FIGS. 4 and 6). It was verified in advance and only the verified data was stored in the authentication database 50. However, the verification of the certificates C11 to C13 when offline (verification using the certificate C20) is not performed, and when the communication unit 41 receives a connection request or an anonymous connection request from the wireless devices 10a to 10c while online, The verification may be performed.

In the first to fourth embodiments, the aspect in which the backbone router 30 and the

system managers

40a, 40b, and 40c are separately provided has been described. However, the present invention is directed to the backbone router 30 and the

system managers

40a, 40b, and 40c. And may be integrated. In such a case, the backbone network N2 can be omitted. In the first to fourth embodiments, examples of authenticating the wireless devices 10a to 10c connected to the wireless network N1 have been described. However, the present invention is also applicable to authentication of communication devices connected to a wired network. can do.

The present invention requires an authentication system, a management apparatus, an authentication method, and the like that are required to simplify the management of a certificate used for authentication of a communication device, and to reduce the resources required for transmitting and receiving the certificate. Can be applied to.

DESCRIPTION OF SYMBOLS 1, 2 Authentication system 10a-

10c Wireless device

40a, 40b, 40c System manager 41

Communication part

42a, 42b, 42c Control part 43 Authentication part 50 Authentication database 70 Authentication server 80 Certification authority server apparatus C11-C13 Certificate C20 Certificate C31 ~ C33 Certificate N1 Wireless network N3 network

Claims

A database storing a first certificate used to authenticate a communication device connected to the first network;
When there is a connection request from the communication device, a first certificate for authenticating the communication device that has made the connection request is read from the database, and the connection request is made using the first certificate. A management device for authenticating the communication device;
An authentication system comprising:
The authentication system according to claim 1, wherein the first certificate stored in the database is verified using a second certificate for verifying the first certificate.
A server device connected to the management device via a second network different from the first network, and providing information stored in the database;
The authentication system according to claim 1, wherein the management device acquires the first certificate stored in the database from the server device.
The authentication system according to claim 1, further comprising a certificate authority server device that issues the first certificate stored in the database.
The communication device is provided with the first certificate,
If the first certificate for authenticating the communication device that has made the connection request is not stored in the database, the management apparatus is assigned to the communication device that has made the connection request The authentication system according to claim 1, wherein the first certificate is acquired and the communication device that has made the connection request is authenticated.
The first network is a wireless network;
The authentication system according to claim 1, wherein the second network has a wider communication band than the first network.
The database stores the first certificate and an identifier that uniquely identifies the communication device in association with each other,
The management device
A communication unit that receives from the communication device the connection request and an identifier that uniquely identifies the communication device;
A control unit for reading out the first certificate associated with the identifier received by the communication unit from the database;
A controller that authenticates the communication device that has made the connection request using the first certificate read by the controller;
The authentication system according to claim 1, further comprising:
The authentication unit encrypts the first message using a first public key included in the first certificate,
The communication unit transmits the first message encrypted by the authentication unit to the communication device,
The communication unit receives a second message encrypted using a second public key from the communication device;
8. The authentication unit decrypts the second message using a secret key, and authenticates the communication device based on whether the first message matches the second message. Authentication system.
The authentication system according to claim 1, wherein the communication device does not hold the first certificate.
The first certificate stored in the database includes a public key,
The authentication system according to claim 1, wherein a secret key corresponding to the public key is held by the communication device.
The first certificate has an expiration date,
The authentication system according to claim 1, wherein the database is updated to the first certificate in which a new expiration date is set before the expiration date.
The authentication system according to claim 1, wherein the management apparatus authenticates the communication device using a challenge / response method.
The authentication system according to claim 1, wherein when the authentication of the communication device is successful, the management apparatus accepts the connection request from the communication device and connects the communication device to the first network.
The management apparatus, when the authentication of the communication device is not successful, the control unit rejects the connection request from the communication device and does not connect the communication device to the first network. The described authentication system.
The authentication system according to claim 13, wherein the management apparatus does not receive the first certificate from the communication device.
The management apparatus receives an anonymous connection request as a connection request from the communication device, causes the communication device to anonymously connect to the first network,
The authentication system according to claim 1, wherein when the authentication of the communication device is successful, the management device switches the communication device from an anonymous connection to a regular connection and connects the communication device to the first network.
The authentication system according to claim 16, wherein when the authentication of the communication device is not successful, the management device disconnects the anonymous connection of the communication device from the first network.
3. The authentication system according to claim 2, wherein when receiving a connection request from the communication device, the management device verifies the first certificate using the second certificate.
A communication unit that receives a connection request from a communication device connected to the network;
When the communication unit receives the connection request, a control unit that reads a first certificate for authenticating the communication device that has made the connection request from a database;
An authentication unit that authenticates the communication device that has transmitted the connection request using the first certificate read by the control unit;
A management device comprising:
Receives connection requests from communication devices connected to the network,
A first certificate for authenticating the communication device that made the connection request is read from a database that stores a first certificate used to authenticate the communication device when the connection request is received;
An authentication method for authenticating the communication device that has made the connection request using the read first certificate.