JP2006033624A - Communication control system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To perform control which is not utilized by a person other than a user who takes out stored electronic data when the data are taken out to the other medium, and to allow the manager of the taken-out electronic data to forcibly perform abandoning by a simple and unexpensive constitution. <P>SOLUTION: In a communication control system, an electronic data management server determines the propriety of distribution based on the policy of a user which is obtained from a policy server 5, and enciphers the electronic data in distributing. A certificate validity examining server 7 for examining the validity of the electronic certificate of the user receives the electronic certificate of the user which is transmitted from the user application 2 of a user terminal 1 and examines the validity of the electronic certificate. When the expiration of the electronic certificate is confirmed, the abandoning of the electronic data is urged to the user application 2. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a communication control system that controls access to a database, file server, or the like that holds electronic data and the like based on an accessor's policy and the like, and distributes the electronic data after encryption.

  Conventionally, when electronic data is distributed over a network, it is generally sent by encrypting the electronic data. If the electronic data is an important document, the electronic data is acquired. It is desirable to limit usage even after

In view of such a point, in Patent Document 1, the server determines the usage rule for the user based on the organizational configuration, the user ID, and the usage rule set in the document, and the user's public key A technique is disclosed in which a client device decrypts a document based on the above-mentioned usage rules and presents it to a user.
Japanese Patent Laid-Open No. 2004-30056

  However, in the above-mentioned Patent Document 1, information on an organization configuration, a user ID, and usage rules must be managed on the server side. Furthermore, as described in [Problems to be Solved by the Invention], “There is an employee who submitted a resignation today, and after submitting the resignation, the contents on his hard disk cannot be used, that is, the information cannot be taken outside the company. The mechanism is realized by changing the usage rules stored on the server side. "However, when using content, it is necessary to acquire the usage rules every time in the ticket server. Also, this usage rule must be prepared for each content. Therefore, the management of this usage rule is very heavy, and when an employee leaves the company, as in the example, all usage rules related to that employee must be changed. In other words, when taking out stored electronic data to another medium, a control that can only be used by the person who has taken it out, and a compulsory disposal by the administrator of the electronic data that has been taken out is a mechanism with a very large management load. It can be said that it is adopted.

  Further, in Document 1, since the usage rule is registered in the ticket server when the document file is registered in the document server as described in [Solution], the electronic data stored in the existing file server or DB is stored. There is no mention of the use of.

  The object of the present invention is to provide a control that can be used only by the person who has taken out the electronic data stored in the existing file server or DB to another medium with a simple and inexpensive configuration. It is possible to forcibly discard electronic data by an administrator. In particular, the present invention is characterized in that electronic data held by a user can be discarded at once, or for each electronic data. Furthermore, discarding each electronic data can be performed at once even when a plurality of users hold it.

  In order to achieve the above object, according to a first aspect of the present invention, in a communication control system capable of communicating with a user terminal in which a user application is installed, a policy server for managing a policy for each user, and a file storing electronic data When an electronic data acquisition request is received from the server and the user terminal, a policy acquisition request is made to the policy server, and it is determined whether or not the electronic data can be distributed to the user terminal based on the policy obtained from the policy server. And a management server that controls to acquire electronic data from a file server and encrypt the electronic data and transmit the encrypted data to a user terminal when it is determined that the electronic data can be distributed. A control system is provided.

  According to a second aspect, in the first aspect, a certificate validity verification server for verifying the validity of the user's electronic certificate is further provided, and the certificate validity verification server is sent from the user terminal. If the electronic certificate is revoked as a result of receiving the electronic certificate of the user and verifying the validity of the electronic certificate, the user application is prompted to discard the electronic data. Further, it may be a feature.

  In the second aspect, the discarding may mean that the decryption of the encrypted electronic data is prohibited.

  In this second aspect, the validity of the user's electronic certificate may be revoked by the administrator.

  In the second aspect, an electronic data management server may be provided that manages the ID of electronic data distributed to the user and the electronic certificate of the key used to encrypt the electronic data.

  In the first aspect, the management server may further include an interface that accepts discarding of electronic data in units of electronic data or in units of users.

  According to the present invention, a control that can be used only by the person who has taken out the stored electronic data to another medium with a simple and inexpensive configuration, or the compulsory by the administrator of the extracted electronic data. A communication control system that can be discarded can be provided.

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

  First, a first embodiment of the present invention will be described.

  FIG. 1 is a diagram showing a configuration of a communication control system according to the first embodiment of the present invention.

  As shown in FIG. 1, the communication control system includes an electronic data management server 3 and a certificate issuance / management that can communicate with a user terminal 1 in which a user application 2 is installed, via a network 8 such as the Internet. The server 6 and the certificate validity verification server 7 are configured. The electronic data management server 3 can also communicate with a database (hereinafter referred to as DB) / file server 4 and policy server 5.

  In such a configuration, the user application 2 is installed in the user terminal 1 and executed on the OS. The electronic data management server 3 exchanges information with the DB / file server 4 and the policy server 5 based on a request from the user application 2 and encrypts electronic data. The policy server 5 centrally manages the QoS and security control functions of the user terminals 1 on the network. Here, the policy server 5 manages a policy for determining whether or not to transmit electronic data. The DB / file server 4 stores electronic data. The certificate issuance / management server 6 issues an encryption key and an electronic certificate. The certificate validity verification server 7 verifies the validity of the electronic certificate.

  Hereinafter, a series of operations by the communication control system according to the first embodiment of the present invention will be described in detail with reference to the flowchart of FIG.

  When the user application 2 of the user terminal 1 makes an electronic data acquisition request to the electronic data management server 3 (step S1), the electronic data management server 3 makes a policy acquisition request to the policy server 5 (step S2). This policy acquisition request includes a user ID. Upon receiving this policy acquisition request, the policy server 5 returns a policy corresponding to the user ID to the electronic data management server 3 (step S3).

  Upon receiving this policy, the electronic data management server 3 determines whether or not electronic data can be given to the user application 2 based on the policy. A file acquisition request is made (step S4).

  Upon receiving this request, the DB / file server 4 transmits a file, which is corresponding electronic data, to the electronic data management server 3 (step S5).

  Subsequently, the electronic data management server 3 encrypts this file (step S6), and transmits the encrypted electronic data to the user application 2 (step S7). Then, the user application 2 decrypts the encrypted electronic data (step S8), and thus starts using the electronic data (step S9).

  As described above, according to the first embodiment of the present invention, it is determined whether or not a file can be acquired based on a policy corresponding to a user ID, and the electronic data is encrypted and transmitted to the user application 2 side. Security can be ensured.

  Next, a second embodiment of the present invention will be described.

  This employs a “public key encryption method” as an encryption method.

  Since the basic configuration is the same as in FIG. 1, the same configuration as in FIG. 1 is referred to by the same reference numeral as appropriate, and a duplicate description is omitted.

  Hereinafter, a series of operations by the communication control system according to the second embodiment of the present invention will be described in detail with reference to the flowchart of FIG.

  When the user application 2 of the user terminal 1 makes an electronic data acquisition request to the electronic data management server 3 (step S11), the electronic data management server 3 makes a policy acquisition request to the policy server 5 (step S12). This electronic data acquisition request includes at least a user ID. Upon receiving the policy acquisition request, the policy server 5 returns a policy corresponding to the user ID (step S13). Upon receiving this policy, the electronic data management server 3 determines whether or not electronic data can be given to the user application 2 based on the policy. A file acquisition request is made (step S14). Upon receiving this request, the DB / file server 4 transmits the corresponding file (step S15).

  The electronic data management server 3 sends a public key, private key, and electronic certificate creation request to the electronic certificate issuance / management server 6 (step S16). Upon receiving this request, the certificate issuance / management server 6 creates a public key, a private key, and an electronic certificate and transmits them to the electronic data management server 3 (step S17). Needless to say, the electronic certificate and the key pair (public key / private key) may be created for each user or for each file.

  The electronic data management server 3 encrypts the electronic data with the created public key, encrypts the private key with the user's public key (step S18), creates the electronic certificate of the created public key, and the encrypted electronic data. And the encrypted secret key is transmitted to the user application 2 (step S19). When acquiring these, the user application 2 inquires the certificate validity verification server 7 to verify the validity of the electronic certificate of the public key and the user's electronic certificate created (step S20). The certificate validity verification server 7 transmits the verification result to the user application 2 side (step S21). As a result of the verification, if the user's electronic certificate has not expired, the user application 2 decrypts the private key encrypted with the public key (step S22), and uses the decrypted private key for electronic processing. Data decryption is performed (step S23), and use of electronic data is started (step S24).

  As described above, according to the second embodiment of the present invention, the electronic data is encrypted with the public key created by the certificate issuance / management server 6, and the private key encrypted with the user's public key is encrypted. The security is ensured because it is transmitted together. After using the electronic data, only the electronic data encrypted with the created public key is stored, and when the same electronic data is used again, it goes without saying that the process starts from step 20. In addition, when the user's electronic certificate has expired, the application 2 does not decrypt the encrypted electronic data. For example, even if a retired user tries to view the electronic data after retirement, If the electronic certificate is revoked, it can be disabled.

  Next, a third embodiment of the present invention will be described.

  This employs a “common key encryption method” as an encryption method.

  Since the basic configuration is the same as in FIG. 1, the same configuration as in FIG. 1 is referred to by the same reference numeral as appropriate, and a duplicate description is omitted.

  Hereinafter, a series of operations by the communication control system according to the third embodiment of the present invention will be described in detail with reference to the flowchart of FIG.

  When the user application 2 of the user terminal 1 makes an electronic data acquisition request to the electronic data management server 3 (step S31), the electronic data management server 3 makes a policy acquisition request to the policy server 5 (step S32). The electronic data acquisition request includes a user ID. Upon receiving this policy acquisition request, the policy server 5 returns a policy corresponding to the user ID (step S33). Upon receiving this policy, the electronic data management server 3 determines whether or not electronic data can be given to the user application 2 based on the policy. A file acquisition request is made (step S34).

  Upon receiving this request, the DB / file server 4 transmits the corresponding file (step S35). The electronic data management server 3 creates a common key (step S36), encrypts the electronic data with the common key (step S37), encrypts the common key with the user's public key (step S38), and encrypts it. The common key and the encrypted electronic data are transmitted to the user application 2 (step S39).

  Then, the user application 2 inquires the certificate validity verification server 7 to verify the validity of the user electronic certificate (step S40). The certificate validity verification server 7 transmits the verification result to the user application 2 side (step S41). As a result of the verification, if the user's electronic certificate is valid, the user application 2 decrypts the encrypted common key (step S42), and decrypts the electronic data with the decrypted common key. (Step S43), the use of electronic data is started (step S44).

  As described above, according to the third embodiment of the present invention, since only the user has the user's private key for decrypting the electronic data encrypted with the user's public key, security is further increased. Will be enhanced. In addition, when the user's electronic certificate has expired, the application 2 does not decrypt the encrypted electronic data. For example, even if a retired user tries to view the electronic data after retirement, If the electronic certificate is revoked, it can be disabled.

  Next, a fourth embodiment of the present invention will be described.

  This employs a public key encryption method as an encryption method.

  The basic configuration is as shown in FIG. Compared with the configuration of FIG. 1, only the key / electronic data management server 9 is newly added. Since other configurations are the same as those in FIG. 1, the same configurations as those in FIG. 1 are appropriately referred to by the same reference numerals, and redundant description is omitted. The key / electronic data management server 9 is for registering the created electronic certificate and electronic data, and centrally manages them.

  Hereinafter, a series of operations by the communication control system according to the fourth embodiment of the present invention will be described in detail with reference to the flowchart of FIG.

  When the user application 2 of the user terminal 1 makes an electronic data acquisition request to the electronic data management server 3 (step S51), the electronic data management server 3 makes a policy acquisition request to the policy server 5 (step S52). Upon receipt of this policy acquisition request, the policy server 5 returns a policy (step S53). Upon receiving this policy, the electronic data management server 3 determines whether or not electronic data can be given to the user application 2 based on the policy. A file acquisition request is made (step S54). Upon receiving this request, the DB / file server 4 transmits the corresponding file (step S55).

  The electronic data management server 3 makes a public key / private key / electronic certificate creation request to the certificate issuance / management server 6 (step S56). Upon receiving this request, the certificate issuance / management server 6 creates a public key, a private key, and an electronic certificate, and transmits them to the electronic data management server 3 (step S57). The electronic certificate and key pair (public key / private key) may be created for each user or for each file. The electronic data management server 3 encrypts the electronic data with the created public key, encrypts the private key with the user's public key (step S58), and uses the created electronic certificate and electronic data as the key / electronic data management server. 9 is registered (step S59).

  When the registration is completed, the key / electronic data management server 9 replies to the electronic data management server 3 (step S60).

  Subsequently, the electronic data management server 3 transmits the electronic certificate of the created public key, the encrypted electronic data, and the encrypted private key to the user application 2 (Step S61). The user application 2 inquires the certificate validity verification server 7 to verify the validity of the electronic certificate created when acquiring these and the user electronic certificate (step S62). The certificate validity verification server 7 transmits the verification result to the user application 2 side (step S63). As a result of the verification, if the user's electronic certificate has not expired, the user application 2 decrypts the encrypted private key (step S64), and decrypts the electronic data with the decrypted private key. (Step S65), thus, the use of electronic data is started (step S66).

  As described above, according to the fourth embodiment of the present invention, since only a user has a secret key for decrypting encrypted electronic data, security is further improved. In addition, when the user's electronic certificate has expired, the application 2 does not decrypt the encrypted electronic data. For example, even if a retired user tries to view the electronic data after retirement, If the electronic certificate is revoked, it can be disabled. Furthermore, registration of the created electronic certificate and electronic data ID can be received by the key / electronic data management server 9 and managed centrally.

  Next, a fifth embodiment of the present invention will be described.

  Since the basic configuration is the same as that in FIG. 5, the same components as those in FIG.

Hereinafter, a series of operations by the communication control system according to the fifth embodiment of the present invention will be described in detail with reference to the flowchart of FIG.
When an electronic data discard request is made to the electronic data management server 3 by the administrator (step S71), the electronic data management server 3 sends a corresponding electronic certificate acquisition request with the electronic data ID as a key to key / electronic data management. This is performed for the server 9 (step S72).

  The key / electronic data management server 9 transmits an electronic certificate corresponding to the ID to the electronic data management server 3 (step S73). Subsequently, the electronic data management server 3 makes an electronic certificate revocation request to the certificate issuance / management server 6 (step S74).

  Upon receiving this request, the certificate issuance / management server 6 notifies the certificate validity verification server 7 of the revocation (step S75) and notifies the electronic data management server 3 of the result (step S76). On the other hand, when an inquiry about the validity verification of the electronic certificate is made from the user application 2 to the certificate validity verification server 7 (step S77), the verification result is sent from the certificate validity verification server 7 to the user application 2. (Step S78). The user application 2 notifies that the electronic data has been discarded (step S109), and the encrypted electronic data is discarded (step S110).

  As described above, according to the fifth embodiment of the present invention, even if electronic data to be discarded is stored in an external storage medium such as a user's hard disk by an administrator, the electronic data is encrypted. It is possible to forcibly discard electronic data from the administrator side by obtaining an electronic certificate for the public key that is being used and revoking the electronic certificate. If the user's electronic certificate is to be revoked, the electronic data can be discarded on a user basis. The discarding of the electronic data is realized, for example, by deleting data stored in hardware or a medium (not shown) of the user terminal 1 in which the user application 2 is mounted, mixing noise, or the like.

  Further, instead of forcibly discarding, it is possible to make it impossible to decrypt the encrypted information or make it impossible to save the decrypted electronic data.

  The embodiment of the present invention has been described above, but the present invention is not limited to this, and it is needless to say that various improvements and changes can be made without departing from the spirit of the present invention. For example, the encryption method is not limited to the above.

It is a figure which shows the structure of the communication control system which concerns on the 1st-3rd embodiment of this invention. It is a flowchart explaining in detail a series of operations by the communication control system according to the first embodiment of the present invention. It is a flowchart explaining in detail a series of operation | movement by the communication control system which concerns on the 2nd Embodiment of this invention. It is a flowchart explaining in detail a series of operation | movement by the communication control system which concerns on the 3rd Embodiment of this invention. It is a figure which shows the structure of the communication control system which concerns on 4th, 5th embodiment of this invention. It is a flowchart explaining a series of operation | movement by the communication control system which concerns on the 4th Embodiment of this invention in detail. It is a flowchart explaining in detail a series of operation | movement by the communication control system which concerns on the 5th Embodiment of this invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... User terminal, 2 ... User application, 3 ... Electronic data management server, 4 ... DB / file server, 5 ... Policy server, 6 ... Certificate issuing / management server, 7 ... Certificate validity verification server, 8 ... Network.

Claims (6)

In a communication control system capable of communicating with a user terminal equipped with a user application,
A policy server that manages policies for each user;
A file server that stores electronic data;
When an electronic data acquisition request is received from the user terminal, a policy acquisition request is made to the policy server, and it is determined whether or not electronic data can be distributed to the user terminal based on the policy obtained from the policy server. A management server that controls to obtain electronic data from a file server and control the electronic data to be transmitted to the user terminal after encryption,
A communication control system comprising:   A certificate validity verification server for verifying the validity of the user's electronic certificate is further included. The certificate validity verification server receives the user's electronic certificate sent from the user terminal, and receives the electronic certificate. The communication control system according to claim 1, further comprising prompting the user application to discard the electronic data when the electronic certificate is revoked as a result of verifying validity of the certificate. .   The communication control system according to claim 2, wherein the discarding prohibits the decryption of the encrypted electronic data.   The communication control system according to claim 2, wherein the validity of the electronic certificate of the user can be revoked by an administrator. The communication control system according to claim 2, further comprising: an electronic data management server that manages an ID of electronic data distributed to a user and an electronic certificate of a key used to encrypt the electronic data. . The communication control system according to claim 1, further comprising an interface that accepts discarding of electronic data in units of electronic data or in units of users in the management server according to claim 1.

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