JPS61173545A - Document transmission system - Google Patents

Abstract

PURPOSE:To send output data only to one specified output device by generating information enciphered corresponding to the specific terminal and a deciphering key signal when information is outputted to the terminal, and deciphering the enciphered information at the specified terminal and outputting a document. CONSTITUTION:A terminal 1 informs a node 27 of a DES system key K for communication by an open key enciphering system and sends a control signal A which is sent by a conventional enciphering system. A node 23 receiving the reports deciphers the DES system key by using an RSA system enciphering key 35 and sends it to a node 24. The transmitted key is decoded by using the RSA system decoding key to obtain the DES system key K. The node 23 confirms that the DES system key K arrives correctly and a code message obtained by enciphering a secret document by the DES system through a conventional enciphering device by using the key K is transmitted. The node 24 deciphers the code message by using the DES system key K obtained as mentioned above to obtain the secret document, which is transmitted to a terminal 22. A terminal 2 outputs the data to an output device 24.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a method for transmitting and outputting documents that require security protection during output in an information transmission system having a plurality of terminals.

Conventional technology In the past, when sending and receiving documents that required confidentiality protection, the data on the transmission path was encrypted to protect the confidentiality of the data during transmission, but no measures were taken to protect the output of the transmitted document. 0 For example, in a system configuration like the one shown in Figure 4, the node section usually encrypts and encrypts the transmitted data.
The decoding was performed only when it was specified, and the output device was put away.

In FIG. 4, 21.22 is a terminal that performs communication control/processing and message output control/processing, 25.26 is an output device of the terminal 22, 23.24 is a node, and 27 is an optical fiber. Part of a network transmission path such as a coaxial cable is shown. Further, FIG. 3 is a diagram showing transmission of "communication by MIX method" which is one method of encrypted communication in data communication, and the same numbers as in FIG. 2 indicate the same things.

In Fig. 5, 3.1.32 is a conventional cryptographic device that performs DES encryption, 33.34 is a public key cryptographic device that performs R3A encryption, and 301 is the flow of transmitted messages, 31.1°. 3
12 is a flow of an encryption key (hereinafter referred to as "key K") used for encryption and decryption using a conventional cryptographic device, 302 is a flow of transmitted messages encrypted with key K, and 303 is an I! The original transmitted message flow decoded by K, 312 is R3
The flow of the key encrypted by the A method encryption key KE35 is shown. 〇The terminal 21 is connected to the output device 2 of the terminal 22.
5, when outputting a confidential document that requires integrity, the terminal 21 creates a DES key K for encrypting the confidential document and transmits it to the node 23. At node 23,
The DES key K is encrypted using the R3A encryption key 35 and transmitted to the node 24. R3 at node 24
The transmitted key is decrypted using the decryption key 36 of the A method, and a key K of the DES method is obtained. At node 23, DES
After confirming that the key K of the system has arrived correctly, the encrypted text obtained by encrypting the confidential document using the key K using the DES method using a conventional cryptographic device is transmitted. The node 24 decrypts the ciphertext using the DES key K obtained earlier,
A confidential document is obtained and sent to the terminal 22. Then node 2
3.24 also erases the DES key 31. Terminal 22
outputs this received message to the output device 25. At this time, multiple outputs of the same document can be made by connecting multiple output devices of the same type, such as the terminal 22. As described above, various methods have been used to protect the confidentiality of documents during transmission, but these methods have the drawback of impairing the integrity of document output.

Problems to be Solved by the Invention With such conventional methods, even though the originality of confidential information on the transmission path is protected in the transmission output of certificates, etc., the integrity of the output document is not guaranteed. If multiple output devices with the same function are connected, they can be output at any time, but the problem is that the originality cannot be guaranteed, which can lead to an unnecessary flood of identical documents. .

The present invention has been made in view of this point, and an object of the present invention is to realize a reliable document transmission output.

Means for Solving the Problems In order to solve the above problems, the present invention provides a document output device with a cryptographic processing device that performs the following operations based on two types of signals, so that the document can be output to only one specified output device. It is configured to output data.

■ Randomly generates a key for encrypting an output document to the output information providing terminal, transmits it to the output information providing terminal, and decrypts the output text encrypted with the randomly generated encryption key. Yes 0 ■ Cancels decryption processing.

Effects The present invention uses the above-described configuration to perform uniform transmission and output of documents such as certificates, and eliminates the effect that even if the sending side attempts to output information to multiple output devices at the same time, it cannot be performed. be. Therefore, unnecessary overflow of the same document can be prevented.Embodiment 0 FIG. 1 is a block diagram showing an example of the configuration of an output device of the present invention. In FIG. 1, 1 is an output data temporary storage buffer 1, 2 is a cryptographic processing device, 3 is an output control section, 4 is an output processing section, and 5 is a transmission processing section.

FIG. 2 is a block diagram of one configuration of the cryptographic processing device 2 in FIG. 1. In FIG. 2, 41 is a signal determination section, 45 is an encryption key generation processing section, 43 is an encryption key storage section, 44 is a decryption processing section, and 45 is a time monitoring section. The operation of the system according to the embodiment of the present invention will be explained using FIGS. 1 and 2.

The signal determination unit 41 in the cryptographic processing device determines two types of signals and controls the other processing units.
The cryptographic processing device uses the respective signals to perform the following operations.

(2) The operation signal determining unit 41 when determining “control signal A” outputs a control signal to the encryption key generation processing unit 42. The encryption key generation processing section 42 that has received it sends the randomly generated encryption key to the transmission processing section 5 and transmits it, and at the same time stores it in the encryption key storage section 43, and activates the decryption processing section 44. In the decoding processing unit 44, the control for canceling the decoding process is performed by the signal determination unit 41 or the time monitoring unit 46.
The decryption process is performed until the data is sent from.

(2) The operation signal determining section 41 when determining "control signal B" sends control to cancel the decoding process to the decoding processing section 44.

Regarding data other than these signals, the signal determination unit 41
And the decoding processing unit 44 passes the data without any control or processing. In addition, the time monitoring unit 45 also uses the signal determination unit 4
1 to the decoding processing unit 44, and if the data is interrupted for a certain period of time or more, the decoding processing unit 44 is controlled to cancel the decoding process. ' Figure 3 shows the exchange between the terminal, mate, and output device when transmitting and outputting a document that requires uniformity using the output device shown above, and Figures 1, 2, and 3 Show one page of this using a diagram. The numbers in parentheses below indicate the numbers in Figure 3.

When there is a document request from the terminal 2 and the terminal 1 sends the requested document, the "MIX communication" shown in FIG. 5 is performed between the nodes. First, the terminal 1 notifies the node 27 of the key K of the DES system for communication using the public key cryptosystem (1), and also notifies the node 27 of the control signal A to be sent using the conventional cryptosystem (2). Upon receiving this notification, the node 23 encrypts the DES key K using the R5A encryption key 36 and sends it to the node 24 <3>.

The transmitted key is decrypted using the R3A decryption key 36 to obtain the DES key K. D at node 23
After confirming that the key K of the ES method has arrived correctly (4), the secret document is encrypted using the key K using the DES method, and the encrypted text is transmitted using a conventional cryptographic device.5 〉. The node 24 decrypts the ciphertext using the DES key K obtained earlier, obtains a confidential document, and sends it to the terminal 22 <6>
. The terminal 2 outputs the data to the output device 24<7
〉.

The cryptographic processing device 2 of the output device 24 that received the data detects the control signal A and performs the processing shown in (2) above. The terminal 22 that has received the response data sends the encryption key and response data to the node 24 for the same security protection on the transmission path as the previous terminal 21 <9.10>. After confirming the key distribution (11, 12), the node 24 sends the encrypted response data (encryption key information) to the node 23 (13).
〉Send to terminal 21〉14〉0 Terminal 21 obtains an encryption key for output device 24 from the received response data and sends an output message encrypted based on the key to node 27〉15〉. In the following, regarding transmission, the above-mentioned (-MIX communication) is performed, but the flow is omitted. The node 23 encrypts the output message and sends the output message to the node 24 (16). Decrypt the text and send it to the terminal 22
Send to <17>, terminal 22 sends to output device 24 1
8>0 The terminal device 24 outputs the message according to the process (■), and sends a notification of output completion to the terminal 21<19.20, 21
．． 22>. After the output is finished, the terminal 21 sends a signal to the output device 24 for canceling the decryption process of the encryption device of the output device 24.
Send to (23, 24, 25.26). The output device 24 that has received the control signal for canceling the decoding process cancels the decoding process of the decoding processing section <27.28, 29.30>.

As a result of the above, for example, even if a plurality of output devices having the same configuration are connected to the terminal 22, the decryption key has been changed, so that the data will not be correctly output to other output devices.

Effects of the Invention By providing a document output device with a cryptographic processing device that performs the following operations using two types of signals, output data can be output to only one output device, which enables uniform transmission of documents such as certificates. It performs output.

■ A key for encrypting the output document to the output information providing terminal is randomly generated and sent to the output information providing terminal, and the output text encrypted with the randomly generated encryption key is decrypted. Yes 0 ■ Cancels decryption processing.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an example of the configuration of the document transmission system of the present invention, FIG. 2 is a block diagram showing the configuration of the cryptographic processing device of the system 4, and FIG. Figure 4 is a diagram illustrating an example of the communication between terminals, nodes, and output devices at the time of communication; Figure 4 is a configuration diagram of the terminal arrangement in the network according to the present invention; Figure 6 is an example of encrypted communication in data communication. FIG. 2 is a diagram illustrating the configuration of one type of transmission, ie, "communication using the MIX method." 1... Output data temporary storage buffer, 2...
. . . Cryptographic processing device, 3 . . . Output control unit, 4.
...Output processing section, 6...Transmission processing section,
21.22...Communication terminal, 2°3.24...
...Node, 25.26...Storage device, 27
. . . Transmission path, 41 to 45 . . . Control signal data, 31. 32 . . . Conventional encryption device, 33.
34...Public key cryptographic device, 301 is the flow of transmitted messages. Name of agent: Patent attorney Toshio Nakao and 1 other person No. 1
Figure 2 Figure 3 Figure 4

Claims (4)

[Claims] (1) Any terminal has at least a cryptographic processing device that is activated by a terminal designation signal from another terminal, and when outputting information to another terminal, it can encrypt and decrypt information corresponding to the specific terminal. A document transmission system characterized by generating a key signal, activating the cryptographic processing device with the decryption key signal up to a designated terminal, decrypting the encrypted information, and outputting a document. (2) The cryptographic processing device includes a response processing unit that transmits a key for encrypting an output document to a terminal using two types of signals, and a decryption processing unit that decrypts and decrypts the output text. A document transmission system according to claim 1, characterized in that the document transmission system comprises: (3) The document transmission system according to claim 1, wherein the response processing section randomly generates a key for encryption. (4) The decoding processing unit is provided with a timer that monitors the time when the signal for canceling the decoding process stops, and the decoding process is canceled according to the monitoring time. document transmission system.