JPH0563681A - Device for preventing leakage of secrecy in information transmission - Google Patents

Abstract

PURPOSE:To prevent leakage of secrecy for extra insurance by eliminating a care about leakage of secrecy due to mis-operation such as a specific button switch left undepressed. CONSTITUTION:In a secrecy leakage prevention device in which a ciphering device 5 is provided to a route of a sender side when viewing from a transmission reception terminal equipment 1 as a device connecting the transmission reception terminal equipment and a line network and a ciphering decoder 6 is provided to a route of a receiver side, the input side of the ciphering device 5 is provided with a switching means 7 which is normally thrown to the position of the ciphering device and which is selected to bypass the ciphering device 5 through the release of connection to the ciphering device 5 by a specific operation, and the input side of the ciphering decoder 6 is provided with a switching means 8 which is thrown to the position of the ciphering decoder 6 when the information given to the input of the ciphering decoder 6 is ciphered and which is selected to bypass the ciphering decoder 6 when the information is not ciphered.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a confidential information leakage prevention device for transmitting and receiving information from a transmitting / receiving terminal using a public network such as a public network.

[0002]

2. Description of the Related Art At present, in an advanced information society, many important (confidential) information is routinely transmitted and received via a communication network. Examples are conversational communication by telephone, transmission by facsimile, and computer communication.

In communication using a dedicated line such as an in-house information communication network in such a communication network, since the other party is fixed, almost all information is also provided by security functions such as ID code management and password management. This can be prevented.

On the other hand, public network (analog, digital)
When information communication is performed using, the ID code management and the password management are not sufficient, and countermeasures against confidentiality leakage and theft are also required. Furthermore, when using a public line network, it is necessary to take measures against erroneous transmission due to an operation error.

As an example, when a secret drawing or document is transmitted by facsimile using a public telephone network of a telephone,
It has been attempted to make a mistake by registering the destination telephone number with speed dial or the like, but erroneous operation due to a mistake in pressing the speed dial button is unavoidable.

[0006] In recent years, as a countermeasure against confidentiality leakage, an encryption device that processes and scrambles the original information by various encryption methods, and a descrambler of the processed information by the key of the encryption method, An encryption / decryption device has been developed that returns the information to.

[0007]

However, a security leakage prevention device incorporating the above-mentioned encryption device or encryption / decryption device, which is being implemented by NTT (Nippon Telegraph and Telephone Corporation), etc.
Information to be sent is always encrypted, or is encrypted only after a specific operation such as pressing a specific switch.

Therefore, if the information to be sent is always encrypted, the receiving side must have a receiving device having an encryption / decryption device, and the destination is limited. In addition, in the case of encryption that is performed only after a specific operation such as pressing a specific switch, if this switch operation is forgotten, information will be sent without being encrypted, which is not useful for preventing confidentiality leakage.

An object of the present invention is to eliminate the inconvenience of the conventional example, to eliminate the fear of confidential information leakage due to an operation error, and to provide a confidential information leakage prevention apparatus for information transmission.

[0010]

In order to achieve the above object, the present invention provides an encryption device as a device for connecting a transmission / reception terminal and a line network to the route of the transmission side as seen from the transmission / reception terminal, and In a confidentiality leak prevention device where an encryption / decryption device is installed at the root, always connect to the encryption device on the input side of this encryption device, and release the connection to this encryption device by a specific operation By providing switching means for switching to bypass, if the information received at the input side of the encryption / decryption device is encrypted, connect to the encryption / decryption device, and if it is not encrypted, decryption The gist is that a switching means for switching the device is provided.

[0011]

According to the present invention, the switching means is connected to the encryption device unless the specific operation such as pressing the specific switch is performed when transmitting from the transmitting / receiving terminal, and the transmitted information is transmitted to the encryption device. Scrambled with. Further, when transmitting information that does not require confidentiality leakage prevention, when a specific operation such as pressing a specific switch is performed, the switching means is switched and the transmitted information can be sent out as it is, bypassing the encryption device. In this way, the confidentiality is maintained because the encryption is performed even if the specific operation is forgotten.

On the other hand, in the transmitting / receiving terminal which receives information,
When the transmitted information is encrypted, it is detected and the switching means connects to the encryption / decryption device, descrambles and outputs it. If it is not encrypted, it is detected and the switching means switches to bypass the encryption / decryption device and output as it is.

With the above configuration, not only when transmitting / receiving between the transmitting / receiving terminals equipped with the security leakage prevention device of the present invention, but also including the transmission / reception terminal equipped with the security leakage prevention device of the present invention. Transmission / reception with a transmitting / receiving terminal that does not exist is performed without any support, and if you forget the specific operation such as pressing a specific switch and send to a transmitting / receiving terminal that is not equipped with the confidentiality leakage prevention device of the present invention, encrypted information is output. There is no risk of confidential information leakage because it is only done.

[0014]

Embodiments of the present invention will now be described in detail with reference to the drawings. FIG. 1 is a block diagram of a confidential information leakage prevention apparatus for information transmission according to the present invention. As an apparatus for connecting a transmission / reception terminal 1 and a public line network 2, an interface circuit 3 on the transmission / reception terminal 1 side and an interface circuit on the public line network 2 side. 4, an encryption device (scrambler) 5 is provided on the transmission side route as viewed from the transmission / reception terminal 1, and an encryption / decryption device (descrambler) 6 is provided on the reception side route.

The encryption device 5 processes the original information (data) by various encryption methods and scrambles it, and the encryption / decryption device 6 processes the processed information (data) by the above-mentioned encryption. The data is descrambled with the key of the encryption method to restore the original information (data). Figure 4
The configuration of the encryption device 5 and the encryption / decryption device 6 is shown in Fig. 7. The output from the encryption key / decryption key 12 is introduced into the key processing unit 11, and the output from this key processing unit 11 is used for preprocessing → The process of data agitation processing → data agitation processing → post-processing is performed.

The interface circuits 3 and 4 are CCITs.
V interface, X interface, I interface which is a standard of T (International Telegraph and Telephone Consultative Committee), GP-IB which is a standard of IEEE (Institute of Electrical and Electronics Engineers), and EIA (American Electronics Industry Association) standard. R
The S-232C and the Y interface, which is a standard of NTT (Nippon Telegraph and Telephone Corporation), may be used properly depending on the network and terminal to which the connection is made.

The input side of the encryption device 5 is normally connected to the encryption device 5, and the connection to the encryption device 5 is released by a specific operation such as a push button switch to bypass the encryption device 5. The switching means 7 is provided by a switch or the like.

If the received information is encrypted on the input side of the encryption / decryption device 6, it is connected to the encryption / decryption device 6, and if it is not encrypted, the encryption / decryption device 6 is connected.
The switching means 8 is provided by a switch or the like for switching so as to bypass. The encryption device 5, the encryption / decryption device 6 and the switching means 7 and 8 are composed of a CPU (central processing unit) 9
And the CPU 9 is connected to a storage device (memory).
10 are connected. The CPU 9 is provided with a discriminating means for automatically discriminating whether or not the information inputted to the switching means 8 is encrypted and for issuing a command signal for switching the switching means 8. If the received information is a digital signal, this discriminating means makes the determination based on some bits of the head.

Next, the usage will be described. FIG. 2 shows a transmission flow in the case of facsimile communication. The dial of the other party is turned, and if the other party does not have the device of the present invention, the through button as a specific switch is pushed and then the send button is pushed. As a result, the switching means 7 operates to bypass the encryption device 5 and the transmission is performed as it is.

When the other party has the device of the present invention, the send button is pressed as it is. The switching means 7 connects the interface circuit 3 and the encryption device 5, and the information is encrypted by the encryption device 5.
Will be encrypted and sent.

FIG. 3 shows an incoming call flow. When the incoming information is encrypted, the switching means detects it and connects to the encryption / decryption device 6 to descramble (explain) it. To receive. If it is not encrypted, it is detected and the switching means 8 switches to bypass the encryption / decryption device 6 and receive the data as it is.

The communication partner may be registered and set in advance by using the optional function, and the communication partner may be first confirmed before each communication. In this case, if the other party is not registered, the communication is stopped.

[0023]

As described above, the confidential information leakage prevention device for information transmission according to the present invention eliminates the fear of confidential information leakage due to operation mistakes such as forgetting to press a specific button switch, and ensures complete security leakage prevention. It is possible.

[Brief description of drawings]

FIG. 1 is a block diagram showing an embodiment of a confidential information leakage prevention device for information transmission according to the present invention.

FIG. 2 is a flowchart showing an operation during transmission.

FIG. 3 is a flowchart showing an operation when an incoming call arrives.

FIG. 4 is an explanatory diagram of an encryption device and an encryption decryption device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Transmission / reception terminal 2 ... Public line network 3, 4 ... Interface circuit 5 ... Encryption device 6 ... Encryption / decryption device 7, 8 ... Switching means 9 ... CPU 10 ... Storage device 11 ... Key processing device 12 ... Cryptographic key / decryption key

Claims (1)

[Claims] 1. A security leakage prevention device, comprising an encryption device provided on a route of a transmission side as seen from the transmission / reception terminal and an encryption decryption device provided on a route of a reception side as a device for connecting a transmission / reception terminal to a network. , The input side of this encryption device is provided with switching means for connecting to the encryption device at all times, and switching to bypass the encryption device by disconnecting the connection to this encryption device by a specific operation. If the information received at the input side of the decryption device is encrypted, it is connected to the encryption decryption device, and if it is not encrypted, switching means is provided to switch to bypass the encryption decryption device. Special information leakage prevention device for information transmission.