JPH03211932A - Communication control method for data terminal equipment - Google Patents

Abstract

PURPOSE:To facilitate operations by eliminating the need for setting the key of telephone communication, etc., between a host and a terminal by executing batch control to the keys on a host side and a terminal side by the host side and automatically sending the key to be used by the terminal side from the host to the terminal at the time of log-ON from the terminal. CONSTITUTION:The side of a host 1 executes the batch control to the keys to be used on the host 1 side and a terminal 11 side, and a means 3 is provided to automatically send the key to be used on the terminal 11 side form the host 1 to the terminal 11 at the time of log-ON from the terminal 11, to set the key and to update the key to be used on the host 1 side and the terminal 11 at every time. Thus, it is not necessary for the terminal 11 to set and control the key and the operation on the terminal 11 side is simplified. Further, by updating the keys on the host 1 side and the terminal 11 side every time, secrecy protection and safety can be secured.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention aims to improve the operability of the terminal side and maintain the conventional security when connecting a terminal device to a host computer via a communication line and performing encrypted communication. , regarding how to ensure safety.

[Conventional technology]

Conventionally, when a terminal device and a host computer are connected via a communication line and a cipher is used for communication, it has been necessary to synchronize and set the keys necessary for the cipher on both the host side and the terminal side through telephone contact or the like.

The related technology is Japanese Patent Application Laid-Open No. 63-299546.
The number is mentioned.

[Problem to be solved by the invention]

In order to connect a terminal device and a host computer via a communication line and perform encrypted communication, in the conventional method, the host side and the terminal side contact each other by telephone, etc., and mutually set and use the keys necessary for encryption. was.

It is an object of the present invention to provide a means that eliminates the trouble of key setting by telephone contact, etc., and ensures security and security as before.

[Means to solve the problem]

In order to achieve the above purpose, the host side centrally manages the keys used by the host side and the terminal side, and the key used by the terminal side is automatically sent from the host to the terminal when logging on from the terminal. Both sides and terminals now have a means to update the keys used.

[Effect]

The host side collectively manages the keys used by the host side and the terminal side, and when logging on from the terminal, the key used on the terminal side is sent from the host to the terminal and set, so that I! To simplify operation on a terminal side by eliminating stage setting and management. Also,
Confidentiality and safety are ensured by updating the keys on the host and terminal sides each time (every time you log on).

〔Example〕

Hereinafter, one embodiment of the present invention will be described with reference to the drawings.

FIG. 1 shows an example of the configuration of the present invention, in which 1 is a host computer;
2 is a communication control unit, 3 is a host control unit, 4 is a random number generation unit,
5 is an exclusive OR, and 6 is a management table.

The management table contains user IDUs corresponding to user number i.
i, host side key data hki, terminal side key data tki,
This is a table composed of passwords Pi. Each key data is initialized to a different value for each user number i.

In FIG. 1, 11 is a terminal device, 12 is a communication control section, 13 is a terminal control section, 14 is a random number generation section, 15 is an exclusive OR, 1
6 is a display device (CRT), and 17 is an input device (keyboard).

Note that the key data is # (key) necessary for the random number generation section to generate random numbers.6 The host computer and the terminal device are connected one-to-one through a communication line 20.

The operation of the terminal control section 13 will be explained with reference to the flowchart shown in FIG.

The terminal control section first initializes the key data of the random number generation section, and then, when the user ``D'' is input from the keyboard 17, the terminal control section transmits the user ID to the host.

When a password input request message is received from the host, it is checked to see if the message contains terminal-side key data. If terminal-side key data is included, the key data is separated from this message and the random number generator Set as key.

If terminal side key data is not included, the key of the random number generator remains in the initialized state.

Next, a password input request message will be displayed on the display section (CRT).
Output to 16.

When a password Pn is input from the keyboard in response to a password input request message, the random number generated from the random number generator and the password are exclusive-ORed and encrypted using the previously set terminal-side key data, and then sent to the host.

When an encrypted response is received from the host, it is exclusive-ORed with the random number generated from the random number generator, decrypted, and sent to CR.
Output to T.

If the response is a permission response, communication is continued; if the response is a non-permission response, the key of the random number generator is initialized and the process returns to user ID input.

The operation of the host controller 3 will be explained with reference to the flowchart in FIG.

When the host control unit receives the user IDUn from the terminal device, it obtains terminal-side key data corresponding to the user ID from the management table 6, adds it to a password input request message, and sends it to the terminal device. In addition, if there is no terminal side key data,
Only the password input request message is sent to the terminal device.

Next, the host-side key data corresponding to the user ID from the management table is set as the key of the random number generator, and the host-side and terminal-side key data in the management table are updated.

If there is no host-side key data, the key in the random number generator remains in its initialized state.

When the encrypted password is received from the terminal device, it is decrypted by exclusive ORing with the random number generated from the random number generator using the previously set host-side key data.

Next, obtain the password corresponding to the user ID from the management table, compare it with the password received from the terminal, and if they match, a permission response will be sent. If they do not match, a denial response will be sent. , encrypt it, and send it to the terminal.

If permission is not granted, the key data of the random number generator is initialized and the system waits for activation from the terminal.

Even if the key data is stolen, there is no problem because the host-side and terminal-side key data in the management table are updated regardless of whether permission is granted or not.

Next, FIG. 4 shows an ESC sequence showing the key data in the password input request message.

ESC and TK indicate the number of terminal lock data, Q indicates the terminal side lock data length, and after that there is terminal side key data.

Even if the key data in the password input request message is stolen, the 5 key data will not be usable from the next time onwards as it will have been updated. Furthermore, even if the password encrypted using the key data is stolen, the value will change from the next time onwards, so it cannot be used.

〔Effect of the invention〕

According to the present invention, the host side collectively manages not only the host side keys but also the terminal side keys, and the key used by the terminal side when logging on from the terminal is automatically sent from the host to the terminal. You can eliminate # setting by telephone contact etc. In addition, data confidentiality and safety can be ensured by encrypting all data from the password to the end of communication and updating the keys on the host and terminal sides each time (every time you log on).

[Brief explanation of drawings]

FIG. 1 is a block diagram of an embodiment of the present invention, FIG. 2 is a flowchart showing the operation of the terminal control section in FIG. 1, and FIG.
FIG. 4 is a flowchart showing the operation of the host control unit shown in FIG. 4, and FIG. 4 is a format diagram of key data included in a password input request message. DESCRIPTION OF SYMBOLS 1...Host computer, 2.12...Communication control unit, 3...Host control unit, 4.14...Random number generation unit, 5.15...Exclusive OR, 6... Management table, 11... Terminal device, 13... Terminal control unit, 16... Display device 1 (CRT), 躬躬 3 SC: SK Accor F. K: Sister blq! 1ylt device identification code.ノ; Length of strength and strength

Claims (1)

[Claims] 1. In a communication control method in which when a terminal device and a host computer are connected via a communication line and communication is performed using encryption, the host side and the terminal side synchronize, set an encryption key, and encrypt.
The host side centrally manages the keys used by the host side and the terminal side, and when logging on from the terminal, the key used by the terminal side is automatically sent from the host to the terminal and set, and the keys on the host side and terminal side are updated every time. 1. A communication control method for a data terminal device, comprising: means for controlling communication of a data terminal device.