JPH0123787B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Summary] A data storage method that improves confidentiality by updating an encryption code given when storing data in a data storage unit according to given conditions.

[Industrial application field]

The present invention relates to a data storage system, and particularly to a data storage system in which an encryption code is attached to data to be stored in order to maintain confidentiality.

[Conventional technology]

Information stored in a database can be quickly obtained using a search system, but it is important to prevent information that should be kept confidential from being obtained by a third party using such a search system. There is a need to.

For this reason, in the past, information that should be kept secret was encrypted to make it difficult for anyone other than a specific person to search for this information.

FIG. 5 is a diagram explaining the conventional data storage method, in which when data (1, 58123456) as shown in FIG. An encryption code AA corresponding to this identification code K3 is assigned to the data storage unit D.
Store in.

When the data (2, 5973162) is inputted with the identification code K4, the encryption unit N adds an encryption code BB corresponding to K4 to this data and stores it in the data storage unit D.

Therefore, a third party can access the information (1, 58123456): AA, (2,
5973162): Even if BB is known, it becomes difficult to decipher what AA and BB mean, and the purpose of keeping information confidential is achieved for the time being.

[Problem that the invention seeks to solve]

However, with this data storage method, once a third party learns the meaning of the code used for encryption, all the information stored in the data storage unit that should be kept secret cannot be read. There is a concern that

The present invention has been made in view of this point, and an object of the present invention is to provide a data storage method that can more reliably maintain confidentiality.

[Means for solving problems]

FIG. 1 shows a principle block diagram of the data storage system of the present invention.

I is a phase pattern table, T is each phase 1,
Corresponding to 2, 3, . A basic phase control device that sets one bit to "1", A is a database update encryption device, M is a data input/output encryption device, P is a data input/output section,
D is a data storage section in which data input from the data input/output section P is stored.

[Effect]

Under the control of the basic phase control device H, the phase data of the conversion phase device T is updated according to predetermined conditions such as the number of accesses to the data storage section D, date, and time.

That is, the flag bit of the conversion phase shifter T is set from "0" to "1".

The encryption code attached to the data in the data storage section D is also updated to a new encryption code corresponding to the updated phase data. The database update encryption device A updates the encryption code added to this data.

The database update encryption device A adds an encryption code in the phase pattern table corresponding to the valid phase to the data stored in the data storage section D.

The data input/output encryption device M converts the identification code input from the data input/output section P into an encryption code by referring to the flag bit and phase pattern table I of the conversion phase device T, and conversely converts the identification code input from the data input/output section P into an encryption code. D
A phase device T converts the encryption code attached to the data of
The identification code is converted into an identification code corresponding to the valid bits in the data storage section D, and this identification code is given to the data retrieved from the data storage section D.

〔Example〕

Embodiments of the present invention will be described in detail below with reference to the drawings. FIG. 2 is a configuration diagram of an embodiment of the present invention, in which parts equivalent to those in FIG. 1 are given the same reference numerals. Q is a keyboard, and R is a memory that stores the phase pattern table I. G is a display section. Data to be stored in the data storage section D is inputted from the keyboard Q.

This data is, for example, as shown in FIG. 3a, where the identification codes K3, K4, K1, .
57486102)... indicates the order of importance. When this identification code is input from the keyboard Q, it is converted into an encrypted code by the data input/output encryption device M as follows.

Referring to the flag bit of the conversion phaser T,
Since phase “1” is found to be valid, next phase pattern table I in storage unit R (Fig. 4)
, and the encryption codes AA, AB, AC, and AD in the phase "1" column of Table I are assigned according to the identification code of the input data.

For example, if the identification code attached to the input data (1, 58123456) is K3, this input data is stored in the data storage section D with the encryption code AC attached.

FIG. 3b schematically shows the data stored in this way.

When searching for information, an identification code, for example K1, is input using the keyboard.

The data input/output encryption device M knows the phase in which the flag bit of the conversion phase device T is “1”, and based on this phase, the phase pattern table I
Find the encryption code corresponding to the identification code inside.

In the conversion phase device T, when the flag bit corresponding to the phase “1” is “1”, the identification code K
Since the encryption code corresponding to 1 is AA, the data input/output encryption device M reads out all the data to which the encryption code AA has been added in the data storage section D.
Next, an identification code K1 corresponding to the encryption code AA is added to these read data and output to the display section G. In this way, the search for the data labeled with the identification code K1 is completed.

The basic phase control device H updates the phase data of the conversion phase device T according to predetermined update conditions (date and time, number of accesses to the data storage section D, etc.).

Therefore, the phase whose flag bit in the conversion phase shifter T is newly set to "1" becomes valid. This phase data may be updated by adding "1" to the old phase. Then, from the basic phase control device H to the database update encryption device A
The old and new phase data before and after updating are transferred to.

When the new and old phase data are input, the database update encryption device A refers to the phase pattern table I and sets the encryption codes AA, AB, which correspond to the old phase "1" attached to the data in the data storage section D. A.C.
The encryption code BA corresponding to the new phase “2”,
Change to BB, BC. At this time, since the number of data with the identification code K4 is considerably larger than the number of data with other identification codes, the encryption code is not changed in conjunction with the change of the phase data.

Therefore, the task of changing the encryption code when updating the phase data by the basic phase control device H becomes relatively simple. As a result, the data to which the identification code K4 is attached remains attached with the encryption code assigned when it is stored in the data storage section D.

When searching for data with identification code K4, when identification code K4 is input from keyboard Q,
In the data input/output encryption device M, not only the encryption code corresponding to the phase in which the flag bit in the conversion phase shifter T is "1" at the time of retrieval, but also all the encryption codes AD, corresponding to the identification code K4,
Search for data marked with BD, CD, etc.

When performing a search, the data input/output encryption device M does not use each encryption code as a search key, but uses all encryption codes other than the encryption codes corresponding to K1, K2, and K3 as a search key. used as

For example, when the effective phase is "2", when searching for the identification code K4, the search key is expressed as ++ (where "+" indicates sum logic, and the bar symbol indicates NOT (equals)).

By using such a logical conditional expression as a search key, a faster search is possible than using each encryption code one by one as a search key.

〔Effect of the invention〕

In this way, in the data storage method according to the present invention, the encryption code used for confidentiality is updated, so there is no chance that the data with the encryption code stored in the data storage unit will be accidentally revealed to a third party. Even if the acquired data is obtained, the third party will recognize it as different data after the encryption code is updated, making it difficult to decipher the acquired data, which is highly effective in maintaining data confidentiality. .

[Brief explanation of drawings]

FIG. 1 is a diagram explaining the principle of the present invention, FIG. 2 is a configuration diagram of an embodiment of the present invention, FIGS. 3 a and b are diagrams showing data formats, and FIG. 4 is a diagram showing a phase pattern table.
FIG. 5 is a diagram showing a conventional data storage method. I: phase pattern table, T: conversion phase device, H: basic phase control device, A: database update control device, M: data input/output encryption device,
D: Data storage section.

Claims (1)

[Claims] 1. An input unit for inputting data with an identification code attached, converting the identification code of the input data into an encryption code, and converting the encryption code added to the data read from the data storage unit into an identification code. a phase pattern table obtained by assigning a phase to each of a plurality of encryption codes determined corresponding to the identification code; a conversion phase device that makes one phase valid; and a basic phase control device that updates the valid phase according to a given condition; A new encryption code corresponding to the phase is obtained from the phase pattern table, and the new encryption code is added to the data in place of the encryption code added to the data in the data storage unit. Characteristic data storage method.