KR101795482B1 - Device and method for encrypted data retrival - Google Patents

Abstract

The present invention includes a communication module, a memory in which a data retrieval program is stored, and a processor for executing the program. At this time, the processor calculates the index corresponding to the search target data among the data stored in the server, based on the range and the key, and transmits the calculated index to the server, And receives data. The range is calculated based on the permutation information received from the server, and the key is set corresponding to the data stored in the server.

Description

TECHNICAL FIELD [0001] The present invention relates to a data search terminal,

The present invention relates to a data search terminal and a search method thereof.

Common data retrieval techniques perform searches on unencrypted information. However, as the technology for storing data in a cloud environment develops, there is an increasing demand for searching for encrypted data.

The order preserving encryption (OPE) method encrypts data but preserves the order of the results. The sequential encryption method can satisfy both stability and retrieval efficiency through data encryption. However, there is a risk that data informa- tion can be leaked from the sequence because the sequence preservation encryption method preserves the order.

In this connection, Korean Patent Publication No. 1584220 (entitled "Encoding Method for Maintaining Encrypted Data Alignment") discloses a method for encoding encrypted data by counter mode block encryption so as to maintain a clear text data sort order Lt; / RTI >

Disclosure of Invention Technical Problem [8] The present invention is directed to a data retrieval terminal and a retrieval method for retrieving encrypted data stored in a server.

It should be understood, however, that the technical scope of the present invention is not limited to the above-described technical problems, and other technical problems may exist.

According to an aspect of the present invention, there is provided a terminal for retrieving data stored in a server according to the first aspect of the present invention includes a communication module, a memory in which a data retrieval program is stored, and a processor for executing the program. At this time, the processor calculates the index corresponding to the search target data among the data stored in the server, based on the range and the key, and transmits the calculated index to the server, And receives data. The range is calculated based on the permutation information received from the server, and the key is set corresponding to the data stored in the server.

According to a second aspect of the present invention, there is provided a method of retrieving data stored in a server in a terminal, comprising: calculating an index corresponding to data to be retrieved from data stored in a server based on a range and a key; Transmitting the calculated index to a server; And receiving data corresponding to the index calculated from the server. In this case, the range is calculated based on the permutation information received from the server, and the key is set corresponding to the data stored in the server.

The present invention can rearrange the data at the terminal, transmit the data to the server, and store the data in the database of the server. Therefore, the present invention can ensure the stability of data stored in the server. In addition, the present invention can perform an efficient search for encrypted data stored in a server through a binary search. Therefore, the present invention can prevent data leakage and provide quick retrieval of encrypted data.

1 is a block diagram of a data retrieval system in accordance with an embodiment of the present invention.
FIG. 2 is an exemplary diagram of a relational matrix and a balance matrix according to an embodiment of the present invention.
3 is an exemplary diagram of a data encryption matrix according to one embodiment of the present invention.
4 is an illustration of data according to an embodiment of the present invention.
5 is an exemplary diagram of data retrieval according to an embodiment of the present invention.
6 is a flowchart of a search method of a data search terminal according to an embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings, which will be readily apparent to those skilled in the art. The present invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. In order to clearly illustrate the present invention, parts not related to the description are omitted, and similar parts are denoted by like reference characters throughout the specification.

Throughout the specification, when a part is referred to as being "connected" to another part, it includes not only "directly connected" but also "electrically connected" with another part in between . Also, when a part is referred to as "including " an element, it does not exclude other elements unless specifically stated otherwise.

The following is a description of a data retrieval system 100 according to an embodiment of the present invention, with reference to Figs.

1 is a block diagram of a data retrieval system 100 in accordance with an embodiment of the present invention.

The data retrieval system 100 retrieves the encrypted data stored in the server 120 by the terminal 110. [ At this time, the data stored in the server 120 may be stored in the database 122 included in the server 120 after being encrypted by the terminal 110.

The data retrieval system 100 may include a server 120 and a plurality of terminals 110.

The server 120 may receive and store data from the terminal 110. The server 120 may also provide data corresponding to the request of the terminal 110 to the terminal 110 in response to a request from the terminal 110. [ The server 120 may include a database 122 capable of storing data.

At this time, the database 122 may be included in the server 120 in the form of an application program or a service. In addition, the database 122 may be a database server connected to the server 120. The server 120 may be a cloud server.

The server 120 may include permutation information that can be used by the terminal 110 for encryption. In this case, the permutation information may include a balanced matrix and a balanced matrix in which all rows of the matrix are permutations. The inference matrix and the balance matrix may be a square matrix having the same number of rows and columns.

FIG. 2 is an exemplary diagram of a relational matrix and a balance matrix according to an embodiment of the present invention.

The balance matrix means a matrix in which the same elements in the same column can not be duplicated at all, as shown in Fig. 2 (a). The equilibrium matrix can be denoted as "1-balanced matrix" or "1-balanced".

As shown in FIG. 2 (b), the relational matrix means a matrix including the same number of elements of the same column or less. The affine matrices can be denoted as " k - matrix" or " k - bounded" according to the same number of elements ( k ) contained in the column.

The terminal 110 encrypts the data and stores it in the server 120. The terminal 110 can retrieve the encrypted data stored in the server 120. The terminal 110 includes a communication module 111, a memory 112, and a processor 113.

The communication module 111 can perform data communication with the server 120.

The memory 112 stores a data retrieval program. At this time, the memory 112 collectively refers to a non-volatile storage device that keeps stored information even when no power is supplied, and a volatile storage device that requires power to maintain stored information.

The processor 113 may store the data in the database 122 included in the server 120. At this time, the processor 113 can rearrange the data to be stored and transmit the data to the server 120.

Specifically, the processor 113 stores the original data in the database 122 of the server 120. At this time, the raw data may be data sorted according to a specific property. For example, the raw data may be data sorted according to a primary key.

The processor 113 may select one of the permutation matrix and one or more balance matrices of the permutation information stored in the server 120 to store the raw data. At this time, the size of the selected population matrix and the balance matrix can be determined according to the number of raw data to be stored.

Also, in this specification, the indexes of the raw data, the relational matrix and the balance matrix can start from zero. That is, the index of the raw data is equal to or larger than 0 and can have a value smaller than 'raw data size - 1'. Also, the index of the row and the index of the column in the matrix are equal to or greater than 0, and may have a value smaller than the number of dimensions of the matrix - 1.

On the other hand, the processor 113 may select the number of dimensions of the relational matrix and the balance matrix such that the product of the dimensions of the relational matrix and the balance matrix is greater than the number of raw data. For example, if the number of primitive data is ten, the processor 113 may select the population matrix and the balance matrix such that the product of the number of dimensions of the population matrix and the balance matrix is 10 or greater.

The processor 113 may then select a helix matrix and a balance matrix corresponding to the number of selected dimensions. When the processor 113 selects a helix matrix and a balance matrix, the server 120 may store the selected helix matrix and balance matrix information.

The processor 113 may calculate the data encryption matrix through the multiplication of the legacy matrix and the balance matrix.

For example, N -1 of balance matrix (M _1, M _2, ..., M _{N -1)} and one oil-based matrix (M _N) in this case is selected, data encryption, matrix (M) is N -1 of balance Can be computed through the multiplication of a matrix and a relational matrix. The data encryption matrix is first ( M _N x M _{N- 1} ), and multiplying the calculated value by M _N-2 again. That is, the data encryption matrix M {(( M _N x M _N-1 ) x ... x M ₂ ) x M ₁ }.

For example, based on Equation 1, it is possible to calculate the encrypted data matrix M from a single balance matrix (M ₁₎ and one oil-based matrix (M _2). In Equation (1), m ₁ is the number of dimensions of the balance matrix ( M ₁ ), and m ₂ is the number of dimensions of the relational matrix ( M ₂ ). J is a square matrix in which all the elements of m ₁ X m ₁ are 1. In addition, the data encryption matrix M is a square matrix in which the size of a row and a column is ( m ₁ X m ₂ ).

이다. 이때,

는

이므로, 이므로, 1행 1열부터 3 행 3열까지의 원소는

이 될 수 있다. For example, Equation 1 in the formula for calculating the elements of from 1 to row 1, column _1, line m ₁ m column. That is, according to the example described above, the expression for calculating the elements from row 1 to column 3, row 3

to be. At this time,

The

, So the elements from row 1 to row 3 to column 3 are

.

That is, in the data encryption matrix M , the value of 1 row and 1 column is 0, the value of 1 row and 3 column is 1, and the value of 3 row and 3 column can be 2.

이므로, 1행 10열부터 3행 12열까지의 원소는

가 될 수 있다. The equation for calculating the elements from row 1 to column 3 to column 12

, The elements from row 1 to row 3 to row 12 are

.

The data encryption matrix may be computed after receiving the residual matrix and the uniformity matrix from the terminal 120 at the terminal 110. In addition, the data encryption matrix may be calculated by the server 120 and then transmitted to the terminal 110.

For example, if a data encryption matrix is computed at the terminal 110, the processor 113 may receive the selected population matrix and at least one balance matrix from the server 120 to yield a data encryption matrix.

In addition, when a data encryption matrix is calculated at the server 120, the processor 113 may transmit information of the selected population matrix and at least one balance matrix to the server 120. [ When the server 120 calculates the data encryption matrix, the processor 113 can receive the calculated data encryption matrix through the communication module 111. [ Alternatively, the processor 113 may transmit a key to the server 120 via the communication module 111 and receive a row corresponding to the key from the server 120. [

The processor 113 may then reorder the raw data based on the computed data encryption matrix. At this time, the processor 113 may select a row to be used for reordering based on the key. When the user selects a key for data encryption, the processor 113 can store the key in the memory 112. [

At this time, the key may be selected by the user through the terminal 110 to store the raw data. The key may be a value greater than or equal to 1 and may be a value less than or equal to the product of the inference matrix and the dimension of each of the at least one balance matrix.

3 is an exemplary diagram of a data encryption matrix according to one embodiment of the present invention.

For example, referring to FIG. 3, the processor 113 may calculate a data encryption matrix through multiplication of one leg matrix ( M ₂ ) and one balance matrix ( M ₁ ). If the user selects "6 " which is the index of the 7th row with the key, the processor 113 can select the 7th row of the data encryption matrix.

The processor 113 may reorder the data to be stored using the seventh row selected in the data encryption matrix.

4 is an illustration of data according to an embodiment of the present invention.

Referring to FIG. 4, the processor 113 may rearrange the raw data as shown in FIG. 4A and store the same in the database 122 of the server 120 as shown in FIG. 4B. At this time, the raw data can be sorted in descending order according to the attribute "No"

The processor 113 may first use the key to select data to be stored in the server 120 among the raw data. The processor 113 may then transmit the selected data to the server 120 and store the selected data in the database 122 of the server 120. [

For example, the processor 113 may select data to be stored in the server 120 based on the y value satisfying " M [key] [ y ] = h ". Here, M represents a data encryption matrix, and y may be a current index of data to be stored in the server 120. In addition, h may be a procedure for selecting data to be stored in the server 120.

The processor 113 may select data to be stored in the server 120 as the first of the raw data. At this time, the processor 113 may set the variable h to 0 in order to select the first data. Then, the processor 113 can find " y " value "6" satisfying " M [6] [ y ] = 0" in the data encryption matrix. Therefore, the processor 113 can select the seventh data "Green ", 901212, " M ", and "AAA" The processor 113 may transmit the selected data to the server 120 via the communication module 111. [

The server 120 may store the data received from the terminal 110 in the database 122 in order. Therefore, the seventh data transmitted from the terminal 110 is stored in the database 122 as the first data.

At this time, the data transmitted from the processor 113 to the server 120 may be encrypted. That is, the processor 113 may perform encryption before transmitting data to the server 120, such as " Green ", 901212, 'M', and 'AAA' Processor 113 may transmit the encrypted data to server 120 in response to < < Green >, 901212, 'M', 'AAA' The server 120 may then store the encrypted data in the database 122 of the server 120. [

Further, the processor 113 can select the second data among the raw data. For this purpose, the processor 113 may set h to 1 by incrementing h by one. The processor 113 can find the y value "8" that satisfies " M [6] [ y ] = 1" in the data encryption matrix. Therefore, the processor 113 selects the ninth data "Isabella ', 910815,' F ', and' CCC '>" .

The server 120 receiving the data from the terminal 110 may store the received data in the database 122 of the server 120. [ At this time, the server 120 may store the data in the order received from the terminal 110. Therefore, in the database 122 of the server 120, data is written in the order of "<Green ', 901212,' M ',' AAA '>" and "<Isabella', 910815, And stored.

In this way, the processor 113 can select data to be stored in the server 120 among the raw data while increasing the value of h by 1. And the processor 113 may transmit the selected data to the server 120 through the communication module 111. [

Referring again to FIG. 4, the reordering data may be stored in the database 122 of the server 120, as shown in FIG. 4 (b). That is, the data stored in the database 122 of the server 120 may be stored according to the order transmitted by the terminal 110. Therefore, as shown in FIGS. 4A and 4B, the order of the raw data of the terminal 110 and the data stored in the database 122 of the server 120 may be different.

Meanwhile, the processor 113 may receive data corresponding to a user's search request from the server 120 according to a search request of the user. At this time, the user's search request may be a query to the database 122.

As described above, when the processor 113 stores the raw data in the server 120, the processor 113 does not store the reordering information on the stored raw data, so that it is not possible to know the location where the data corresponding to the user's search request is stored. Also, since the data stored in the server 120 is encrypted data, the server 120 can not confirm exactly what data corresponds to the user's search request.

Therefore, when the processor 113 stores the raw data, the search range can be set based on the selected permutation information and the key. The processor 113 may repeatedly check the data stored in the database 122 of the server 120 in a direction of reducing the set range to retrieve data corresponding to the user's search request.

At this time, the raw data is data arranged for a specific attribute. Therefore, based on this feature, the processor 113 may perform a binary search.

A binary search technique is a search technique that locates a specific value in an ordered set of data. Specifically, the binary search technique sets a range for all data and selects a median within a set range. The binary search technique performs a search by comparing whether data corresponding to the selected median is larger or smaller than search target data.

If the data corresponding to the median value is larger than the data to be searched, the binary search technique sets the median value to the new maximum value of the range, selects the median value again, and repeats the comparison. If the data corresponding to the median value is smaller than the data to be searched, the binary search technique sets the median value to the new minimum value of the range, selects the median value again, and repeats the comparison. Through this method, the binary search technique can search the desired information by reducing the search range.

The processor 113 according to an embodiment of the present invention may search for search target data corresponding to a user request according to a binary search method. To this end, the processor 113 first calculates the index of the data stored in the server 120 to be searched based on the permutation information, the range, and the key.

At this time, as described above, the permutation information may be stored in the server 120 when the terminal 110 selects the raw data. The range may be calculated based on the permutation information selected by the terminal 110 when storing the raw data in the server 120. The key may be stored in the memory 112 of the terminal 110 after use in storing the raw data in the database 122 of the server 120.

The processor 113 transmits the index of the calculated data to the server 120 via the communication module 111. [ The processor 113 receives data corresponding to the index of the data from the server 120. The processor 113 may compare the data received from the server 120 with the data to be searched. When the received data and the data to be searched are different, the processor 113 can calculate a new range based on the index of the calculated data.

If the received data is larger than the search target data, the processor 113 can set a new maximum value based on the index of the data. The processor 113 may then calculate the new range using the minimum value of the previous range and the new maximum value.

Further, when the received data is smaller than the search target data, the processor 113 can set a new minimum value based on the index of the data. The processor 113 may then calculate a new range based on the new minimum value and the maximum value of the previous range.

The processor 113 may re-index the data based on the calculated new range and key. The processor 113 may transmit the index of the re-calculated data to the server 120 and receive the data corresponding to the index of the data again.

The processor 113 may repeat the process of resetting and searching the range until the received data is the same as the data to be searched. If the received data and the data to be searched are the same, the processor 113 can provide the received data to the user.

5 is an exemplary diagram of data retrieval according to an embodiment of the present invention.

For example, referring to FIG. 5, the server 120 may store the permutation information selected by the processor 113 of the terminal 110 when storing raw data. In addition, the server 120 may store the data received from the processor 113 of the terminal 110 in the database 122.

The processor 113 may receive a search request for data whose "No attribute" value is "920311" from the user. That is, the search target data may be data whose value of "No attribute" is "920311".

First, the processor 113 can set a search range for data to be searched. As previously described, the size of the data may be less than or equal to the product of the dimensions of the inference matrix and the balance matrix. Therefore, the processor 113 can predict the size of the data based on the pre-stored permutation information.

Since the relational matrix stored in the permutation information is a " 4 x 4 matrix "(4-dimensional) and the balance matrix is 3 x 3 (3-dimensional), the processor 113 determines that the size of the data is smaller than 12, . Therefore, the processor 113 can set the search range for the data stored in the database 122 to the index "0" to the index "11" or less.

The processor 113 may select a median of the set range and select a column of the data encryption matrix to be used for the search. At this time, the processor 113 can select the median value based on [Equation 2]. In Equation (2), low is the minimum value of the range, and high is the maximum value of the range. Also, y is the column to be used in the search, and the floor () function is a function that discards decimal places.

Since low = 0 and high = 11 through the currently set range in Equation (2), y becomes 5. That is, the processor 113 may calculate "5" as the column index of the data encryption matrix to be used for the search. Since the key used for data storage is "6 &quot;, the processor 113 can use the value of the calculated data encryption matrix" M (6, 5) "through the permutation information as an index of data to be transmitted to the server 120 . That is, since the value of the 7th row and 6th column of the data encryption matrix is 10, the processor 113 can set "10" as an index of the data. And the processor 113 may deliver "10"

When the server 120 receives "10" from the terminal 110, the server 120 can retrieve the 11th data of which the index of the data is "10" among the data stored in the database 122. The server 120 may then transmit the 11th data "<'Frank', 901018, 'M', 'GGG'>" to the terminal 110.

The processor 113 of the terminal 110 can receive "<'Frank', 901018, 'M', 'GGG'>'from the server 120 via the communication module 111. The search target data and the data received from the server 120 can be compared. The "No attribute" value "901018" of the data received from the "No attribute" value "920311" of the search object data is small. Therefore, the processor 113 can reset the value "6 &quot;, which is one greater than the column index" 5 "of the data encryption matrix used for the search, to the new low . So in the new range low is 6 and high can be 11.

Based on Equation (1), the processor 113 can select a median value of "8" for the new range. That is, the processor 113 can select "1", which is the value of the data encryption matrix " M (6, 8)", as the index of the data. The processor 113 transmits the index "1" of the data to be used for the selected search to the server 120 and the second data "<Isabella ', 910815, F ', and' CCC '>".

The processor 113 can compare the value "910815" of the "No attribute" included in the received data with the value "920311" of the "No attribute" of the data to be searched. Since the value received from the server 120 is small, the processor 113 can reset 9, which is a value one higher than 8, which is the column used for the search, to a new low . So the new low is 9, and the high can be 11.

According to the above-described method, the processor 113 can select 8, which is the value of the 6th row and 10th column of the data encryption matrix M, as an index to be used as an index to be used for retrieval, according to the new range. Processor 113 may forward 8 to server 120 and receive data corresponding to index 8 from server 120, e.g., <Kelly ', 930208,' F ',' AAA '>.

The processor 113 can compare the No attribute value "930208" included in the received data with the No attribute value "920311" Since the value received from the server 120 is large, the processor 113 can reset "9", which is one less than "10", which is the column index of the data encryption matrix used for the search, to the new high of the range. Thus, the new low and high of the range can all be nine.

Again, the processor 113 may select "6", the value of the data encryption matrix M (6, 9), as the index of the data to be used in the search, according to the new range. The processor 113 transfers the data index "6" to the server 120 and receives data "<'John', 920311, 'M', 'AAA'"

The processor 113 can compare the "No attribute" value "920311" included in the received data with the "No attribute" value "920311" of the search object data. Since the value of the "No attribute" received from the server 120 is the same as the value of the "No attribute" of the data to be searched, the processor 113 completes the search and outputs the search result "<'John', 920311, 'AAA'> "to the user.

Meanwhile, the terminal 110 according to an embodiment of the present invention may generate a data encryption matrix each time a search is performed, or may receive and use a data encryption matrix from a server. Specifically, when the terminal 110 performs the search, it may transmit the row and column indexes corresponding to the data encryption matrix to the server 120. The terminal 110 can receive the value of the data encryption matrix corresponding to the row and column index from the server 120 and set the index of the data to be used for the search.

Therefore, the server 120 can generate a data encryption matrix based on the permutation information selected by the terminal 110 in advance when the terminal 110 performs a search or at the request of the terminal 110. [ When the server 120 receives the row and the column from the terminal 110, the server 120 may calculate an index from the generated data encryption matrix and transmit the index to the terminal 110.

Also, the terminal 110 according to another embodiment of the present invention can calculate the index of the data to be searched through [Equation 3] to [Equation 5].

Specifically, the terminal 110 can calculate the row ( q _x ) of the residual matrix and the row ( r _x ) of the balance matrix according to the row ( R ) of the data encryption matrix through the formula (3). For example, because the index of the line is "6", the dimensional size of the balance of the matrix, "3", [Equation 3] is "6 = _x q X 3+ r _x "may be. At this point," _x r ", so less than the number of dimensions of the balanced matrix," _x q "is""andthe," r 2 _x "is" can be zero. "

( Q _y ) and a column ( r _y ) of the balance matrix according to the column ( C ) of the data encryption matrix can be calculated through the equation (4). For example, if the index of the column is "5", since the dimensional size of the balance of the matrix, "3", [Equation 4] "5 = X q _y 3+ r _y "may be. At this time," r _y ", so less than the number of dimensions of the balanced matrix," q _y "is""tobe," _y 1 r "is" may be a 2 ".

In other words, the processor 113 of the terminal 110 obtains the row ( q _x ) in the relational matrix according to the row ( R ) and column (C) of the data encryption matrix through the equations (3) And columns ( q _y ) and rows (r _x ) and columns ( r _y ) in the balance matrix. Then, based on the formula (5) and the value of each matrix, the processor 113 can calculate the index ( i ) of the data.

Meanwhile, the processor 113 of the terminal 110 according to an embodiment of the present invention may select the permutation information in consideration of a sufficient data size in storing the initial primitive data, in case the data is added to the primitive data . When the data is added, the processor 113 can perform reordering on the additional data based on the previously selected permutation information and transmit it to the server 120. [

The server 120 may store additional data received in the data space in which the existing data of the database 122 is stored, when additional data is received.

In addition, the processor 113 according to another embodiment of the present invention transmits data to the server 120 when data is added to the raw data, and adds the data to the existing data stored in the database 122 in a linked-list form Data can be stored.

Specifically, the processor 113 of the terminal 110 may select the permutation information when the additional data is generated, and reorder the additional data based on the selected permutation information. And may send the reordered additional data to the server 120.

The server 120 may store the received additional data in the database 122. At this time, the server 120 may connect the received additional data to the existing stored data in the form of a linked list. Therefore, the additional data stored in the server 120 can be linked to existing data.

In addition, the processor 113 according to another embodiment of the present invention can rearrange the existing data and the additional data by merging the data when the data is added to the original data. To this end, the processor 113 may again select permutation information for the merged data. Then, the processor 113 may transmit the merged merge data to the server 120 according to the selected permutation information to be stored.

Next, a search method of the data search terminal 110 according to an embodiment of the present invention will be described with reference to FIG.

6 is a flowchart of a search method of the data search terminal 110 according to an embodiment of the present invention.

The data search terminal 110 calculates an index corresponding to the search target data among the data stored in the server 120 based on the range and the key (S600). At this time, the range is calculated based on the permutation information received from the server 120. Also, the key is set corresponding to the data stored in the server 120.

In addition, the data search terminal 110 transmits the calculated index to the server 120 (S610).

The server 120 can retrieve data corresponding to the index calculated from the data search terminal 110 through the database 122 of the server 120. [ The server 120 may transmit the retrieved data to the data retrieval terminal 110.

The data search terminal 110 receives data corresponding to the index calculated from the server 120 (S620).

The data search terminal 110 may compare the received data with the search target data (S630).

If the data received from the server 120 is not matched with the data to be searched, the data search terminal 110 can extract the searched range (S640).

When the data received from the server 120 matches the search target data, the index is calculated (S600), and the calculated index is transmitted to the server 120 (S610) based on the re-calculated range and key, , The data corresponding to the transmitted index is received (S620), and the received data is compared with the search target data (S630).

Meanwhile, the data search terminal 110 may store the raw data in the database 122 of the server 120 before calculating the index.

Specifically, the data search terminal 110 can receive the permutation information from the server 120. [

The data search terminal 110 can select a key based on the permutation information. Then, the data search terminal 110 can rearrange the raw data based on the selected key and permutation information.

The data retrieval terminal 110 may transmit the reordered raw data to the server 120 for storage in the database 122 of the server 120. [

The data search terminal 110 and the search method thereof according to an embodiment of the present invention can rearrange the data in the terminal 110 and transmit the data to the server 120 and store the data in the database 122 of the server 120. [ Therefore, the data search terminal 110 and its searching method can guarantee the stability of the data stored in the server 120. [ In addition, the data search terminal 110 and the search method thereof may perform an efficient search for the encrypted data stored in the server 120 through the binary search. Therefore, the data retrieval terminal 110 and its retrieval method can prevent data leakage and provide quick retrieval of the encrypted data.

One embodiment of the present invention may also be embodied in the form of a recording medium including instructions executable by a computer, such as program modules, being executed by a computer. Computer readable media can be any available media that can be accessed by a computer, and includes both volatile and nonvolatile media, removable and non-removable media. The computer-readable recording medium may also include computer storage media. Computer storage media includes both volatile and nonvolatile, removable and non-removable media implemented in any method or technology for storage of information such as computer readable instructions, data structures, program modules or other data.

While the methods and systems of the present invention have been described in connection with specific embodiments, some or all of those elements or operations may be implemented using a computer system having a general purpose hardware architecture.

It will be understood by those skilled in the art that the foregoing description of the present invention is for illustrative purposes only and that those of ordinary skill in the art can readily understand that various changes and modifications may be made without departing from the spirit or essential characteristics of the present invention. will be. It is therefore to be understood that the above-described embodiments are illustrative in all aspects and not restrictive. For example, each component described as a single entity may be distributed and implemented, and components described as being distributed may also be implemented in a combined form.

The scope of the present invention is defined by the appended claims rather than the detailed description and all changes or modifications derived from the meaning and scope of the claims and their equivalents are to be construed as being included within the scope of the present invention do.

100: Data retrieval system
110: terminal
111: Communication module
112: memory
113: Processor
120: Server
121: Permutation information
122: Database

Claims (14)

1. A terminal for searching data stored in a server,
Communication module,
The data retrieval program stores the memory and
And a processor for executing the program,
Wherein the processor calculates the index corresponding to the data to be searched among the data stored in the server based on the range and the key according to the execution of the program and transmits the calculated index to the server, Receiving the data corresponding to the index,
The range is calculated based on the permutation information received from the server,
Wherein the key is set corresponding to data stored in the server,
Wherein the processor receives the permutation information from the server, selects the key based on the permutation information, rearranges the raw data based on the selected key and the permutation information, To the server so as to be stored in a database of the server,
Wherein the permutation information comprises a bounded matrix and at least one balanced matrix. The method according to claim 1,
The processor compares the data received from the server and the data to be searched, re-calculates the range if the data received from the server and the data to be searched do not match,
Calculating an index based on the re-calculated range and the key until the data received from the server and the data to be searched match; transmitting the re-calculated index to the server; And re-receiving the data corresponding to the re-calculated index. The method according to claim 1,
Wherein the processor searches the data to be searched based on the binary search method. delete The method according to claim 1,
Wherein the processor is operative to calculate a product of a dimension of the relic matrix and a dimension of the at least one balance matrix and to select the relic matrix and the at least one balance matrix such that the calculated product is greater than the number of data,
And selects a value less than or equal to the calculated product with the key. 6. The method of claim 5,
Wherein the processor sequentially selects data to be stored in the server based on the selected key and the received permutation information and transmits the selected data to the server. The method according to claim 1,
Wherein the relational matrix is a matrix in which elements of the same value are included in the same column below a predetermined value,
Wherein the balance matrix is a matrix in which the same element is not included in the same column. The method according to claim 1,
Wherein the raw data is arranged for specific attributes included in the raw data. The method according to claim 1,
Wherein the processor generates a relational matrix and reorders the raw data based on the generated relational matrix and one or more balance matrices received from the server and stores the relational matrix in the memory. The method according to claim 1,
The processor reorders the additional data based on the selected key and the permutation information when data is added and transmits the reordered additional data to the server so that the reordered additional data is stored in the server,
Wherein the permutation information is selected based on the size of the raw data and the additional data. A method for searching a data stored in a server in a terminal,
Selecting the key based on permutation information received from a server;
Rearranging the raw data based on the key and the permutation information;
Transmitting the reordered raw data to the server to be stored in a database of the server;
Calculating an index corresponding to the data to be searched among the data stored in the server based on the range and the key;
Transmitting the calculated index to the server; And
And receiving data corresponding to the calculated index from the server,
The range is calculated based on the permutation information,
Wherein the key is set corresponding to data stored in the server,
Wherein the permutation information comprises a bounded matrix and at least one balanced matrix. 12. The method of claim 11,
Comparing the received data with the search target data after receiving the data; And
If the data received from the server does not match the search object data,
Calculating the index based on the re-calculated range and the key until the data received from the server matches the search object data, transmitting the calculated index to the server, Wherein the step of receiving and the step of comparing are repeated. delete A computer-readable recording medium recording a program for performing the method according to any one of claims 11 to 12 on a computer.

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