JP2008005396A - Data transmission method and system, program, and recording medium - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a data transmission method with which terminal individual identification can not be performed, but when a terminal is copied, the copy can be detected and specified. <P>SOLUTION: A method of transmitting data from terminals 2-1 to 2-m to a receiving server 3 in a configuration where a group of the plurality of terminals 2-1 to 2-m, an administrative server 1 and the receiving server 3 are connected via a network 100, includes the steps of: transmitting from the administrative server 1 to the corresponding terminals 2-1 to 2-m data containing terminal identification information encrypting different numbers allocated to the terminals 2-1 to 2-m using an encryption key shared with the receiving server 3; transmitting from the terminals 2-1 to 2-m to the receiving server 3 terminal identification information received from the administrative server 1, stored, applied to transmission data, and encrypted using a public encryption key common for the terminals; and confirming, at the receiving server 3, whether the number is overlapped which is obtained by further decrypting the terminal identification information which is obtained by decrypting received data using a corresponding private key, using the encryption key shared with the administrative server 1. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a data transmission method and system.

In order to prevent spoofing due to terminal duplication, terminal authentication is required between the terminal and the receiving server. For example, various methods such as a password method and a shared secret key method are used as authentication methods (hereinafter referred to as individual authentication methods) that can identify individual terminals. When these individual authentication methods are used, when a certain terminal is duplicated and used at the same time as the original, message transmission from the same individual to the receiving server is performed simultaneously from different points, so that the receiving server detects the duplication of the terminal. Can do. However, when the individual authentication method is used, there is a problem in that the location of each terminal is known to the receiving server and the location privacy of the user who owns the terminal is infringed. For example, in the case of a system where volunteers own terminals, the terminals measure data appropriately, send measurement data from the terminals to the receiving server, and collect the measured data at the receiving server, in order to protect the privacy of each volunteer For this, an authentication method in which the manager of the receiving server cannot know the location of each volunteer is desirable. As a countermeasure against this problem, there can be considered a scheme in which authentication is performed in units of terminals as shown in Non-Patent Document 1 and Non-Patent Document 2. For example, by distributing the same public key to each terminal and authenticating the receiving server with the paired secret key, the individual terminal cannot be identified, but it is possible to authenticate to which group it belongs.
Kato, Anonymous Authentication Technology and its Applications, “Toshiba Review”, Toshiba Corporation, 2005, Vol. 60, no. 6, p. 23-27 G. Affiliates, A Practical and Probable Secure Coalition-Resistant Group Signature Scheme, 2000, “Avaces in Cryptology-CRYPTO2000. 255-270

  However, in the above technique, unless a message is transmitted from all terminals, it is impossible to detect a copy, and even if a copy is detected, it is not possible to specify which individual has been copied. There's a problem.

  The present invention has been made in consideration of such circumstances, and its purpose is to solve the above-mentioned problems and to authenticate terminals in units of groups, making it impossible to identify individual terminals. In such a case, a data transmission method based on authentication that enables detection and identification of a replica is realized.

  In order to achieve the above object, a data transmission method according to the present invention connects a plurality of terminals, a management server, and a reception server that constitute a group, and receives data (for example, environmental data in the embodiment) from the plurality of terminals to the reception server. A transmission method in which a management server assigns a different number (for example, a temporary ID in the embodiment) to each of a plurality of terminals, and the number is encrypted with a shared encryption key with the receiving server (for example, a server shared secret key in the embodiment). Transmitting the first data (for example, the second terminal identification information and the group name in the embodiment) including the encrypted terminal identification information (for example, the second terminal identification information in the embodiment) to the terminal corresponding to the number; The terminal accumulates the first data received from the management server, and the terminal identification information (for example, the second terminal in the embodiment) in the transmission data A process of transmitting the second data encrypted with a common public encryption key (for example, the group encryption key in the embodiment) between the terminals constituting the group by giving different information) to the receiving server, and the receiving server received Decrypt the second data with a secret key corresponding to the public encryption key (for example, the group secret key in the embodiment), and further decrypt the terminal identification information obtained by the decryption with the shared encryption key with the management server. And a process of confirming whether or not the obtained number is duplicated.

  In the data transmission method according to the present invention, when the receiving server detects that the number obtained by decoding the terminal identification information received from the terminal is duplicated, the receiving server notifies the management server of the duplicate number; And identifying a duplicated terminal from the received number.

  In the data transmission method according to the present invention, in a configuration in which a plurality of terminals constituting a group, a management server, and a reception server are connected via a network, each of the terminals periodically sends a message including data to the reception server. A data transmission method in a transmission system, in which a management server allocates a temporary ID that is a different number to each terminal in advance for each data transmission cycle, holds it in a terminal management information storage unit, and guarantees authentication A terminal identification information list in which the data transmission cycle information corresponding to the temporary ID (for example, the transmission cycle number in the embodiment) is encrypted with the shared secret key with the receiving server, and the encrypted information is arranged in the data transmission order for each terminal. The process of generating and distributing the first data including the terminal identification information list to the corresponding terminals, and each terminal receiving the received first data The terminal identification information is stored in the identification information storage unit, and when transmitting data, the terminal identification information corresponding to the data transmission cycle information is read from the terminal identification information storage unit, and the transmission data and the terminal identification information are shared by the terminals constituting the group A process of transmitting to the receiving server the second data encrypted with the encryption key and assigned a group ID (for example, a group name in the embodiment) for identifying the group to the encrypted data, and the receiving server receives the received second data The second data is decrypted with the secret key corresponding to the public encryption key, which is read from the encryption key storage unit that stores the encryption key corresponding to the group ID included in the ID, and the decrypted terminal identification information is further shared with the receiving server The data transmission cycle information obtained by decrypting with the secret key is information indicating the time when the second data is received (for example, the transmission cycle number in the embodiment). If it corresponds, the terminal of the transmission source of the second information is determined to belong to the group, and the temporary ID included in the second data and each terminal are received within the period in which the second data is received. And a step of determining whether or not there is an overlap with the received temporary ID.

  In the data transmission method according to the present invention, each terminal periodically transmits a message including data to a reception server in a configuration in which a plurality of terminals constituting a group, a management server, and a reception server are connected via a network. In the data transmission method in the system, when it is detected that there is duplication in the temporary ID included in the second data received by the receiving server within the period of receiving data, the receiving server The process of transmitting the group ID and the data transmission cycle information indicating the overlapping cycle to the management server, and the management server displays the terminal corresponding to the received temporary ID and the data transmission cycle time in the terminal management table (for example, in the embodiment) And a process of specifying by searching in the terminal management information storage unit 15).

  A data transmission system according to the present invention is a data transmission system in which a plurality of terminals constituting a group, a management server, and a reception server are connected, and data is transmitted from the plurality of terminals to the reception server. A temporary ID generation unit that assigns a temporary ID that is a different number to each terminal, a terminal management information storage unit that stores the temporary ID and the data transmission cycle information in association with each other, and a temporary storage for a cycle that guarantees authentication. The ID and the corresponding data transmission cycle information are encrypted with the shared secret key with the receiving server, a terminal identification information list in which the encrypted information is arranged in the order of data transmission for each terminal is generated, and the terminal identification information list is included. A management server having an encryption unit for distributing the first data to the corresponding terminal, a terminal identification information storage unit for storing the received first data, and a data transmission time The terminal identification information corresponding to the data transmission cycle information is read from the terminal identification information storage unit, the transmission data and the terminal identification information are encrypted with a common public encryption key between the terminals constituting the group, and the encrypted data And an encryption key storage that stores an encryption key in association with the group ID included in the received second data, and a terminal having an encryption unit that transmits the second data to which the group ID for identifying the group is assigned to the receiving server And a decryption unit that decrypts the second data with a secret key corresponding to the public encryption key read from the encryption key storage unit, and further decrypts the decrypted terminal identification information with the shared secret key with the receiving server, and If the data transmission cycle information corresponds to the information indicating the time when the second data is received, the group authentication unit that determines that the terminal that has transmitted the second information belongs to the group And a receiving server having a duplication judgment unit for judging whether or not there is duplication between the temporary ID included in the second data and the temporary ID received from each terminal within the period in which the second data is received. It is characterized by that.

  In the data transmission system according to the present invention, each terminal periodically transmits a message including data to a receiving server in a configuration in which a plurality of terminals constituting a group, a management server, and a receiving server are connected via a network. In the data transmission method in the system, when it is detected that there is duplication in the temporary ID included in the second data received by the receiving server within the period of receiving data, the receiving server The terminal management table is searched for a receiving server having a duplication determination unit that transmits the group ID and data transmission cycle information indicating the overlapping cycle to the management server, and a terminal corresponding to the received temporary ID and data transmission cycle time. And a management server having means for specifying.

  As described above, according to the present invention, terminals are authenticated in groups and identification of individual terminals is impossible. However, when a terminal is duplicated, it is possible to detect and specify a duplicate. There is an effect.

Next, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a block diagram showing the overall configuration of a data transmission system according to the present invention. In this embodiment, a plurality of terminals constituting a group periodically receive and collect messages including environmental data such as air pollution data and temperature and humidity collected via a network 100 that is a communication network. The case of transmitting to 3 will be described as an example.
At this time, the receiving server 3 holds only environmental data corresponding to the temporary ID, and the management server 1 holds only the temporary ID generated corresponding to the terminal and information for identifying the corresponding terminal. 3 is a configuration in which the correspondence between the temporary ID and the terminal cannot be identified, and the management server 1 does not hold the environmental data, so that the position information and time information when the terminal transmits the environmental data cannot be specified.

In this figure, the data transmission system is connected via a network 100 to a management server 1 that manages terminal identification information, terminals 2-1 to 2-m that transmit data, and a reception server 3 that receives and stores the data. Has been.
The network 100 includes a public network such as a fixed telephone network, a mobile phone network, and the Internet, a private network such as a LAN (Local Area Network) and a dedicated line, a mobile network, and a short-range communication network.

In the management server 1, the communication unit 10 realizes communication with the terminals 2-1 to 2-m or the reception server 3 via the network 100.
As shown in FIG. 2, the terminal information storage unit 16 has information for identifying the terminals 2-1 to 2-m, for example, destination information when transmitting data from the management server 1 to the terminals 2-1 to 2-m ( Address information) is stored in advance for each group.

  The temporary ID generation unit 11 generates a temporary ID to be assigned for each data transmission cycle of each of the terminals 2-1 to 2-m. Here, the transmission cycle number is a number indicating the number of data transmission cycles of the terminals 2-1 to 2-m. At this time, the temporary ID generation unit 11 searches the encryption key storage unit 17 for a corresponding group name. An ID generation secret key is read as a key, and the temporary ID is generated by encrypting the first terminal identification information and the transmission cycle number with the read ID generation secret key. Further, the temporary ID generation unit 11 writes the generated temporary ID in a table corresponding to the terminal destination in association with the data transmission cycle. A table corresponding to the terminal destination is stored in the terminal management information storage unit 15.

As shown in FIG. 3, the encryption key accumulating unit 17 stores a server shared secret key with the receiving server 3 and an ID generation secret key in advance in association with the group name.
As shown in FIG. 4, the terminal management information storage unit 15 stores a group name in advance for each terminal destination. In addition, the temporary ID for each transmission cycle number of the terminal is associated with the corresponding transmission cycle number and written to the corresponding terminal destination table by the temporary ID generation unit 11.

  The encryption unit 12 encrypts the first transmission cycle number and the temporary ID with the server shared secret key with the receiving server 3 using the transmission cycle number as the first transmission cycle number, and the ciphertexts in the order of the transmission cycle numbers. It arranges and transmits to the corresponding terminals 2-1 to 2-m via the communication unit 10 as the second terminal identification information. At this time, the encryption unit 12 reads the server shared secret key with the receiving server 3 from the encryption key storage unit 17 using the corresponding group name as a search key. The first transmission cycle number is information used for group authentication in the receiving server 3.

Next, the configuration of the terminals 2-1 to 2-m that transmit data will be described.
The communication unit 20 realizes communication with the management server 1 or the reception server 3 via the network 100. Further, the communication unit 20 writes the second terminal identification information transmitted from the management server 1 in the terminal identification information storage unit 27.

The cycle unit storage unit 25 stores in advance a cycle unit indicating a period of one cycle in which data is transmitted and a data transmission start time.
The cycle number storage unit 26 stores a transmission cycle number indicating the number of times environment data has been transmitted.

The transmission time management unit 21 calculates a data transmission time, and outputs a data collection command to the data collection unit when the transmission time is reached.
Based on the input data collection command, the data collection unit 22 measures and collects environmental data that is a combination of one or more of air pollution status, temperature, humidity, and rainfall with a corresponding sensor. The environmental data thus obtained is output to the encryption unit 23.

When receiving the environment data, the encryption unit 23 reads the transmission cycle number from the cycle number storage unit 26. The encryption unit 23 reads the second terminal identification information corresponding to the read transmission cycle number and the group name from the terminal identification information storage unit 27. The encryption unit 23 reads the group encryption key from the encryption key storage unit 28 using the read group name as a search key.
The encryption unit 23 encrypts the second transmission cycle number, the second terminal identification information, and the environment data with the read group encryption key using the transmission cycle number as the second transmission cycle number, and stores the security information. In addition, the collected data is transmitted to the receiving server 3 via the communication unit 20. This security information includes a group name.
At this time, the group encryption key is a public encryption key that is common among terminals belonging to the same group, and decryption can be performed only with the group secret key that is a secret key possessed only by the receiving server 3. The second transmission cycle number is information used for group authentication in the receiving server 3.

  As shown in FIG. 5, the terminal identification information storage unit 27 stores the second terminal identification information in the order in which data is transmitted.

In the receiving server 3, the communication unit 30 receives the collected data and outputs it to the decoding unit 31. In addition, when a duplicate terminal due to impersonation is detected, the communication unit 30 transmits information identifying the duplicate terminal to the management server 1.
The decryption unit 31 extracts the group name from the security information of the collected data received by the communication unit 30, and reads the group secret key and the server shared secret key from the encryption key storage unit 35 using the extracted group name as a search key. . The decryption unit 31 decrypts the second transmission cycle number, the second terminal identification information, and the environment data using the read group secret key. The decryption unit 31 further decrypts the decrypted second terminal identification information with the read server shared secret key, and obtains a temporary ID and a first transmission cycle number.
The decryption unit 31 outputs the obtained reception data to the group authentication unit 32.

As shown in FIG. 6, the encryption key storage unit 35 stores a group secret key and a server shared secret key as a table in association with a group.
As shown in FIG. 7, the data storage unit 37 stores environment data in association with the temporary ID in a table for each cycle number.

  The group authenticating unit 32 authenticates whether the received data is transmitted from a terminal belonging to the correct group depending on whether the security information and the decrypted information are the same among the input received data. When group authentication is performed, the group authentication unit 32 outputs received data to the duplication determination unit 33. When group authentication is rejected, the group authentication unit 32 discards data as invalid data.

  The duplication determination unit 33 determines whether or not the received data is data obtained by impersonation by a duplication terminal. This determination is performed by referring to the collection ID storage unit 36 that stores the received temporary ID for each period. If the temporary IDs do not overlap, the duplication determination unit 33 writes the environment data in the table of the data storage unit 37 corresponding to the transmission cycle number in association with the temporary ID.

Next, an example of the operation of the system in the configuration shown in FIG. Here, a case where environment data is periodically transmitted from the terminals 2-1 to 2-m belonging to the Δ □ information group to the receiving server 3 will be described as an example.
This operation includes the pre-processing process performed before the first data transmission from the terminals 2-1 to 2-m to the receiving server 3 is started, and the data from the terminals 2-1 to 2-m to the receiving server 3. It consists of two processes, a data transmission process for transmitting.

<Pre-processing process>
In the management server 1, the temporary ID generation unit 11 reads terminal destination information, which is first terminal identification information of all terminals belonging to the Δ □ information group, from the terminal information storage unit 16. The temporary ID generation unit 11 reads the ID generation secret key corresponding to the group name from the encryption key storage unit 17. The temporary ID generation unit 11 generates a temporary ID for one cycle of one terminal by encrypting the transmission cycle number and the read first terminal identification information with the read ID generation secret key. The ID and the transmission cycle number corresponding to the ID are written in the table of the terminal management information storage unit 15 corresponding to the terminal destination information.
The temporary ID generation unit 11 repeats this operation for n times, for example, as the number of cycles for guaranteeing authentication, that is, the number of times that data is scheduled to be transmitted from the terminals 2-1 to 2-m to the receiving server 3. A temporary ID is generated. The temporary ID generation unit 11 outputs first terminal identification information for identifying the terminal to the encryption unit 12 (step S1).

  The encryption unit 12 reads a table corresponding to the input first terminal identification information from the terminal management information storage unit 15. Further, the encryption unit 12 reads the server shared secret key corresponding to the read group name from the encryption key storage unit 17. The encryption unit 12 encrypts the transmission cycle number serving as the first transmission cycle number and the temporary ID for each transmission cycle with the read server shared secret key to generate second terminal identification information (step S2). After the encryption unit 12 repeats the generation of the second terminal identification information for the number of transmission cycles, the encryption unit 12 receives the second terminal identification information and the group name in the order of the transmission cycle number. To the terminals 2-1 to 2-m corresponding to the first terminal identification information (step S3).

In the terminals 2-1 to 2-m, the communication unit 20 receives the second terminal identification information and the group name (step S4). The communication unit 20 writes the received second terminal identification information and group name in a table corresponding to the group name stored in the terminal identification information storage unit 27 (step S5).
It is description of the operation | movement which the management server 1 performs in advance the environmental data transmission from the terminal 2-1 to 2-m to the receiving server 3 about all the terminals which belong to the group from the above steps S1 to S5.

<Data transmission process>
Next, the operation when transmitting environmental data from the terminals 2-1 to 2-m to the receiving server 3 will be described. The transmission time management unit 21 reads the data collection start time information and the cycle unit from the cycle unit storage unit 25, and further reads a transmission cycle number indicating the number of times of transmission so far from the cycle number storage unit 26. The transmission time management unit 21 takes the product of the read transmission cycle number and the cycle unit, adds the product to the data collection start time information, obtains the next data transmission time, and always compares the current time with the data transmission time. When the transmission time management unit 21 detects that the current time coincides with the data transmission time, the transmission time management unit 21 transmits collection command information for collecting environmental data to the data collection unit 22 (step S11).

  Upon receiving the collection command information, the data collection unit 22 collects environmental data including position information and outputs the environmental data to the encryption unit 23 (step S12). This position information identifies the position. For example, the GPS function may be added to the terminals 2-1 to 2-m in advance to obtain coordinate information, or the nearest base station of the network 100 may be accessed. The location of the base station may be used as position information.

When receiving the environmental data, the encryption unit 23 reads the transmission cycle number indicating the number of times of transmission from the cycle number storage unit 26 so far, and identifies the second terminal identification information of the number obtained by adding 1 to the transmission cycle number. Read from the information storage unit 27. The encryption unit 23 reads a group encryption key common to the same group from the encryption key storage unit 28, and receives the received environment data, the read second terminal identification information, and a transmission cycle number that becomes the second transmission cycle number. Are encrypted with the group encryption key (step S13). At this time, the second transmission cycle number is a value obtained by adding 1 to the original transmission cycle number.
The encryption unit 23 transmits the encrypted data and the group name that is the security information to the reception server 3 via the communication unit 20, and writes the second transmission cycle number in the cycle number storage unit 26 (step S14). .

  In the receiving server 3, when the communication unit 30 receives the encrypted data and the group name that is the security information, the communication unit 30 outputs the received information to the decryption unit 31 (step S15).

The decryption unit 31 reads the group secret key and the server shared secret key from the encryption key storage unit 35 using the input group name as a search key. This group secret key is an encryption key paired with the group encryption key, and the ciphertext encrypted with the group encryption key can be decrypted only with the paired group secret key.
The decryption unit 31 decrypts the encrypted data input with the read group secret key (step S16). The decryption unit 31 further decrypts the second terminal identification information included in the decrypted data with the read server shared secret key to obtain the first transmission cycle number and the temporary ID, and obtains the second transmission cycle number and the environment. The data, the first transmission cycle number, and the temporary ID are output to the group authentication unit 32 (step S17).

The group authentication unit 32 performs group authentication based on whether or not the input second transmission cycle number matches the first transmission cycle number (step S18).
This is because when malicious information is transmitted by a malicious user from another group of terminals having the same functions as the terminals 2-1 to 2-m, the second terminal identification information and the second If the correct combination of transmission cycle numbers is not acquired, it is possible to discard the data as illegal data by group authentication.

  When group authentication is performed, the group authentication unit 32 outputs the environmental data, the temporary ID, the transmission cycle number, and the group name to the duplication determination unit 33. The duplication determination unit 33 searches the table corresponding to the transmission cycle number stored in the collection ID storage unit 36 using the input temporary ID as a search key, and the matching temporary ID exists in the table corresponding to the transmission cycle number. Whether or not duplication of the temporary ID of the duplication terminal by spoofing is determined according to whether or not (step S19).

  When the matching temporary ID is not found, the duplication determination unit 33 associates the environment information with the temporary ID and writes the table in the table corresponding to the transmission cycle number stored in the data storage unit 37, and further stores the temporary ID. Is written in the table corresponding to the cycle number of the collection ID storage unit 36 (step S20).

When the group determination in step S18 is rejected, the group authentication unit 32 discards the data by regarding the received data as invalid (step S30).
This is because when one of the terminals 2-1 to 2-m is duplicated by a malicious user, the second terminal identification information including the same temporary ID is transmitted from the duplicating terminal and the duplicating source terminal. There is an effect that the presence / absence of the duplicate terminal can be confirmed depending on whether or not there is the same temporary ID.

  When the matching temporary ID is searched, the duplication determination unit 33 discards the environmental data input as illegal data by the duplication terminal for the purpose of impersonation, and further, from the temporary ID and the environmental data corresponding to the temporary ID. Is deleted from the data storage unit 37. The temporary ID, transmission cycle number, and group name are transmitted to the management server 1 via the communication unit 30 as duplicated terminal information (step S40).

  In the management server 1, the communication unit 10 outputs the received temporary ID and transmission cycle number to the temporary ID generation unit 11 (step S41). When the temporary ID and the transmission cycle number are input, the temporary ID generation unit 11 reads the ID generation secret key corresponding to the group name from the encryption key storage unit 17. The temporary ID input by the read ID generation secret key is decrypted, the first terminal identification information and the transmission cycle number are acquired, and the copied terminal is specified. The temporary ID generating unit 11 reissues the temporary ID of the identified terminal and transmits the second terminal identification information to the corresponding terminal in the same manner as in steps S2 to 5 (step S42). At this time, the temporary ID generation unit 11 reissues the temporary ID by encrypting the prime number with the ID generation secret key in addition to the first terminal identification information and the transmission cycle number.

In the present embodiment, the temporary ID is generated by encrypting the terminal identification information and the cycle number with the ID generation secret key, but there is no duplication between terminals belonging to the same group for each data transmission cycle. Any ID may be used as long as it is an ID.
In addition, after transmitting data for the scheduled number of times of transmission from the terminals 2-1 to 2-m to the receiving server 3, when the terminals 2-1 to 2-m continue to transmit data, the steps S1 to S1 are performed. The same operation as in step S5 may be repeated to generate a new temporary ID, and the new second terminal identification information and group name may be transmitted to each of the terminals 2-1 to 2-m.

  In the present embodiment, the group authentication in step S18 is performed using the first transmission cycle number and the second transmission cycle number, but the group is replaced with the first transmission cycle number and the second transmission cycle number. A name may be used, or a plurality of information such as a combination of a group name and a transmission cycle number may be combined.

Further, after specifying the duplicated terminal, the temporary ID generation unit 11 reads all the temporary IDs of the terminal management information storage unit 15 using the first terminal identification information of the specified terminal as a search key, and via the communication unit 10 The temporary ID is transmitted to the receiving server 3. When receiving the temporary ID from the management server 1, the receiving server 3 may store the received temporary ID as the ID of the replication terminal in the collection ID storage unit 36 and discard the illegal data.
In this embodiment, a prime number is used to reissue a temporary ID. However, any temporary ID that is different from the duplicated terminal may be used, so what values are added such as group name and period unit? Can also reissue temporary IDs.

  In this embodiment, the data to be measured and collected is environmental data such as air pollution status. However, the type of data to be collected is any data to be measured or observed such as communication environment data such as radio wave status. Applicable.

In the present embodiment, one server shared secret key is used for each group. However, for example, a different server shared secret key can be set for each fixed period, such as for each transmission cycle number. In this case, the encryption key storage unit 17 and the encryption key storage unit 35 store the server shared secret key in association with each group name and period.
As a result, even if one of the server shared secret keys is analyzed, after obtaining the period and group name to which the server shared secret key should be applied, a temporary ID that does not overlap with other terminals must be used. In this case, the data is not registered in the data storage unit 37 because it is discarded as invalid data by the group authentication unit 32 or the duplication determination unit 33 in the receiving server 3.

According to the data transmission method of this method, the management server 1 having the first terminal identification information for identifying the terminal does not hold the position information included in the environmental data. On the other hand, the receiving server 3 that acquires the position information does not hold the first terminal identification information that identifies the terminal having the position information.
In addition, when impersonation by a duplicate terminal exists, it is possible to discard the corresponding illegal data. Furthermore, when another terminal misrepresents a group, the corresponding illegal data can be discarded.
Therefore, according to the present invention, it is possible to realize a data transmission system that achieves both location privacy protection for people carrying the terminals 2-1 to 2-m, extraction of illegal data, and identification of duplicate terminals. For example, it is applicable to a system in which volunteers own terminals, terminals measure data appropriately, terminals transmit measurement data and location information to the receiving server, and collect measurement data at the receiving server. Is possible.

It is a block diagram which shows the structural example of the data transmission system in the 1st Embodiment of this invention. 4 is a diagram illustrating an example of first terminal identification information stored in a terminal information storage unit 16. 4 is a diagram illustrating an example of an ID generation secret key and a server shared secret key stored in an encryption key storage unit 17. 4 is a diagram illustrating an example of a group name and a temporary ID stored in a terminal management information storage unit 15. 5 is a diagram illustrating an example of second terminal identification information stored in a terminal identification information storage unit 27. 4 is a diagram illustrating an example of a group secret key and a server shared secret key stored in an encryption key storage unit 35. It is drawing which shows an example of the environmental data memorize | stored in the data storage part 37 corresponding to temporary ID in the table for every period number. It is a flowchart which shows the operation | movement flow of the data transmission system by 1st Embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Management server 2-1 to 2-m Terminal 3 Receiving server 10 Communication part 11 Temporary ID production | generation part 12 Encryption part 15 Terminal management information storage part 16 Terminal information storage part 17 Encryption key storage part 20 Communication part 21 Transmission time management part 22 data collection unit 23 encryption unit 25 cycle unit storage unit 26 cycle number storage unit 27 terminal identification information storage unit 28 encryption key storage unit 30 communication unit 31 decryption unit 32 group authentication unit 33 duplication determination unit 35 encryption key storage unit 36 collection ID storage unit 37 Data storage unit 100 Network

Claims (8)

In a configuration in which a plurality of terminals constituting a group, a management server, and a receiving server are connected via a network, each of the terminals is a method of transmitting a message including data to the receiving server,
The management server assigns a different number to each of the plurality of terminals, encrypts the number with a shared encryption key with the receiving server, and the first data including the encrypted terminal identification information corresponds to the number The process of sending to
The terminal accumulates the first data received from the management server, and receives the second data encrypted with a common public encryption key between the terminals constituting the group by adding the terminal identification information to the transmission data. Sending to the server,
The receiving server decrypts the received second data with a secret key corresponding to the public encryption key, and further decrypts the terminal identification information obtained by decryption with the shared encryption key with the management server, And a step of confirming whether or not the number obtained by decoding is duplicated. The data transmission method of claim 1 comprises:
When the receiving server detects that there is a duplication in the number obtained by decoding the terminal identification information received from the terminal,
A process in which the receiving server notifies the management server of the duplicated number;
The data transmission method according to claim 1, further comprising: identifying the duplicated terminal from the number received by the management server. In a configuration in which a plurality of terminals constituting a group, a management server, and a reception server are connected via a network, each of the terminals is a data transmission method in a system that periodically transmits a message including data to the reception server. There,
The management server assigns a temporary ID, which is a different number, to each terminal in advance for each data transmission cycle, holds it in the terminal management information storage unit, and the data transmission cycle corresponding to the temporary ID for a cycle that guarantees authentication Information is encrypted with a shared secret key with the receiving server, a terminal identification information list in which the encrypted information is arranged in the order of data transmission for each terminal is generated, and first data including the terminal identification information list is associated Process to distribute to terminals,
Each terminal stores the received first data in a terminal identification information storage unit, and at the time of data transmission, reads out the terminal identification information corresponding to data transmission cycle information from the terminal identification information storage unit, and transmits transmission data and the data Encrypting the terminal identification information with a common public encryption key between terminals constituting the group, and transmitting the second data to which the group ID for identifying the group is added to the encrypted data to the receiving server;
The receiving server decrypts the second data with a secret key corresponding to the public encryption key read from an encryption key storage unit that stores an encryption key corresponding to the group ID included in the received second data, If the decrypted terminal identification information is further decrypted with a shared secret key with the receiving server, and the obtained data transmission cycle information corresponds to information indicating the time when the second data is received, It is determined that the terminal that is the source of the two information belongs to the group, and the temporary ID included in the second data and the temporary ID received from each terminal within the period in which the second data is received. The data transmission method according to claim 1, further comprising: determining whether or not there is duplication with an ID. In a configuration in which a plurality of terminals constituting a group, a management server, and a reception server are connected via a network, each of the terminals is a data transmission method in a system that periodically transmits a message including data to the reception server. There,
When the temporary ID included in the second data received by the receiving server detects that there is a duplication within a period of receiving data,
The receiving server transmits the duplicate temporary ID and the group ID, and the data transmission cycle information indicating the duplicate cycle to the management server;
The data according to any one of claims 1 to 3, wherein the management server includes a step of identifying a terminal corresponding to the received temporary ID and the data transmission cycle time by searching a terminal management table. Transmission method. A data transmission system in which a plurality of terminals constituting a group, a management server, and a reception server are connected, and data is transmitted from the plurality of terminals to the reception server,
A temporary ID generation unit that assigns the temporary ID, which is a different number to each terminal, for each data transmission cycle in advance; a terminal management information storage unit that stores the temporary ID and the data transmission cycle information in association with each terminal; A terminal identification in which the temporary ID for the period guaranteeing authentication and the corresponding data transmission period information are encrypted with the shared secret key with the receiving server, and the encrypted information is arranged in the order of data transmission for each terminal. A management server having an encryption unit that generates an information list and distributes the first data including the terminal identification information list to corresponding terminals;
A terminal identification information storage unit for storing the received first data; and at the time of data transmission, the terminal identification information corresponding to the data transmission cycle information is read from the terminal identification information storage unit, and the transmission data, the terminal identification information, A terminal having an encryption unit that encrypts the data with a public encryption key common to the terminals constituting the group and transmits the second data to which the group ID for identifying the group is added to the encrypted data to the receiving server; ,
An encryption key storage unit that stores an encryption key in association with the group ID included in the received second data, and the second data is decrypted with a secret key that is read from the encryption key storage unit and that corresponds to the public encryption key The decryption unit that decrypts the decrypted terminal identification information with a shared secret key with the receiving server, and the obtained data transmission cycle information corresponds to information indicating the time when the second data is received. Then, the group authentication unit that determines that the terminal of the second information transmission source belongs to the group, and the temporary data included in the second data within the period in which the second data is received. A data transmission system comprising: a reception server having an overlap determination unit that determines whether or not there is an overlap between an ID and the temporary ID received from each terminal. In a configuration in which a plurality of terminals constituting a group, a management server, and a reception server are connected via a network, each of the terminals is a data transmission method in a system that periodically transmits a message including data to the reception server. There,
When the temporary ID included in the second data received by the receiving server detects that there is a duplication within a period of receiving data,
The receiving server having a duplication determination unit that transmits the temporary ID and the group ID that are duplicated and the data transmission cycle information that indicates a duplicated cycle to the management server;
6. The data transmission system according to claim 5, further comprising: a management server having means for specifying a terminal corresponding to the received temporary ID and the data transmission cycle time by searching a terminal management table. .   A program for causing a computer to function as the information processing apparatus according to claim 1. A computer-readable recording medium on which the program according to claim 7 is recorded.

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