JP2015023375A - Data collection system, data collection method, gateway device and data compaction system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress processing load related to signature collation in a data collection server, by preventing alteration of data due to spoofing of a gateway device.SOLUTION: A plurality of signature data in the same group are superposed, and compaction data and compaction signature are transmitted from a gateway device representing its group to a data collection server. Furthermore, a signature is created using a signature key of different value in each gateway device.

Description

  The present invention relates to a technique for collecting data.

  There is a data collection system that collects data of digital home appliances inside and outside the home via a wide area network. The conventional configuration is shown in FIG. The gateway device 1 temporarily receives data from digital home appliances and sensor devices installed inside and outside the home, encrypts the data, and transmits the data to the data collection server 3 via the IP network 5 such as the Internet.

  As such encryption and security technology associated therewith, checksum, CRC (Cyclic Redundancy Check), message digest (hash), message authentication code, or digital signature (hereinafter referred to as signature) is used (Non-Patent Document). 1-4).

“Computation of the Internet Checksum via Incremental Update”, RFC1642, May 1994 “Cyclic Redundancy Check”, Hacker ’s Delight (2nd Edition) Chapter 14 “US Secure Hash Algorithms”, RFC6234, May 2011 “Digital Signature Standard”, National Institute of Standards and Technology, FIPS PUB 186-3

  However, even if the above-mentioned security technology is used, detection of data falsification (modification / deletion of data contents / mixing of illegal data) (data integrity verification) and detection of impersonation of the gateway device (data authentication) (First problem).

  For example, since the checksum value, CRC value, and message digest value are simply data for verifying the integrity of the data, it cannot be guaranteed from the data that the checksum value, CRC value, and message digest value are generated by a valid gateway device. Data tampering due to device impersonation cannot be detected.

  In the case of the message authentication method, since the common key is not used in the increment calculation after the message authentication code is first generated, data tampering due to the impersonation of the gateway device cannot be detected in the same manner.

  In the case of the digital signature method, the data integrity verification and the data authentication can both be achieved by adopting the public key method. However, since a large number of public keys corresponding to all gateway devices are acquired and the digital signatures are decrypted, the processing in the data collection server becomes complicated and the data verification load becomes extremely high.

  Furthermore, since data and signatures are transmitted from millions to tens of millions of gateway devices, respectively, the data reception load and signature verification load on the data collection server become very high (second). Task).

  The present invention has been made in view of the above circumstances, and it is an object of the present invention to prevent data falsification due to spoofing of a gateway device and to suppress a processing load related to signature verification or the like in a data collection server.

  The data collection system according to claim 1 includes a plurality of gateway devices that respectively relay data from each inner communication network, and a data collection server that collects the plurality of data via the outer communication network. In the data collection system, the gateway device includes signature key storage means for storing a signature key having a different value in each gateway device, collection target data transmitted from a gateway device in a group to which the gateway device belongs, and the collection target data A data receiving means for receiving the signature data, and a signature key from the signature key storage means, and generating signature data of the data to be collected transmitted from the inner communication network using the signature key A signature aggregating means for superimposing the received signature data, and combining the collection target data with the received collection target data A data aggregating unit that combines the data in a form that maintains the data, and a data transmission unit that transmits the aggregated collection target data and the aggregated signature data aggregated by the combination and the superposition to gateway devices other than the gateway device in the same group, The data collection server includes: a signature key management unit that manages a copy of each signature key stored in each of the plurality of gateway devices; and the aggregated collection target data and the aggregated data from the gateway device representing the group Whether the signature receiving data is received by using the data receiving means for receiving the signature data, the copy of the signature key of the gateway device belonging to the group and the aggregated collection target data, and whether the signature data matches the received aggregated signature data And a data determining means for determining whether or not.

  The data collection system according to claim 2 is the data collection system according to claim 1, wherein the signature aggregating unit uses signature data transmitted from a gateway device in the group as a signature key, and the signature key and the self The summary signature data is generated using the collection target data and the signature key of the device.

  The data collection method according to claim 3, wherein data is performed by a plurality of gateway devices that respectively relay data from each inner communication network and a data collection server that collects the plurality of data via the outer communication network. In the collection method, the gateway device stores a signature key storage step for storing a signature key having a different value in each gateway device in the signature key storage unit, and collection target data transmitted from the gateway device in the group to which the gateway device belongs. A data receiving step for receiving signature data of the collection target data; and a signature key of the own collection target data acquired from the inner communication network using the signature key obtained from the signature key storage unit A signature aggregation step of generating data and superimposing the received signature data; and receiving the data to be collected A data aggregation step for combining the collection target data in a form maintaining the combination order, and transmitting the combined collection target data and the aggregate signature data aggregated by the combination and the superposition to gateway devices other than the gateway device in the same group. A data transmission step, wherein the data collection server manages a copy of each signature key stored in each of the plurality of gateway devices, and the aggregation from the gateway device representing the group A data receiving step for receiving the data to be collected and the aggregated signature data; a copy of the signature key of the gateway device belonging to the group; and the signature data for verification using the aggregated data to be collected, and the received aggregated signature A data determination step for determining whether or not the data matches, And it is required to.

  The data collection method according to claim 4 is the data collection method according to claim 3, wherein the signature aggregation step uses signature data transmitted from a gateway device in the group as a signature key, and the signature key and the self The summary signature data is generated using the collection target data and the signature key of the device.

  The gateway device according to claim 5 stores a signature key having a value different from that of other gateway devices in the gateway device that relays data from the inner communication network to the data collection server via the outer communication network. A signature key storage means, a data receiving means for receiving signature data of the collection target data and the collection target data transmitted from the gateway device in the group to which the signature belongs, and a signature key from the signature key storage means, Generating signature data of own collection target data transmitted from an inner communication network using the own signature key, and superimposing the received signature data on the received signature data; and Data aggregating means for combining the received collection target data in a form that maintains the combination order; and the aggregated collection target data and collection aggregated by the combination and the superposition. Data transmission means for transmitting the signature data to the gateway device other than the gateway device in the same group, and summarized in that with.

  The gateway device according to claim 6 is the gateway device according to claim 5, wherein the signature aggregating unit uses signature data transmitted from a gateway device in a group as a signature key, and collects the signature key and the own device. The gist of the present invention is to generate the aggregate signature data using target data and the signature key of itself.

  The data aggregation program according to claim 7 stores a signature key having a value different from that of other gateway devices in a gateway device that relays data from the inner communication network to the data collection server via the outer communication network. Signature key storage processing stored in the means, data reception processing for receiving the collection target data and signature data of the collection target data transmitted from the gateway device in the group to which it belongs, and signature from the signature key storage means A signature aggregating process for acquiring a key, generating signature data of the data to be collected transmitted from an inner communication network using the signature key, and superimposing the signature data on the received signature data; Data aggregation processing for combining the collection target data with the received collection target data in a form that maintains the combination order, and the aggregated collection aggregated by the combination and the superposition And summarized in that to execute a data transmission process of transmitting the aggregated signature data and target data to the gateway device other than the gateway device in the same group, the.

  The data aggregation program according to claim 8 is the data aggregation program according to claim 7, wherein the signature aggregation processing uses signature data transmitted from a gateway device in a group as a signature key, and the signature key and the self The summary signature data is generated using the collection target data and the signature key of the device.

  According to the present invention, since a plurality of signature data in the same group are overlapped, it is possible to save time and effort for verifying the signatures of the individual signature data, thereby reducing the processing load related to signature verification in the data collection server. In addition, since the data collection server receives the aggregated collection target data and the aggregated signature data from the gateway device representing the group, the processing load related to data reception at the data collection server can be reduced. Furthermore, since the signature data of the data to be collected is generated using the signature key having a different value in each gateway device, it is possible to prevent data from being falsified due to the spoofing of the gateway device.

  According to the present invention, falsification of data due to spoofing of the gateway device can be prevented, and the processing load related to signature verification and the like in the data collection server can be reduced.

It is a figure which shows the logical connection structure of a data collection system. It is a figure which shows the functional block structure of a gateway apparatus. It is a figure which shows the functional block structure of a data collection server. It is a flowchart which shows the processing operation of a signature production | generation part. It is a figure which shows the image of data aggregation and signature aggregation. It is a sequence diagram which shows the processing operation of a data collection system. It is a figure which shows the connection structure of the conventional data collection system.

  The present invention forms a group with a plurality of gateway devices using P2P (Peer to Peer) technology, etc., and sequentially aggregates data and signatures into a small number of gateway devices by a bucket relay system (data aggregation, signature aggregation) After that, the data and the signature are transmitted from the gateway device (representative gateway device) to the data collection server 3.

  In addition, the signature transmitted from another gateway device is used as a signature key, a signature for the aggregated data is generated using a signature key obtained by superimposing the signature key and its own signature key, and the signature is used as the aggregate signature. It is said.

  By providing these characteristics, processing load related to signature verification and the like in the data collection server is reduced.

  Further, each gateway device generates a signature using a signature key having a different value. By providing this feature, it is possible to prevent data falsification due to spoofing of the gateway device.

  Hereinafter, an embodiment for carrying out the present invention will be described with reference to the drawings.

[Overall configuration of data collection system]
FIG. 1 is a diagram showing a logical connection configuration of the data collection system according to the present embodiment. This data collection system includes a plurality of gateway devices 1 that relay data from an internal IP network such as a LAN, and a data collection server 3 that collects the plurality of data via an external IP network 5 such as the Internet. Composed.

  Each gateway device 1 is arranged in each home, and by using P2P technology or the like, gateway devices (1) 1a to gateway devices (3) 1c belonging to group A are logically connected in series. Similarly, gateway devices (4) 1d to (6) 1f belonging to B are connected in series.

[Gateway device functions]
Next, functions of the gateway device 1 will be described in detail. FIG. 2 is a diagram illustrating a functional block configuration of the gateway device 1. The gateway device 1 mainly includes a data reception unit (1) 11, a data storage unit 12, a data encryption unit 13, a signature key storage unit 14, a signature generation unit 15, a data transmission unit 16, and data It is comprised with the receiving part (2) 17. Hereinafter, each part will be described.

  The data receiving unit (1) 11 includes observation / measurement data observed / measured by a digital home appliance or a sensor device inside or outside the home via a narrow-area IP network such as a wired / wireless LAN, or the device by a user. It is a functional part that receives data (collection target data) such as setting data set in.

  The data storage unit 12 is a storage unit such as a memory or a hard disk that stores the data received by the data receiving unit (1) 11 in a readable manner.

The data encryption unit 13 is a functional unit that reads data from the data storage unit 12 and encrypts it with the public key of the data collection server 3. In addition, when encrypted data M ₁ is received from another gateway device 1, the encrypted data M ₂ is combined with the data M ₁ , and at least the order in which the data is combined is maintained. It is also a functional unit that generates aggregated data (data aggregation) in a form.

  The signature key storage unit 14 is a storage unit that stores a signature key k for generating a signature from the data M in the data storage unit 12. Each gateway device 1 holds signature keys k having different values with the same number of bits. The gateway device 1 may be held in advance, or may be transmitted from a predetermined server when the gateway device 1 is connected to the network. The gateway device 1 holds the signature key k so that it can be read only by a specific user authority, and is not shared with other gateway devices 1 except for the data collection server 3.

  The signature generation unit 15 reads out the data M from the data storage unit 12 and also reads out the signature key k from the signature key storage unit 14, and the signature of the data M from the signature key k (data integrity verification and data authentication are possible) This is a functional unit that generates a code value).

  In addition, when the signature generation unit 15 receives a signature from another gateway device 1, the signature generation unit 15 is also a functional unit that generates (signature aggregation) an integrated signature in which the generated signature is superimposed on the signature. Further, the received signature is a signature key k ', and is a functional unit that generates an aggregate signature using the signature key k', its own data M, and its own signature key k.

  The data transmission unit 16 uses the data / aggregated data encrypted by the data encryption unit 13 and the signature data / aggregated signature data generated by the signature generation unit 15 as a gateway device 1 in the same group as its own gateway device 1. (When data is received from another gateway device 1, it is a functional unit that transmits the data to the gateway device 1 other than the gateway device 1).

  The data receiving unit (2) 17 is a functional unit that receives encrypted data / aggregated data and signature data / aggregated signature data from another gateway device 1 in the group to which the data receiving unit (2) 17 belongs.

  The function of the gateway device 1 has been described above. These functional units are included in all gateway devices (1) 1a to (6) 1f. As a group formation method, the same group formation or transmission destination search may be realized using an existing groupware function based on P2P, or the identification information of each group and the gateway device belonging to each group A group list in which one identifier is associated may be used.

[Data collection server functions]
Next, the function of the data collection server 3 will be described in detail. FIG. 3 is a diagram showing a functional block configuration of the data collection server 3. The data collection server 3 mainly includes a data receiving unit 31, a signature key management unit 32, and a data integrity verification / authentication unit 33. Hereinafter, each part will be described.

  The data receiving unit 31 is a functional unit that receives aggregated data and aggregated signature data in each group from the gateway device (3) 1c and gateway device (4) 1d representing each group.

  The signature key management unit 32 is a functional unit that stores and manages a copy of each signature key stored in each gateway device 1.

  The data integrity verification / authentication unit 33 calculates a signature for verification in each group using a copy of each signature key of the gateway device group belonging to each group and the received aggregated data, and compares the signature with the received aggregated signature. Thus, it is a functional unit that determines the detection of data falsification (data integrity verification) and the detection of impersonation of the gateway device 1 (data authentication) based on the comparison result of match / mismatch.

  The function of the data collection server 3 has been described above. The data collection server 3 manages the IP addresses and MAC addresses of all gateway devices 1 and other information necessary for communication, and can communicate with the gateway device 1 mutually.

[About the function (details) of the signature generator]
Next, the signature generation unit 15 of the gateway device 1 will be described in further detail.

Incremental calculation is possible in the error detection method using codes in checksum, CRC, and message digest (hash). That is, f (m ₁ | m ₂ ) = f ′ (f (m ₁ ), m ₂ ) is established for the _two data m ₁ and m ₂ . “|” Represents a connection.

In other words, the output of the function f for connection of the data m ₁ and the data m _2, so that the same output is obtained by the result of the function f and the data m ₂ for the data-only m _1.

  Therefore, when a tree-like overlay network is constructed by a plurality of gateway devices 1 (see FIG. 1), the data aggregated increases toward the upstream of the tree, but it is not necessary to generate a signature from the entire aggregated data. Since the signature can be generated from the signature M and the combined data M, the amount of calculation in each gateway device 1 can be suppressed.

  Hereinafter, a signature generation method and an aggregation method using CRC as an example will be described. FIG. 4 is a flowchart showing the processing operation of the signature generation unit 15.

  First, data is acquired from the data storage unit 12, and the data is set to m (step S101). Then, it is determined whether encrypted data / aggregated data and signature data / aggregated signature data are received from another gateway device 1 (step S102).

  If such data has not been received, the signature key is acquired from the signature key storage unit 14 and set to k (step S103), and the signature C (m, k) of the data m is generated using the signature key k by CRC (step S103). Step S104).

  Here, a method for generating the signature C (m, k) will be described. In the CRC bit string, each digit of the bit string can be regarded as a coefficient of a polynomial of variable x. The coefficient is 0 or 1, and the calculation of the coefficients of the same order follows the calculation of the finite field GF (2).

Addition and subtraction in {0, 1} are equivalent and equivalent to exclusive OR. When the data m and the signature key k are handled as a polynomial of the variable x, the CRC calculation for the data m and the signature key k can be defined as follows when expressed as C (m, k).

  Therefore, the signature C (m, k) is calculated using this equation (1). P is a generator polynomial for variable x in CRC. The symbols | m | and | P | mean the number of bits of the data m and the generator polynomial P, respectively.

  On the other hand, if data is received from another gateway device 1 in the determination in step S102, the received data is M ′, the signature is the signature key k ′ (step S105), and is obtained by CRC in step S101. A temporary signature C (m, k ′) is generated using its own data m and the signature key k ′ (step S106).

The signature key k ′ is a signature for the received data M ′. When the signature key used for the signature is expressed as K, “k ′ = C (M ′, K)”. When the temporary signature C (m, k ′) is expanded using the equation (1), it becomes C (M, K) as in the equation (2), so that the temporary signature C (m, k ′) It can be seen that the signature using the signature key K for the aggregated data M (= M′x ^{| m |} + m) obtained by concatenating the data M ′ received from the gateway device 1 and its own data m is found to match.

  That is, a temporary signature for the aggregated data M obtained by concatenating the data M ′ and the data m can be generated from the signature key k ′ and the own data m. Regardless of the size of the received data M ′, the provisional signature of the aggregated data including the data M ′ is created only from its own data m, so that the amount of computation in the gateway device 1 can be suppressed.

Thereafter, the signature key k is obtained from the signature key storage unit 14, (kx ^{| M |} mod P) is calculated, and the calculated value k (P) is added to the temporary signature C (m, k '). Then, the addition result is used as an aggregate signature (step S107).

  As can be seen from the equation (3), the calculation result of step S107 is received from the other gateway device 1 with respect to the aggregated data M obtained by concatenating its own data m to the data M ′ received from the other gateway device 1. The signature C matches the signature C (M, K + k) generated by using the signature key obtained by superimposing the signature key K used for the signed signature and the signature key k of itself.

  The gateway device 1 also transmits the number of bits of aggregated data to be transmitted. Therefore, the number of bits of | M | in Expression (3) is calculated by adding the number of bits of aggregated data M ′ received from another gateway device and the number of bits of its own data m.

  The signature generation method and aggregation method have been described above. For reference, FIG. 5 shows an image of data aggregation and signature aggregation.

[Operation of data collection system]
Next, the processing operation of the data collection system will be described. FIG. 6 is a sequence diagram showing the processing operation of the data collection system. Here, the gateway device group of group A will be described, and gateway device (2) 1b is assumed to be a representative gateway device of group A.

First, by the gateway device (1) 1a, data M ₁ observed like at home and out of digital appliances and the like are acquired from the data storage unit 12a, the number of bit data M ₁ is a L (step S201).

Next, the gateway device (1) 1a, since data is not received from the other gateway device 1, the signature generation unit 15a, a signature key k ₁ itself is obtained from the signature key storage unit 14a, the formula (1 ), A signature C (M ₁ , k ₁ ) is generated from the data M ₁ and the signature key k ₁ by CRC (step S202).

Next, the data encryption unit 13a generates encrypted data E (M ₁ ) obtained by encrypting the data M ₁ with the public key of the data collection server 3 (step S203).

  The public key distribution method by the data collection server 3 is arbitrary. It may be sent to a specific distribution destination according to the existing SSL protocol, or may be sent arbitrarily to all gateway devices 1.

Next, the data transmission unit 16a, to the same gateway device belonging to the group A (2) 1b, and the number of bits of data _{M 1} L, and the signature _{C (M 1, k 1)} , the encrypted data E (M ₁ ) is transmitted (step S204).

Then, by the gateway device (2) 1b, similarly observed such data M ₂ is obtained from the data storage unit 12b, a the number of bit data M ₁ and the received number of bits of the data M ₂ L is added L ′ (step S205).

Next, since the gateway device (2) 1b has received data from the other gateway device (1) 1a, the signature generation unit 15b converts the received signature C (M ₁ , k ₁ ) into the signature key k ′. The aggregated signature C ′ is generated from the data M ₂ , the signature key k ′, and the signature key k _{2 of} itself using the equation (4) that is the CRC similar to the equation (3) (step S 206).

Next, the data encryption unit 13b generates encrypted data E (M ₂ ) obtained by encrypting the data M ₂ with the public key of the data collection server 3, and the received encrypted data E (M ₁ ) has a list format. (Step S207).

Next, the total number of bits L ′, the aggregated signature C ′, and the encrypted data E (M ₁ ) and E (M ₂ ) are transmitted to the data collection server 3 by the data transmission unit 16b ( Step S208).

  Since the signature aggregation process and the data aggregation process can be executed independently, the data aggregation process (step S207) may be executed first, and then the book title aggregation process (step S206) may be executed. .

Thereafter, copy the data collecting server 3, when they each data is received via the IP network 5, the data integrity verification and authentication unit 33, a gateway device (1) 1a belonging to the group A of signature key k ₁ And a copy of the signature key k ₂ of the gateway device (2) 1b are acquired from the signature key management unit 32, and a verification key K (= k ₁ + k ₂ ) in which the two are superimposed is calculated (step S209). ).

Next, the data integrity verification / authentication unit 33 decrypts the received encrypted data E (M ₁ ) and E (M ₂ ) with its own private key, and concatenates them together with the aggregated data M and the verification data. CRC (verification signature C (M, K)) is obtained using the key K of (1).

Finally, the data integrity verification / authentication unit 33 compares the obtained CRC (verification signature) with the value of the received aggregate signature C ′. Here, the expression (4) of the aggregated signature C ′ obtained previously indicates that the aggregated data M is a concatenation of the data M ₁ and the data M ₂ , and L ′ = | M ₁ | + | M ₂ | Therefore, when the logics of the equations (1) to (3) are expanded, the equation (5) can be developed.

That is, if no data falsification has occurred, the aggregate signature C ′ completely matches the CRC (verification signature) obtained from the aggregate data M and the verification key K (= k ₁ + k ₂ ). become.

  Therefore, if they match, it is detected that the data is not falsified (data integrity verification), and that the gateway device 1 is not impersonated (data authentication). On the other hand, if they do not match, it is detected that the data has been falsified due to impersonation of any gateway device 1 (step S211).

  In particular, data integrity verification can be naturally verified from the match / mismatch of these two values. On the other hand, since each gateway device 1 holds a signature key having a different value for data authentication, it is naturally possible to similarly authenticate from the match / mismatch of these two values.

  If the two do not match, if individual digital signatures are also collected, it can be verified individually and the illegal part can be identified. Although verification processing using a digital signature is expensive, the overall processing load can be reduced by performing individual verification only when detecting whether or not data has been tampered with.

[Example of attack detection by impersonation]
Finally, an example of detecting data falsification will be described. Attacker is the device that impersonates.

(Pattern 1)
Assume that the attacker falsifies the data M to the data M ′. In this case, the data collection server 3 uses the received signature C (M, k) and data M ′ and the signature key k managed by the data collection server 3 so that C (M, k) ≠ C (M ′, k). Can detect tampering.

  Here, the attacker can obtain the correct value of C (M, k), but in order to produce data M ′ that outputs the correct value, it is necessary to know the signature key k. There is. However, since the signing key k is information managed only by the legitimate gateway device 1 and the attacker cannot know the signing key k, C (M ′, k) equivalent to C (M, k). Is difficult to generate. However, data M ′ in which C (M, k) = C (M ′, k) exists theoretically, but it is actually difficult to intentionally create data M ′.

(Pattern 2)
Assume that the attacker falsifies the data M to the data M ′ and further rewrites C (M, k) to C (M ′, k ′). In this case, the data collection server 3 determines that C (M ′, k ′) ≠ C (M ′, k) from the received signature C (M ′, k ′) and data M ′ and the signature key k managed by itself. Therefore, alteration of data can be detected. Like the pattern 1, since the attacker does not have the correct signature key k, it is difficult to generate the correct signature C (M, k).

(Pattern 3)
Assume that an attacker forges data M ′ in which illegal data m is mixed into data M, and further rewrites C (M, k) to C (M ′, k). In this case, since C (M ′, k) received by the data collection server 3 is not superposed with the signature key k of the gateway device 1 masqueraded by the attacker, the data M ′ and the data collection server 3 manage them. The signature value obtained from the signature key k does not match C (M ′, k). Therefore, the data collection server 3 can detect tampering.

  The data collection system according to this embodiment has been described above. In the present embodiment, each gateway device 1 has been described with respect to a case where each gateway device 1 encrypts and transmits and aggregates its own data. However, raw data may be transmitted and aggregated without being encrypted.

  According to the present embodiment, since a plurality of signatures in the same group are superimposed (aggregated), it is possible to save the effort of verifying the signatures of the individual signature data. Can be reduced. In particular, since the superimposition is performed by a simple algorithm such as Expression (3), the processing load on the data collection server 3 is not increased even if aggregation is performed.

  Further, according to the present embodiment, the data collection server 3 receives the aggregated data and the aggregated signature from the gateway device 1 representing the group, so that the processing load related to data reception at the data collection server 3 can be reduced.

  Furthermore, according to the present embodiment, each gateway device 1 generates a signature by using a signature key having a different value. Therefore, it is possible to prevent falsification of data due to impersonation of the gateway device 1, and to verify data integrity and data Both authentication can be achieved. Thereby, illegal data can be eliminated.

  Finally, the gateway device 1 and the data collection server 3 described in the present embodiment can be realized by a computer. It is also possible to construct each operation of these components as a program, install it in a computer and execute it, or distribute it via a communication network.

DESCRIPTION OF SYMBOLS 1 ... Gateway apparatus 11 ... Data receiving part (1)
12 ... Data storage unit 13 ... Data encryption unit (data aggregation means)
14 ... Signature key storage unit 15 ... Signature generation unit (signature aggregation means)
16: Data transmission unit (data transmission means)
17: Data receiving section (2) (data receiving means)
3 ... Data collection server 31 ... Data reception unit 32 ... Signature key management unit (signature key management means)
33 ... Data integrity verification / authentication section (data judgment means)
5 ... IP network S101-S107, S201-S211 ... step

Claims (8)

In a data collection system comprising a plurality of gateway devices that respectively relay data from each inner communication network and a data collection server that collects the plurality of data via the outer communication network,
The gateway device is
A signature key storage means for storing a signature key having a different value in each gateway device;
Data receiving means for receiving the data to be collected transmitted from the gateway device in the group to which it belongs and the signature data of the data to be collected;
A signature that obtains a signature key from the signature key storage unit, generates signature data of the data to be collected transmitted from an internal communication network using the signature key, and superimposes the signature data on the received signature data An aggregation means;
A data aggregating means for combining the own collection target data with the received collection target data in a form maintaining a combination order;
Data transmission means for transmitting aggregated collection target data and aggregated signature data aggregated by the combination and superposition to a gateway device other than the gateway device in the same group, and
The data collection server
Signature key management means for managing a copy of each signature key stored in each of the plurality of gateway devices;
Data receiving means for receiving the aggregated collection target data and the aggregated signature data from the gateway device representing the group;
Data determination means for generating signature data for verification using a copy of the signature key of the gateway device belonging to the group and the aggregated collection target data, and determining whether or not the received aggregated signature data matches;
A data collection system comprising: The signature aggregation means includes
The signature data transmitted from a gateway device in a group is used as a signature key, and the aggregate signature data is generated using the signature key, the own collection target data, and the own signature key. The data collection system according to 1. In a data collection method performed by a plurality of gateway devices that respectively relay data from each inner communication network and a data collection server that collects the plurality of data via an outer communication network,
By the gateway device,
A signature key storage step of storing a signature key having a different value in each gateway device in the signature key storage means;
A data reception step of receiving the collection target data transmitted from the gateway device in the group to which the device belongs and the signature data of the collection target data;
A signature that obtains a signature key from the signature key storage unit, generates signature data of the data to be collected transmitted from an internal communication network using the signature key, and superimposes the signature data on the received signature data An aggregation step;
A data aggregation step of combining the own collection target data with the received collection target data while maintaining a combination order;
A data transmission step of transmitting aggregated collection target data and aggregated signature data aggregated by the combination and superposition to a gateway device other than the gateway device in the same group, and
By the data collection server,
A signature key management step for managing a copy of each signature key stored in each of the plurality of gateway devices;
A data receiving step of receiving the aggregated collection target data and the aggregated signature data from the gateway device representing the group;
A data determination step of generating signature data for verification using a copy of the signature key of the gateway device belonging to the group and the aggregated collection target data, and determining whether or not the received signature data matches the received aggregated signature data;
A data collection method characterized by comprising: The signature aggregation step includes:
The signature data transmitted from a gateway device in a group is used as a signature key, and the aggregate signature data is generated using the signature key, the own collection target data, and the own signature key. 3. The data collection method according to 3. In the gateway device that relays data from the inner communication network to the data collection server via the outer communication network,
Signature key storage means for storing a signature key having a value different from that of the other gateway device;
Data receiving means for receiving the data to be collected transmitted from the gateway device in the group to which it belongs and the signature data of the data to be collected;
A signature that obtains a signature key from the signature key storage unit, generates signature data of the data to be collected transmitted from an internal communication network using the signature key, and superimposes the signature data on the received signature data An aggregation means;
A data aggregating means for combining the own collection target data with the received collection target data in a form maintaining a combination order;
Data transmission means for transmitting aggregated collection target data and aggregated signature data aggregated by the combination and the superposition to a gateway device other than the gateway device in the same group;
A gateway device comprising: The signature aggregation means includes
The signature data transmitted from a gateway device in a group is used as a signature key, and the aggregate signature data is generated using the signature key, the own collection target data, and the own signature key. 5. The gateway device according to 5. To the gateway device that relays data from the inner communication network to the data collection server via the outer communication network,
A signature key storage process for storing a signature key having a value different from that of the other gateway device in the signature key storage unit;
A data reception process for receiving the collection target data transmitted from the gateway device in the group to which it belongs and the signature data of the collection target data;
A signature that obtains a signature key from the signature key storage unit, generates signature data of the data to be collected transmitted from an internal communication network using the signature key, and superimposes the signature data on the received signature data Aggregation processing,
A data aggregation process for combining the own collection target data with the received collection target data in a form that maintains a combination order;
Data transmission processing for transmitting aggregated collection target data and aggregated signature data aggregated by the combination and superimposition to a gateway device other than the gateway device in the same group;
A data aggregation program characterized in that The signature aggregation process includes:
The signature data transmitted from a gateway device in a group is used as a signature key, and the aggregate signature data is generated using the signature key, the own collection target data, and the own signature key. 7. The data aggregation program according to 7.

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