Method and system for transferring data
A system is provided for improving security during data transfer. A transmitter side transfer controller ( 12 ) divides data to be transferred into a plurality of pieces, removes a portion of data from each piece and encrypts the piece, and uploads each encrypted piece to different relay servers ( 22 ) on the Internet ( 20 ). The transmitter side transfer controller ( 12 ) also provides a receiver side transfer controller ( 12 ) information indicating which piece is uploaded to which relay server ( 22 ) using a secure communication protocol. The data of the fragment removed from each piece is transmitted to the receiver side transfer controller ( 12 ) separately from the encrypted pieces. The receiver side transfer controller ( 12 ) downloads the encrypted pieces each uploaded to the relay server ( 22 ), decodes the encrypted pieces, complements the decoded data with the data of the fragment to restore the state before the removal, and assembles the restored pieces to obtain the original data to be transferred.
1. A data transfer method for transferring data from a source device to a destination device, wherein
the source device divides data to be transferred into a plurality of pieces, determines, for each piece, a relay region to which the piece is to be uploaded, transmits correspondence information indicating the correspondence between each piece and each upload destination relay region to a destination device of the data to be transferred, and uploads each piece to the corresponding upload destination relay region; and
the destination device receives the correspondence information from the source device, downloads, based on the correspondence information, each piece from the relay region to which the piece is uploaded, and integrates downloaded pieces to restore the original data to be transferred.
2. A data transfer method according to claim 1 , wherein the correspondence information is transmitted using a communication system different from that for the uploading and downloading of the pieces.
3. A data transfer method according to claim 1 , wherein
the source device divides the data to be transferred into a plurality of pieces, removes a fragment of data from each piece, uploads the remaining segment to a corresponding relay region, and transmits data of the fragment for each piece to the destination device using a communication system different from that for the uploading of the pieces, and
the destination device receives the data of the fragment for each piece, uses the fragment data to restore each piece downloaded from the relay region to a state having no missing portion, and integrates the pieces.
4. A data transfer method according to claim 3 , wherein
the source device selects a methodology for the removal process for removing a fragment of data from each of the pieces based on a methodology determination algorithm common to the source and destination devices, and
the destination device identifies the methodology for the removal process applied to each piece based on the methodology determination algorithm and restores each piece based on the identified methodology.
5. A data transfer method according to claim 3 , wherein
the source device transmits the data of the fragments to the destination device when the source device detects completion of downloading of all of the pieces constituting the data to be transferred by the destination device.
6. A data transfer method according to claim 1 , wherein
the source device determines encryption parameters corresponding to each piece based on an encryption parameter determination algorithm common to the source and destination devices, encrypts each piece using the determined encryption parameters, and uploads each encrypted piece to the corresponding relay region, and
the destination device identifies the encryption parameters for each piece based on the encryption parameter determination algorithm and decodes each piece based on the identified encryption parameters.
7. A data transmission method for transferring data to a destination device, comprising the steps of:
dividing data to be transferred into a plurality of pieces;
determining, for each piece, a relay region to which the piece is to be uploaded;
transmitting, to the destination device, correspondence information indicating the correspondence between each piece and each relay region to which the piece is to be uploaded; and
uploading each piece to the determined upload destination relay region.
8. A data transmission method according to claim 7 , further comprising the steps of:
removing a fragment of data from each piece after the data to be transferred is divided into a plurality of pieces and uploading the remaining segment to the corresponding relay region; and
transmitting, to the destination device, data of the fragment for each piece using a communication system different from that for the uploading of the pieces.
9. A data transmission method according to claim 8 , wherein
the source device transmits the data of the fragment to the destination device when the source device detects completion of downloading of all of the pieces constituting the data to be transferred by the destination device.
10. A data reception method for receiving data to be transferred which is transferred from a source device, the method comprising the steps of:
receiving, from the source device, correspondence information indicating a relay region to which each piece constituting the data to be transferred is uploaded;
downloading each piece from the relay region to which the piece is uploaded based on the correspondence information; and
integrating the downloaded pieces to restore the original data to be transferred.
11. A data reception method according to claim 10 , further comprising the steps of:
receiving, from the source device, data of the fragment for each piece; and
integrating the pieces downloaded from the relay regions after restoring the pieces to a state having no missing portion using the fragment data.
12. A data transfer system for transferring data from a source device to a destination device, wherein
the source device comprises dividing means for dividing data to be transferred into a plurality of pieces, upload destination determining means for determining, for each piece, a relay region as an upload destination to which the piece is to be uploaded, correspondence information transmitting means for transmitting, to the destination device of the data to be transferred, correspondence information indicating each piece and the upload destination relay region of the piece, and uploading means for uploading each piece to the determined upload destination relay region, and
the destination device comprises correspondence information receiving means for receiving the correspondence information from the source device, downloading means for downloading each piece from the relay region to which the piece is uploaded based on the received correspondence information, and restoring means for integrating the downloaded pieces and restoring the original data to be transferred.
13. A data transfer system according to claim 12 , wherein
the correspondence information is transmitted using a communication system different from that for the uploading and downloading of the pieces.
14. A data transfer system according to claim 12 , wherein
the source device removes a fragment of data from each piece after the data to be transferred is divided into a plurality of pieces, uploads the remaining segment to the corresponding relay region, and transmits, to the destination device, data of the fragment for each piece using a communication system different from that for the uploading of each piece, and
the destination device receives the data of the fragment for each piece, uses the fragment data to restore each piece downloaded from the relay region to a state having no missing portion, and integrates the pieces.
15. A data transfer system according to claim 14 , wherein the source device selects a methodology for the process of removing data from each piece according to a methodology determination algorithm which is common to the source and destination devices, and
the destination device identifies the methodology for the removal process applied to each piece according to the methodology determination algorithm and restores each piece based on the identified methodology.
16. A data transfer system according to claim 14 , wherein
the source device transmits the data of the fragment to the destination device when the source device detects completion of downloading of all of the pieces constituting the data to be transferred by the destination device.
17. A data transfer system according to claim 12 , wherein
the source device determines encryption parameters corresponding to each piece based on an encryption parameter determination algorithm common to the source and destination devices, encrypts each piece using the determined encryption parameters, and uploads the encrypted piece to the corresponding relay region, and
the destination device identifies the encryption parameters for each piece based on the encryption parameter determination algorithm and decodes each piece based on the identified encryption parameters.
18. A data transmitter for transmitting data to a destination device, the transmitter comprising:
dividing means for dividing data to be transferred into a plurality of pieces;
upload destination determining means for determining, for each piece, a relay region as an upload destination to which the piece is to be uploaded;
correspondence notifying means for transmitting, to the destination device of the data to be transferred, correspondence information indicating the correspondence between each piece and the upload destination relay region for the piece; and
uploading means for uploading each piece to the determined upload destination relay region.
19. A data transmitter according to claim 18 , wherein
the correspondence information notifying means establishes a secure communication system with the destination device and transmits the correspondence information via the secure communication system.
20. A data transmitter according to claim 19 , wherein
the uploading means comprises:
fragment removal means for removing a fragment of data from each piece after the data to be transferred is divided into a plurality of pieces and uploading the remaining segment to the corresponding relay region; and
fragment transmitting means for transmitting, to the destination device, the data of the fragment removed from the piece through a communication system other than that used for uploading the piece.
21. A data transmitter according to claim 20 , wherein
the fragment transmitting means transmits the data of the fragment to the destination device when the data transmitter detects completion of downloading of all of the pieces constituting the data to be transferred by the destination device.
22. A data receiver for receiving data to be transferred which is transferred from a source device, the receiver comprising:
correspondence information receiving means for receiving, from the source device, correspondence information indicating a relay region to which each of the pieces constituting the data to be transferred is uploaded;
downloading means for downloading each piece from the relay region to which the piece is uploaded based on the correspondence information; and
restoring means for integrating the downloaded pieces and restoring the original data to be transferred.
23. A data receiver according to claim 22 , further comprising;
fragment receiving means for receiving, from the source device, data of fragments removed from each piece, wherein
the restoring means integrates the pieces after using the data of the fragment received by the fragment receiving means to restore each piece downloaded from the relay region to a state having no missing portion.
24. A data transfer method for transferring data from a source device to a destination device, wherein
the source device divides data to be transferred into a plurality of pieces, removes a fragment of data from each piece, transmits the segment of each piece remaining after the removal process to the destination device, and transmits, to the destination device, the data of the fragment removed from each piece using a communication system other than that used for the data of the piece, and
the destination device receives the remaining segment of each piece after the removal process, receives the data of the fragment removed from each piece, restores the remaining segment of each piece to a state before the removal process using the data of the fragment for each piece, and integrates the restored pieces to restore the original data to be transferred.
25. A data transfer method according to claim 24 , wherein
the source device selects a methodology for the process used for removing data from each piece according to a methodology determination algorithm which is common to the source and destination devices, and
the destination device identifies the methodology for the removal process applied to each piece according to the methodology determination algorithm and restores each piece according to the identified methodology.
26. A data transfer method according to claim 24 , wherein
the source device transmits the data of the fragment to the destination device when the source device detects completion of downloading of all of the pieces constituting the data to be transferred by the destination device.
27. A data transfer system for transferring data from a source device to a destination device, wherein
the source device comprises dividing means for dividing data to be transferred into a plurality of pieces, fragment removal means for removing a fragment of data from each piece, piece transmitting means for transmitting to the destination the segment of each piece remaining after the removal process, and fragment transmitting means for transmitting the data of the fragment removed from each piece to the destination device using a communication system other than that used for transmitting the data of each piece, and
the destination device comprises piece receiving means for receiving the remaining segment of each piece, fragment receiving means for receiving the data of the fragment from each piece, piece restoring means for using the fragment data for each piece to restore the remaining segment to a state before the removal process, and data restoring means for integrating the restored pieces to restore the original data to be transferred.
28. A data transfer system according to claim 27 , wherein
the partial removal means of the source device selects a methodology for the removal process according to a methodology determination algorithm common to the source and the destination, and
the piece restoring means of the destination device identifies the methodology for the removal process applied to each piece according to the methodology determination algorithm and restores each piece according to the identified methodology.
29. A data transfer system according to claim 27 , wherein
the fragment transmitting means of the source device transmits the data of the fragment to the destination device when the source device detects completion of downloading of all of the pieces constituting the data to be transferred by the destination.