Encryption method, encryption apparatus, data storage distribution apparatus and data delivery system

• US 20060056625A1
• Filed: 09/09/2005
• Published: 03/16/2006
• Est. Priority Date: 09/10/2004
• Status: Active Grant

• Current Assignee: Hitachi Kokusai Electric Incorporated (Hitachi, Ltd.)
• Original Assignee: Hitachi Kokusai Electric Incorporated (Hitachi, Ltd.)
• Inventors: Nakabayashi, Sumie, Kuwabara, Munemitsu, Yaegashi, Kazuhito, Usami, Hirotake
• Granted Patent: US 7,636,439 B2
• Time in Patent Office: Days
• US Class Current: 380/46
• CPC Class Codes: H04L 2209/30 Compression, e.g. Merkle-Damgard construction
• CPC Class Codes: H04L 2209/601 Broadcast encryption
• CPC Class Codes: H04L 9/0662 with particular pseudorandom sequence generator
• CPC Class Codes: H04L 9/0894 Escrow, recovery or storing of secret information, e.g. secret key escrow or cryptographic key storage

Abstract

Data to be encrypted is effectively encrypted by a data delivery system for encrypting the data to be encrypted with a transmitting apparatus and decrypting a cipher thereof with a receiving apparatus. In a configuration for encrypting and decrypting the data to be encrypted by using a random number sequence generated by a random number generating portion for generating the random number sequence uniquely decided from an input parameter, the transmitting apparatus generates the input parameter to perform encryption based on metadata of the data to be encrypted while the receiving apparatus generates the input parameter to perform cipher decryption based on the metadata embedded in the data to be encrypted.

Claims

1. An encryption method for encrypting data to be encrypted by using a random number sequence generated by a random number generating unit for generating the random number sequence uniquely decided from an input parameter, comprising the step of:

generating the input parameter based on metadata of the data to be encrypted.

2. The encryption method according to claim 1, further comprising the step of:

embedding the metadata in the data to be encrypted or encrypted data to be encrypted; and

,

wherein, in the case of decrypting the encrypted data to be encrypted, the input parameter is generated based on the embedded metadata.

3. The encryption method according to claim 2, further comprising the step of:

encrypting a data body except a header and metadata of the data to be encrypted.

4. The encryption method according to claim 1, further comprising the step of:

updating the input parameter and initializing the random number generating unit per unit or multiple units of the data to be encrypted.

5. The encryption method according to claim 2, further comprising the step of:

updating the input parameter and initializing the random number generating unit per unit or multiple units of the data to be encrypted.

6. The encryption method according to claim 3, further comprising the step of:

updating the input parameter and initializing the random number generating unit per unit or multiple units of the data to be encrypted.

7. The encryption method according to claim 4, wherein:

the input parameter consists of an initialization vector and an encryption key;

the initialization vector is generated based on the metadata; and

the encryption key is not updated from the one set in advance.

8. The encryption method according to claim 5, wherein:

the input parameter consists of an initialization vector and an encryption key;

the initialization vector is generated based on the metadata; and

the encryption key is not updated from the one set in advance.

9. The encryption method according to claim 6, wherein:

the input parameter consists of an initialization vector and an encryption key;

the initialization vector is generated based on the metadata; and

the encryption key is not updated from the one set in advance.

10. A method of searching for the data encrypted by the encryption method according to claim 3, comprising the step of:

searching for the encrypted data based on the embedded metadata.

11. A data delivery system for encrypting data to be encrypted with a transmitting apparatus and decrypting it with a receiving apparatus, wherein:

the transmitting apparatus comprises;

a random number generating unit for generating a random number sequence uniquely decided from an input parameter;

an input parameter generating unit for generating an input parameter based on metadata of the data to be encrypted;

a metadata embedding unit for embedding the metadata in the data to be encrypted or encrypted data to be encrypted; and

an encrypting unit for encrypting a data body except a header and the metadata of the data to be encrypted by using the random number sequence generated by the random number generating unit, and

the receiving apparatus comprises;

the random number generating unit;

a metadata extracting unit for extracting the metadata from the encrypted data to be encrypted;

an input parameter generating unit for generating the input parameter based on the metadata extracted by the metadata extracting unit; and

a decrypting unit for decrypting the data body except the header and the metadata of the encrypted data to be encrypted by using the random number sequence generated by the random number generating unit.

12. The data delivery system according to claim 11, wherein:

the input parameter is updated and the random number generating unit is initialized per unit or multiple units of the data to be encrypted.

13. An encryption apparatus for encrypting data to be encrypted, comprising:

a random number generating unit for generating a random number sequence uniquely decided from an input parameter;

an input parameter generating unit for generating the input parameter based on metadata of the data to be encrypted;

a metadata embedding unit for embedding the metadata in the data to be encrypted or the encrypted data to be encrypted; and

an encrypting unit for encrypting a data body except a header and the metadata of the data to be encrypted by using the random number sequence generated by the random number generating unit.

14. The encryption apparatus according to claim 13, wherein:

the parameter is updated and the random number generating unit is initialized per unit or multiple units of the data to be encrypted.

15. A data storage distribution apparatus including a storage portion for storing encryption data having its data body encrypted except a header and metadata out of data to be encrypted and having the metadata embedded therein by generating an input parameter based on the metadata of the data to be encrypted and using a random number sequence uniquely decided from the input parameter, wherein:

a search is performed based on the metadata according to a search request of the encryption data of desired conditions from a client and transmits the encryption data meeting the search request to the client.