DATA PROCESSING APPARATUS, DATA PROCESSING SYSTEM, AND METHOD FOR CONTROLLING THE SAME

• US 20110271121A1
• Filed: 04/26/2011
• Published: 11/03/2011
• Est. Priority Date: 04/28/2010
• Status: Active Grant

• Current Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Original Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Inventors: Imamoto, Yoshiharu
• Granted Patent: US 8,543,840 B2
• Time in Patent Office: Days
• US Class Current: 713/193
• CPC Class Codes: G11B 20/0021 involving encryption or decryption of contents recorded on or reproduced from a record carrier
• CPC Class Codes: G11B 2220/218 Write-once discs

Abstract

A data processing apparatus acquires content, generates an encryption key by using an initial value written in an unwritten memory block in a write-once recording medium, encrypts the content by using the encryption key, and writes to the write-once recording medium the encrypted content and an address table for identifying the memory block storing the initial value used for generating the encryption key.

Claims

1. A data processing system including a media writing apparatus and a media destruction apparatus,

wherein the media writing apparatus comprises:

an acquisition unit configured to acquire content;

an encryption unit configured to generate an encryption key by using an initial value written in an unwritten memory block in a write-once recording medium, and to encrypt the content by using the encryption key; and

a writing unit configured to write to the write-once recording medium the encrypted content and an address table for identifying the memory block storing the initial value used for generating the encryption key, and

wherein the media destruction apparatus comprises;

a writing unit configured to change the initial value written in the memory block identified by the address table to a different data value, to prevent the encryption key from being generated.

2. A data processing apparatus capable of reading and writing data from/to a write-once recording medium, the data processing apparatus comprising:

an acquisition unit configured to acquire content;

an encryption unit configured to generate an encryption key by using an initial value written in an unwritten memory block in the write-once recording medium, and to encrypt the content by using the encryption key; and

a writing unit configured to write to the write-once recording medium the encrypted content and an address table for identifying the memory block storing the initial value used for generating the encryption key,

wherein the writing unit changes the initial value written in the memory block identified by the address table to a different data value, to prevent the encryption key from being generated.

4. A computer-readable storage medium storing a program which is read out and executed by a computer so as to cause the computer to function as units of the data processing apparatus of claim 2.

3. A method for controlling a data processing apparatus capable of reading and writing data from/to a write-once recording medium, the method comprising:

acquiring content;

generating an encryption key by using an initial value written in an unwritten memory block in the write-once recording medium, and encrypting the content by using the encryption key;

writing to the write-once recording medium the encrypted content and an address table for identifying the memory block storing the initial value used for generating the encryption key; and

changing the initial value written in the memory block identified by the address table to a different data value, to prevent the encryption key from being generated.

5. A data processing system including a media writing apparatus and a media destruction apparatus,

wherein the media writing apparatus comprises:

an acquisition unit configured to acquire content;

an encryption unit configured to identify N unwritten memory blocks in a write-once recording medium, to change an initial value in M memory blocks out of the N memory blocks to a different data value, to generate an encryption key by using a data group written in the N memory blocks, and to encrypt the content by using the encryption key; and

a writing unit configured to write to the write-once recording medium the encrypted content and an address table for identifying the N memory blocks used for generating the encryption key, and

wherein the media destruction apparatus comprises;

a writing unit configured to change an initial value in (N−

M) unwritten memory blocks out of the N memory blocks identified by the address table to a different data value, to prevent the encryption key from being generated.

6. A data processing apparatus capable of reading and writing data from/to a write-once recording medium, the data processing apparatus comprising:

an acquisition unit configured to acquire content;

an encryption unit configured to identify N unwritten memory blocks in the write-once recording medium, to change an initial value in M memory blocks out of the N memory blocks to a different data value, to generate an encryption key by using a data group written in the N memory blocks, and to encrypt the content by using the encryption key; and

a writing unit configured to write to the write-once recording medium the encrypted content and an address table for identifying the N memory blocks used for generating the encryption key,

wherein the writing unit changes an initial value in (N−

M) unwritten memory blocks out of the N memory blocks identified by the address table to a different data value, to prevent the encryption key from being generated.

8. A computer-readable storage medium storing a program which is read out and executed by a computer so as to cause the computer to function as units of the data processing apparatus of claim 6.

7. A method for controlling a data processing apparatus capable of reading and writing data from/to a write-once recording medium, the method comprising:

acquiring content;

identifying N unwritten memory blocks in the write-once recording medium, changing an initial value in M memory blocks out of the N memory blocks to a different data value, generating an encryption key by using a data group written in the N memory blocks, and encrypting the content by using the encryption key;

writing to the write-once recording medium the encrypted content and an address table for identifying the N memory blocks used for generating the encryption key; and

changing an initial value in (N−

M) unwritten memory blocks out of the N memory blocks identified by the address table to a different data value, to prevent the encryption key from being generated.