Data processing method and data checking method

• US 20050022093A1
• Filed: 07/13/2004
• Published: 01/27/2005
• Est. Priority Date: 07/23/2003
• Status: Active Grant

• Current Assignee: Sony Corporation (Sony Group Corp.)
• Original Assignee: Sony Corporation (Sony Group Corp.)
• Inventors: Murakoshi, Sho
• Granted Patent: US 7,373,525 B2
• Time in Patent Office: Days
• US Class Current: 714/758
• CPC Class Codes: G06F 11/1004 to protect a block of data words, e.g. CRC or checksum G06F11/1076 takes precedence; security arrangements for protecting computers or computer systems against unauthorized activity G06F21/00
• CPC Class Codes: G06F 21/64 Protecting data integrity, e.g. using checksums, certificates or signatures

Abstract

Cyclic-redundancy-check (CRC) processing is executed on data blocks each having a predetermined data amount, thereby calculating respective CRC values for the data blocks. Furthermore, CRC processing is executed on the respective CRC values a number of times determined according to random numbers that are generated sequentially, thereby generating sig values to be attached respectively to next data blocks.

Claims

1. A data processing method at least comprising the steps of:

calculating a cyclic-redundancy-check value by executing cyclic-redundancy-check processing on a data block having a predetermined data amount; and

executing cyclic-redundancy-check processing a number of times on the cyclic-redundancy-check value to generate a check value that is to be attached to a next data block.

2. The data processing method according to claim 1, wherein the number of times is determined according to random numbers that are generated sequentially, and is changed each time a check value is generated.

3. The data processing method according to claim 1, wherein, in a data area for storing a data block having the predetermined data amount, the data block, a cyclic-redundancy-check value for the data block, and a check value generated from a cyclic-redundancy-check value of a data block that is stored in an immediately preceding data area are stored.

4. A data checking method for checking data in which each data block, having a predetermined data amount, has a cyclic-redundancy-check value and a check value attached thereto, wherein data is checked by comparing a value calculated by executing cyclic-redundancy-check processing a number of times on a cyclic-redundancy-check value attached to a data block with a check value attached to a next data block.

5. The data checking method according to claim 4, wherein the number of times is determined according to random numbers that are generated sequentially, and is changed each time a check value is generated.