Title:
DATA TRANSMITTER/RECEIVER, MULTIMEDIA CONTENTS REPRODUCING SYSTEM, PORTABLE MUSIC REPRODUCING SYSTEM, STATIONARY MUSIC REPRODUCING SYSTEM AND PERSONAL COMPUTER
Document Type and Number:
Japanese Patent JP2001119386
Kind Code:
A
Abstract:
To solve a problem that a cipher is easily deciphered since enciphered transfer data become the same code string every time when a key for enciphering is fixed in the case of transferring a specified digital code stream over and over again.
In enciphering equipment and deciphering equipment, a key is updated while using enciphered data. Since the key is updated every time of enciphering, enciphered transfer data become a code string different every time and secrecy of data transfer is improved.
Inventors:
KATAYAMA DAIRO
OGAWA TOMOTERU
SERIKAWA MITSUHIKO
OGAWA TOMOTERU
SERIKAWA MITSUHIKO
Application Number:
JP29963499A
Publication Date:
April 27, 2001
Filing Date:
October 21, 1999
Export Citation:
Assignee:
MATSUSHITA ELECTRIC IND CO LTD
International Classes:
G11B20/10; H04L9/08; (IPC1-7): H04L9/08; G11B20/10
Attorney, Agent or Firm:
Fumio Iwahashi (2 others)
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