P

Inventor

TAKARAGI KAZUO

JP67 patents

Patents

50 patents
US5315634AMay 24, 1994

Automatic trading method and apparatus

HITACHI LTD270 citations99
US5018196AMay 21, 1991

Method for electronic transaction with digital signature

HITACHI LTD259 citations99
US7061083B1Jun 13, 2006

Semiconductor devices

HITACHI LTD117 citations98
US6873706B1Mar 29, 2005

Processing apparatus, program, or system of secret information

HITACHI LTD102 citations98
US6499105B1Dec 24, 2002

Digital data authentication method

HITACHI LTD174 citations98
US6131162AOct 10, 2000

Digital data authentication method

HITACHI LTD388 citations98
US5465299ANov 7, 1995

Electronic document processing system and method of forming digital signature

HITACHI LTD428 citations98
US5280583AJan 18, 1994

System and method for performing interlocution at a plurality of terminals connected to communication network

HITACHI LTD161 citations98
US6922686B2Jul 26, 2005

Database integration management method and apparatus and processing program, medium therefor

HITACHI LTD121 citations97
US6341349B1Jan 22, 2002

Digital signature generating/verifying method and system using public key encryption

HITACHI LTD102 citations97
US5235641AAug 10, 1993

File encryption method and file cryptographic system

HITACHI LTD259 citations97
US4885788ADec 5, 1989

IC card

HITACHI LTD139 citations97
US7447339B2Nov 4, 2008

Unique code generating apparatus, method, program and recording medium

HITACHI LTD62 citations96
US6592032B1Jul 15, 2003

Control system and method of controlling information written into storage media

HITACHI LTD42 citations96
US6477254B1Nov 5, 2002

Network system using a threshold secret sharing method

HITACHI LTD60 citations96
US6370247B1Apr 9, 2002

Hash value generating method and device, data encryption method and device, data decryption method and device

HITACHI LTD60 citations96
US6141421AOct 31, 2000

Method and apparatus for generating hash value

HITACHI LTD77 citations96
US6122378ASep 19, 2000

Data compression/encryption method and system

HITACHI LTD97 citations96
US6122375ASep 19, 2000

Hash value generating method and device, data encryption method and device, data decryption method and device

HITACHI LTD49 citations96
US6118874ASep 12, 2000

Encrypted data recovery method using split storage key and system thereof

HITACHI LTD255 citations96
US5966448AOct 12, 1999

Cryptographic communication system

HITACHI LTD142 citations96
US5309516AMay 3, 1994

Group cipher communication method and group cipher communication system

HITACHI LTD93 citations96
US5222139AJun 22, 1993

Cryptographic method and apparatus

HITACHI LTD75 citations96
US5144665ASep 1, 1992

Cryptographic communication method and system

HITACHI LTD102 citations96
US5117458AMay 26, 1992

Secret information service system and method

HITACHI LTD111 citations96
US7110545B2Sep 19, 2006

Method and apparatus for symmetric-key encryption

HITACHI LTD62 citations95
US5103479AApr 7, 1992

Encipher method and decipher method

HITACHI LTD45 citations95
US4885777ADec 5, 1989

Electronic transaction system

HITACHI LTD154 citations95
US6157720ADec 5, 2000

Method and apparatus for encrypting data

HITACHI LTD51 citations94
US6714648B2Mar 30, 2004

IC card equipped with elliptic curve encryption processing facility

HITACHI LTD27 citations93
US6466668B1Oct 15, 2002

IC card equipped with elliptical curve encryption processing facility

HITACHI LTD43 citations93
US7210043B2Apr 24, 2007

Trusted computer system

HITACHI LTD21 citations92
US7200682B2Apr 3, 2007

Time stamp generating system

HITACHI LTD21 citations92
US7134021B2Nov 7, 2006

Method and system for recovering the validity of cryptographically signed digital data

HITACHI LTD16 citations92
US6934842B2Aug 23, 2005

Identification code management method and management system

HITACHI LTD32 citations92
US6683956B1Jan 27, 2004

Encrypting conversion apparatus, decrypting conversion apparatus, cryptographic communication system, and electronic toll collection apparatus

HITACHI LTD36 citations92
US6659353B1Dec 9, 2003

Method of checking authenticity of sheet with built-in electronic circuit chip

HITACHI LTD31 citations92
US6311277B1Oct 30, 2001

Method and device for managing computer network

HITACHI LTD42 citations92
US6236729B1May 22, 2001

Key recovery method and system

HITACHI LTD28 citations92
US5218638AJun 8, 1993

Encipher method and decipher method

HITACHI LTD43 citations92
US4982429AJan 1, 1991

Encipher method and decipher method

HITACHI LTD22 citations92
US7305558B1Dec 4, 2007

Digital signing method

HITACHI LTD38 citations91
US7173515B2Feb 6, 2007

RFID tag, and RFID tag-related determining device and method, and management system and method

HITACHI LTD19 citations91
US6816969B2Nov 9, 2004

Digital signature generating method and digital signature verifying method

HITACHI LTD41 citations91
US7298029B2Nov 20, 2007

Semiconductor devices and manufacturing method therefor

HITACHI LTD15 citations84
US7178026B2Feb 13, 2007

Identification code management method and management system

HITACHI LTD11 citations84
US7089388B1Aug 8, 2006

Terminal for use in a system interfacing with storage media

HITACHI LTD11 citations84
US6606385B1Aug 12, 2003

Data encrypting/decrypting conversion methods and apparatuses and data communication system adopting the same

HITACHI LTD14 citations84
US7224796B2May 29, 2007

Pseudorandom number generating apparatus or encryption or decryption apparatus using the same

HITACHI LTD10 citations83
US7138915B2Nov 21, 2006

Handling support method and handling support system

HITACHI LTD12 citations83

Showing the top 50 of 67 patents by PatentIndex Score.