EP0719045A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Crypt key system for broadcast programmes
Assignee: Mitsubishi Corp
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Filing: 1995-12-13
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Granted: —
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Expires: 2015-12-13
Abstract
Abstract The invention relates to a crypt key system applicable to a television system, a database system or an electronic commercial transaction system or the like. This system consists of a broadcasting station 11, a database 12, a receiving apparatus 14, a data communication apparatus 15 and a user terminal 18. As a crypt key system, a secret-key cryptosystem, a public-key cryptosystem, and a digital signature system are used. The keys used in the system are either encrypted or remain uncrypted to be supplied by broadcasting. The present invention is effective in the prevention of an unjustified use of the database system, managing copyrights, and in a pay-per-view system and a video-on-demand system. Further, the present invention is effective in realizing an electronic market which uses an electronic data information system.
Inventors
- 👤 Makato Saito
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-28 10:31
CPC Classifications
G; G06; G06Q; G06Q20/00; G06Q20/02; G06Q20/08; G06Q20/085; G06Q20/0855; H; H04; H04N; H04N21/00; H04N21/20; H04N21/25; H04N21/254; H04N21/2543; H04N21/40; H04N21/43; H04N21/437; H04N21/47; H04N21/478; H04N21/47815; H04N21/60; H04N21/61; H04N21/6156; H04N21/63; H04N21/633; H04N21/6332; H04N21/6334; H04N21/63345; H04N21/80; H04N21/83; H04N21/835; H04N21/8358; H04N7/00; H04N7/16; H04N7/167; H04N7/1675; H04N7/173; H04N7/17309
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
278 words
Crypt key system comprising a broadcasting station (1), a database (2), a receiving apparatus (4), a data communication apparatus (5) and a user terminal (8), wherein said database (2) and said broadcasting station (1) are connected with an online communication means such as a dedicated line, or the like or a off-line means such as a flexible disc or the like; said database (2) and said data communication apparatus (5) are connected with a communication line (7) ; said broadcasting station (1) and said receiving apparatus (4) are connected with a radio wave (6); whereas between said receiving apparatus (4) and said user terminal (8) and between said data communication apparatus (5) and said user terminal (8) said are connected with direct online means or with off-line means such as a flexible disc; said database (2) prepares a public-key and a private-key and supplies said public-key to said broadcasting station (1); said broadcasting station (1) broadcasts said received public-key; said receiving apparatus (4) transmits said received public-key to said user terminal (8); said user terminal (8) stores said transmitted public-key; a user encrypts a secret-key of the user by said received public-key and transmits said secret-key at the time of request for the use of data which he desires, to said database (2); said database (2) which has received the request for data use decrypts said secret-key of said user by said private-key and encrypts the data by said decrypted secret-key of said user to transmit the data to said data communication apparatus (5) via said communication line (7); and said user transmits the received data to said user terminal (8) to decrypt said data by said secret-key.
Claim 2
Dependent Claim
20 words
Crypt key system according to claim 1 wherein a digital signature of said database (2) is provided on said public-key.
Claim 3
Dependent Claim
208 words
Crypt key system comprising a CATV station (31) , a charging center, a receiving apparatus (34), a data communication apparatus (35), and a user terminal (38), wherein between said CATV station (31) and said receiving apparatus (34) and between said CATV station (31) and said data communication apparatus (35) are connected with a CATV line (37) ; between said receiving apparatus (34) and said user terminal (38) and between said data communication apparatus (35) and said user terminal (38) are connected with direct online means or with off-line means such as a flexible disc or the like; a user preliminarily registers a public-key of said user with said CATV station (31) or presents said public-key of said user at the time of request for usage; said CATV station (31) encrypts a secret-key which is a use permit key of said CATV (31) station by using said public-key of said user who has requested the usage and also encrypts a television program by said secret-key, to broadcast both via said CATV line (37); and said user receives said encrypted television program and said secret-key with said receiving apparatus (34) and decrypts said secret-key by a private-key corresponding to said public-key for decrypting said television program by said decrypted secret-key.
Claim 4
Dependent Claim
312 words
Crypt key system comprising a CATV station (31), a data managing center (33), a receiving apparatus (34), a data communication apparatus (35) and a user terminal (38), wherein said CATV station (31) and said data managing center (33) are connected with online communication means such as a dedicated line or the like, or off-line means such as a flexible disc or the like; between said CATV station and said receiving apparatus (34) and between said CATV station and said data communication apparatus (35) are connected with a CATV line (37) ; between said receiving apparatus (34) and said user terminal (38) and between said data communication apparatus (35) and said user terminal (38) are connected with direct online means or with off-line means such as a flexible disc or the like; said data managing center (33) supplies a public-key, and a secret-key which is a use permit key for each data to be supplied, to said CATV station (31); said CATV station (31) encrypts said secret-key for each data by said public-key of data managing center (33) to broadcast; a user requests for the use of data by using said data communication apparatus (35) to said data managing center (EE) via said CATV line (37) together with transmitting a public-key of said user; said data managing center (33) encrypts the data by said secret-key for each data, and encrypts said public-key of data managing center (33) by said public-key of said user and transmits encrypted data and encrypted said public-key of data managing center (33) together with a private-key of said data managing center (33) to said user; said user decrypts said encrypted public-key of data managing center (33) by a private-key of said user, decrypts said encrypted secret-key for each data by decrypted said public-key of data managing center (33) and decrypts encrypted data by decrypted said secret-key for each data.
Claim 5
Dependent Claim
27 words
Crypt key system according to claim 4 wherein a digital signature of said data managing center (33) is provided on said public-key of data managing center (33).
Claim 6
Dependent Claim
159 words
Crypt key system comprising a CATV station (31), a data managing center (33), a receiving apparatus (34), a data communication apparatus (35), and a user terminal (38), wherein a public-key of a user is registered with said data managing center (33) in advance; said data managing center (33) encrypts a public-key of said data managing center (33) by said public-key of each user to provide a digital signature on said public-key of data managing center (33) by a private-key of said data managing center (33); said encrypted public-key of said data managing center (33) and said digital signature of data managing center (33) are sent to said CATV station (31); said CATV station (31) broadcasts said received encrypted public-key of data managing center (33) and said digital signature; said user decrypts said received encrypted public-key of data managing center (33) by said public-key of said user and recognizes said digital signature by said decrypted public-key of data control center.
Claim 7
Dependent Claim
31 words
Crypt key system according to claim 6 wherein uncrypted user identification information of each user is further added to the encrypted public-key of said data managing center (33) to be broadcast.
Claim 8
Dependent Claim
115 words
Crypt key system comprising a CATV station (31), a data managing center (33), a receiving apparatus (4), a data communication apparatus (35), and a user terminal (38), wherein a user presents a public-key of said user to said data managing center (33) upon requesting use of the data to said data managing center (33); said data managing center (33) receives the request for data use from said user and encrypts the data requested by said public-key of said user to send to said CATV station (31) ; said CATV station (31) broadcasts said received encrypted data; and said user who receives said broadcast encrypted data decrypts said encrypted data by a private-key of said user.
References Cited (Backward Citations)
No citation records indexed.
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