Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
227 words
A crypt key system comprising a broadcasting station, a database, a receiving apparatus, a data communication apparatus and a user terminal, wherein said database and said broadcasting station are connected with a first communication means; said database and said data communication apparatus are connected with a communication line; said broadcasting station and said receiving apparatus are connected with a radio wave; said receiving apparatus and said user terminal are connected with a second communication means; said data communication apparatus and said user terminal are connected with a third communication means; said database prepares a public-key and a private-key and supplies said public-key to said broadcasting station; said broadcasting station broadcasts said received public-key; said receiving apparatus transmits said public-key that has been received to said user terminal; said user terminal 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; said database 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 via said communication line; and said user transmits the received data to said user terminal to decrypt said data by said secret-key.
Claim 2
Dependent Claim
227 words
A crypt key system comprising a broadcasting station, a database, a receiving apparatus, a data communication apparatus and a user terminal, wherein said database and said broadcasting station are connected with a first communication means; said database and said data communication apparatus are connected with a communication line; said broadcasting station and said receiving apparatus are connected with a radio wave; said receiving apparatus and said user terminal are connected with a second communication means; said data communication apparatus and said user terminal are connected with a third communication means; said database prepares a public-key and a private-key and supplies said public-key to said broadcasting station; said broadcasting station broadcasts said received public-key; said receiving apparatus transmits said public-key that has been received to said user terminal; said user terminal 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; said database 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 via said communication line; and said user transmits the received data to said user terminal to decrypt said data by said secret-key.
Claim 3
Dependent Claim
20 words
A crypt key system according to claim 1 wherein a digital signature of said database is provided on said public-key.
Claim 4
Dependent Claim
18 words
A crypt key system according to claim 1 wherein said first communication means is an online communication means.
Claim 5
Dependent Claim
17 words
A crypt key system according to claim 3 wherein said online communication means is a dedicated line.
Claim 6
Dependent Claim
18 words
A crypt key system according to claim 1 whereto said first communication means is an off-line communication means.
Claim 7
Dependent Claim
17 words
A crypt key system according to claim 5 wherein said off-line communication means is a flexible disc.
Claim 8
Dependent Claim
18 words
A crypt key system according to claim 1 wherein said second communication means is an online communication means.
Claim 9
Dependent Claim
17 words
A crypt key system according to claim 7 wherein said online communication means is a dedicated line.
Claim 10
Dependent Claim
18 words
A crypt key system according to claim 1 wherein said second communication means is an off-line communication means.
Claim 11
Dependent Claim
17 words
A crypt key system according to claim 9 wherein said off-line communication means is a flexible disc.
Claim 12
Dependent Claim
18 words
A crypt key system according to claim 1 wherein said third communication means is an online communication means.
Claim 13
Dependent Claim
17 words
A crypt key system according to claim 11 wherein said online communication means is a dedicated line.
Claim 14
Dependent Claim
18 words
A crypt key system according to claim 1 wherein said third communication means is an off-line communication means.
Claim 15
Dependent Claim
17 words
A crypt key system according to claim 13 wherein said off-line communication means is a flexible disc.
Claim 16
Dependent Claim
147 words
A crypt key system comprising a CATV station, a data managing center, a receiving apparatus, a data communication apparatus, and a user terminal, wherein a public-key of a user is registered with said data managing center in advance; said data managing center encrypts a public-key of said data managing center by said public-key of each user and generates a digital signature on said encrypted public-key of said data managing center by a private-key of said data managing center; encrypted said public-key of said data managing center and said digital signature of data managing center are sent to said CATV station; said CATV station broadcasts received said encrypted public-key of data managing center and said digital signature; said user decrypts said received encrypted public-key of data managing center by said private-key of said user and recognizes said digital signature by decrypted said public-key of said data managing center.
Claim 17
Dependent Claim
147 words
A crypt key system comprising a CATV station, a data managing center, a receiving apparatus, a data communication apparatus, and a user terminal, wherein a public-key of a user is registered with said data managing center in advance; said data managing center encrypts a public-key of said data managing center by said public-key of each user and generates a digital signature on said encrypted public-key of said data managing center by a private-key of said data managing center; encrypted said public-key of said data managing center and said digital signature of data managing center are sent to said CATV station; said CATV station broadcasts received said encrypted public-key of data managing center and said digital signature; said user decrypts said received encrypted public-key of data managing center by said private-key of said user and recognizes said digital signature by decrypted said public-key of said data managing center.
Claim 18
Dependent Claim
31 words
A crypt key system according to claim 15 wherein uncrypted user identification information of each user is further added to the encrypted public-key of said data managing center to be broadcast.