US6904522B1
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method and apparatus for secure communication of information between a plurality of digital audiovisual devices
Assignee: KCA Licensing SA
•
Filing: 1999-07-14
•
Granted: 2005-06-07
•
Expires: 2019-07-14
Abstract
Abstract The present invention relates to a method of providing secure communication of information between at least a first and second digital audiovisual device ( 30, 52 ) and characterized in that the first device ( 30 ) communicates to the second device ( 52 ) a certificate Ct(KpubT) comprising a transport public key KpubT encrypted by a management private key KpriMan, the second device ( 52 ) decrypting the certificate using an equivalent management public key KpubMan and thereafter using the transport public key KpubT to encrypt information sent to the first device, the first device using an equivalent private key KpriT to decrypt the information. The present invention is particularly applicable to a method of providing secure communication between a first and second decoder.
Inventors
- 👤 Christian Benardeau
- 👤 Jean-Luc Dauvois
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 08:09
CPC Classifications
H; H04; H04N; H04N21/00; H04N21/60; H04N21/63; H04N21/633; H04N21/6332; H04N21/6334; H04L; H04L63/00; H04L63/04; H04L63/0428; H04L63/0442; H04L63/06; H04L63/065; H04L63/08; H04L63/0823; H04L63/0853; H04L9/00; H04L9/40; H04N21/40; H04N21/41; H04N21/418; H04N21/4181; H04N21/43; H04N21/436; H04N21/4363; H04N21/43632; H04N21/4367; H04N21/45; H04N21/462; H04N21/4623; H04N7/00; H04N7/16; H04N7/167; H04N7/1675
Claims Analysis
Total Claims: 55
Claim 1
Independent Claim
78 words
A method of providing secure communication of information between at least a first and second digital audiovisual device and characterised in that the second device receives a certificate comprising a transport public key encrypted by a management private key, the second device decrypting the certificate using an equivalent management public key and thereafter using the transport public key to encrypt information sent to the first device, the first device using an equivalent private key to decrypt the information.
Claim 2
Independent Claim
78 words
A method of providing secure communication of information between at least a first and second digital audiovisual device and characterised in that the second device receives a certificate comprising a transport public key encrypted by a management private key, the second device decrypting the certificate using an equivalent management public key and thereafter using the transport public key to encrypt information sent to the first device, the first device using an equivalent private key to decrypt the information.
Claim 3
Dependent Claim
23 words
A method as claimed in claim 1 in which the transport private/public key pair are uniquely associated with the first and second device.
Claim 4
Dependent Claim
21 words
A method as claimed in claim 1 in which the encrypted information sent by the second device comprises a session key.
Claim 5
Dependent Claim
29 words
A method as claimed in claim 3 in which the session key is a key generated by the second device and usable in conjunction with a symmetric encryption algorithm.
Claim 6
Dependent Claim
29 words
A method as claimed in claim 3 in which the session key is used by the first device to encrypt control word information subsequently communicated to the second device.
Claim 7
Dependent Claim
36 words
A method as claimed in claim 5 in which the second device decrypts the control word information using the equivalent session key and thereafter descrambles the section of a scrambled transmission associated with this control word.
Claim 8
Dependent Claim
23 words
A method as claimed in claim 1 in which the first and second devices comprise a respective first and second portable security module.
Claim 9
Dependent Claim
56 words
A method as claimed in claim 1 in which the second device receives a system certificate comprising the management public key encrypted by a system private key, the second device decrypting the system certificate using a system public key so as to obtain the management public key used thereafter to decrypt the encrypted transport public key.
Claim 10
Dependent Claim
24 words
A method as claimed in claim 1 in which the communication link between the first and second devices is implemented by a bus connection.
Claim 11
Dependent Claim
22 words
A method as claimed in claim 1 in which the first and second digital audiovisual devices comprise a first and second decoder.
Claim 12
Dependent Claim
21 words
A method as claimed in claim 10 in which the first and second decoders are adapted to receive digital television transmissions.
Claim 13
Dependent Claim
24 words
A method as claimed in claim 1 in which the first and second digital audiovisual devices comprise a decoder device and a recorder device.
Claim 14
Independent Claim
84 words
A method of providing secure communication of information between a decoder device and a recorder device and characterised in that a first one of the devices communicates to the second device a certificate comprising a device public key encrypted by a management private key, the second device decrypting the certificate using an equivalent management public key and thereafter using the device public key to encrypt information sent to the first device, the first device using an equivalent device private key to decrypt the information.
Claim 15
Independent Claim
84 words
A method of providing secure communication of information between a decoder device and a recorder device and characterised in that a first one of the devices communicates to the second device a certificate comprising a device public key encrypted by a management private key, the second device decrypting the certificate using an equivalent management public key and thereafter using the device public key to encrypt information sent to the first device, the first device using an equivalent device private key to decrypt the information.
Claim 16
Dependent Claim
58 words
A method as claimed in claim 13 in which the first device communicates to the second device a system certificate comprising the management public key encrypted by a system private key, the second device decrypting the system certificate using a system public key so as to obtain the management public key used thereafter to decrypt the device certificate.
Claim 17
Dependent Claim
24 words
A method as claimed in claim 13 in which the device private/public key pair are uniquely associated with the identity of the first device.
Claim 18
Dependent Claim
24 words
A method as claimed in claim 13 in which the management private/public key pair are uniquely associated with the source of the first device.
Claim 19
Dependent Claim
24 words
A method as claimed in claim 14 in which the system private/public key pair are uniquely associated with the source of the second device.
Claim 20
Dependent Claim
21 words
A method as claimed in claim 13 in which the encrypted information sent by the second device comprises a session key.
Claim 21
Dependent Claim
29 words
A method as claimed in claim 18 in which the session key is a key generated by the second device and usable in conjunction with a symmetric encryption algorithm.
Claim 22
Dependent Claim
29 words
A method as claimed in claim 18 in which the session key is used by the decoder device to encrypt control word information subsequently communicated to the recorder device.
Claim 23
Dependent Claim
63 words
A method as claimed in claim 20 in which the recorder device may decrypt the control word information using the equivalent session key and thereafter re-encrypt the control word information using a recording encryption key, the re-encrypted control word information being stored by the recorder device on a recording support medium together with the scrambled transmission data associated with that control word information.
Claim 24
Dependent Claim
24 words
A method as claimed in claim 21 in which the recorder device communicates to the decoder device a copy of the recording encryption key.
Claim 25
Dependent Claim
26 words
A method as claimed in claim 22 in which the recorder device communicates a copy of the recording encryption key as encrypted by the session key.
Claim 26
Dependent Claim
26 words
A method as claimed in claim 13 in which at least one of the recorder device and decoder device comprises at least one portable security module.
Claim 27
Dependent Claim
25 words
A method as claimed in claim 13 in which the first device corresponds to a recorder device and the second device to a decoder device.
Claim 28
Dependent Claim
20 words
A method as claimed in claim 13 in which the decoder device is adapted to receive a digital television transmission.
Claim 29
Dependent Claim
29 words
A method as claimed in claim 3 in which the session key is a key generated by the second device and usable in conjunction with an asymmetric encryption algorithm.
Claim 30
Dependent Claim
27 words
A method as claimed in claim 3 in which the session key is used by the first device to encrypt data subsequently communicated to the second device.
Claim 31
Dependent Claim
22 words
A method as claimed in claim 28 which the session key is used by the second device to decrypt the encrypted data.
Claim 32
Dependent Claim
29 words
A method as claimed in claim 18 in which the session key is a key generated by the second device and usable in conjunction with an asymmetric encryption algorithm.
Claim 33
Dependent Claim
27 words
A method as claimed in claim 18 in which the session key is used by the decoder device to encrypt data subsequently communicated to the recorder device.
Claim 34
Dependent Claim
23 words
A method as claimed in claim 31 in which the session key is used by the recorder device to decrypt the encrypted data.
Claim 35
Dependent Claim
75 words
A combination comprising a first and a second digital audiovisual device, wherein the second device is adapted to receive a certificate comprising a transport public key encrypted by a management private key, to decrypt the certificate using an equivalent management public key and thereafter to use the transport public key to encrypt information to be sent to the first device, the first device being adapted to use an equivalent private key to decrypt the information.
Claim 36
Dependent Claim
75 words
A combination comprising a first and a second digital audiovisual device, wherein the second device is adapted to receive a certificate comprising a transport public key encrypted by a management private key, to decrypt the certificate using an equivalent management public key and thereafter to use the transport public key to encrypt information to be sent to the first device, the first device being adapted to use an equivalent private key to decrypt the information.
Claim 37
Dependent Claim
31 words
A combination as claimed in claim 33 wherein the second device is adapted to use the transport public key to encrypt a session key to be sent to the first device.
Claim 38
Dependent Claim
23 words
A combination as claimed in claim 34 in which the session key is a key usable in conjunction with a symmetric encryption algorithm.
Claim 39
Dependent Claim
23 words
A combination as claimed in claim 34 in which the session key is a key usable in conjunction with an asymmetric encryption algorithm.
Claim 40
Dependent Claim
30 words
A combination as claimed in claim 34 in which the first device is adapted to use the session key to encrypt data to be subsequently communicated to the second device.
Claim 41
Dependent Claim
24 words
A combination as claimed in claim 37 in which the second device is adapted to use the session key to decrypt the encrypted data.
Claim 42
Dependent Claim
20 words
A combination as claimed claim 33 , wherein one of said first and second devices is a portable security module.
Claim 43
Dependent Claim
85 words
A combination comprising a decoder device and a recorder device, wherein a first one of the devices is adapted to communicate to the second device a certificate comprising a device public key encrypted by a management private key, the second device being adapted to decrypt the certificate using an equivalent management public key and thereafter to use the device public key to encrypt information sent to the first device, the first device being adapted to use an equivalent device private key to decrypt the information.
Claim 44
Dependent Claim
85 words
A combination comprising a decoder device and a recorder device, wherein a first one of the devices is adapted to communicate to the second device a certificate comprising a device public key encrypted by a management private key, the second device being adapted to decrypt the certificate using an equivalent management public key and thereafter to use the device public key to encrypt information sent to the first device, the first device being adapted to use an equivalent device private key to decrypt the information.
Claim 45
Dependent Claim
31 words
A combination as claimed in claim 40 wherein the second device is adapted to use the device public key to encrypt a session key to be sent to the first device.
Claim 46
Dependent Claim
23 words
A combination as claimed in claim 41 in which the session key is a key usable in conjunction with a symmetric encryption algorithm.
Claim 47
Dependent Claim
23 words
A combination as claimed in claim 41 in which the session key is a key usable in conjunction with an asymmetric encryption algorithm.
Claim 48
Dependent Claim
30 words
A combination as claimed in claim 42 in which the first device is adapted to use the session key to encrypt data to be subsequently communicated to the second device.
Claim 49
Dependent Claim
23 words
A combination as claimed in claim 44 which the second device is adapted to use the session key to decrypt the encrypted data.
Claim 50
Dependent Claim
27 words
A method as claimed in claim 4 in which the session key is used by the first device to encrypt data subsequently communicated to the second device.
Claim 51
Dependent Claim
27 words
A method as claimed in claim 27 in which the session key is used by the first device to encrypt data subsequently communicated to the second device.
Claim 52
Dependent Claim
27 words
A method as claimed in claim 19 in which the session key is used by the decoder device to encrypt data subsequently communicated to the recorder device.
Claim 53
Dependent Claim
27 words
A method as claimed in claim 30 in which the session key is used by the decoder device to encrypt data subsequently communicated to the recorder device.
Claim 54
Dependent Claim
30 words
A combination as claimed in claim 43 in which the first device is adapted to use the session key to encrypt data to be subsequently communicated to the second device.
Claim 55
Dependent Claim
24 words
A combination as claimed in claim 50 in which the second device is adapted to use the session key to decrypt the encrypted data.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2008-06-06 | 2008-12-06 | 2009-06-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2012-06-06 | 2012-12-06 | 2013-06-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2016-06-06 | 2016-12-06 | 2017-06-07 | $7700.00 | Window Closed / Lapsed |