Cryptography – Cryptanalysis
Patent
1996-10-29
1999-11-23
Cangialosi, Salvatore
Cryptography
Cryptanalysis
H04L 900
Patent
active
059914009
ABSTRACT:
In a conditional access system, transmitted information is recorded in a scrambled form SV. Accordingly, any access to the recorded information SV is subject to the condition that proper control word(s) CW are available. To enable access to the recorded information SV, control word regeneration data ECM, KRD is stored. The proper control word(s) CW cannot easily be derived from this control word regeneration data ECM, KRD. However security device SCD is capable of retrieving the proper control word(s) CW from the control word regeneration data ECM, KRD. A system operator effectively masters operations carried out in the security device SCD. Accordingly, if the system operator so desires, he may inhibit retrieval of the control word(s) CW and, consequently, prevent access to the recorded information SV. The conditional access system may be used in, for example, pay-TV or multimedia purposes.
REFERENCES:
patent: 4485468 (1984-11-01), Slana
patent: 4727579 (1988-02-01), Wright et al.
patent: 4817143 (1989-03-01), Murray
patent: 4937866 (1990-06-01), Crowther et al.
patent: 5224161 (1993-06-01), Daniel et al.
patent: 5243650 (1993-09-01), Roth et al.
patent: 5249229 (1993-09-01), Poivet et al.
patent: 5530756 (1996-06-01), Bourel et al.
patent: 5588058 (1996-12-01), Le Berre
patent: 5689559 (1997-11-01), Park
"Encipherment and Conditional Access" by L.C. Guillou and J.L. Giachetti, published in the SMPTE Journal of Jun. 1994.
Belk Michael E.
Cangialosi Salvatore
U.S. Philips Corporation
LandOfFree
Time-shifted conditional access does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Time-shifted conditional access, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Time-shifted conditional access will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1231160