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1. (WO1997016924) TIME-SHIFTED CONDITIONAL ACCESS
Latest bibliographic data on file with the International Bureau

Pub. No.: WO/1997/016924 International Application No.: PCT/IB1996/001137
Publication Date: 09.05.1997 International Filing Date: 23.10.1996
IPC:
H04N 5/765 (2006.01) ,H04H 20/76 (2008.01) ,H04K 1/04 (2006.01) ,H04L 9/00 (2006.01) ,H04N 5/92 (2006.01) ,H04N 7/167 (2011.01)
H ELECTRICITY
04
ELECTRIC COMMUNICATION TECHNIQUE
N
PICTORIAL COMMUNICATION, e.g. TELEVISION
5
Details of television systems
76
Television signal recording
765
Interface circuits between an apparatus for recording and another apparatus
H ELECTRICITY
04
ELECTRIC COMMUNICATION TECHNIQUE
H
BROADCAST COMMUNICATION
20
Arrangements for broadcast or for distribution combined with broadcast
65
Arrangements characterised by transmission systems for broadcast
76
Wired systems
H ELECTRICITY
04
ELECTRIC COMMUNICATION TECHNIQUE
K
SECRET COMMUNICATION; JAMMING OF COMMUNICATION
1
Secret communication
04
by frequency scrambling, i.e. by transposing or inverting parts of the frequency band or by inverting the whole band
H ELECTRICITY
04
ELECTRIC COMMUNICATION TECHNIQUE
L
TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
9
Arrangements for secret or secure communication
H ELECTRICITY
04
ELECTRIC COMMUNICATION TECHNIQUE
N
PICTORIAL COMMUNICATION, e.g. TELEVISION
5
Details of television systems
76
Television signal recording
91
Television signal processing therefor
92
Transformation of the television signal for recording, e.g. modulation, frequency changing; Inverse transformation for playback
H ELECTRICITY
04
ELECTRIC COMMUNICATION TECHNIQUE
N
PICTORIAL COMMUNICATION, e.g. TELEVISION
7
Television systems
16
Analogue secrecy systems; Analogue subscription systems
167
Systems rendering the television signal unintelligible and subsequently intelligible
Applicants:
PHILIPS ELECTRONICS N.V. [NL/NL]; Groenewoudseweg 1 NL-5621 BA Eindhoven, NL
PHILIPS NORDEN AB [SE/SE]; Kottbygatan 7 Kista S-164 85 Stockholm, SE (SE)
Inventors:
KAMPERMAN, Franciscus, Lucas, Antonius, Johannes; NL
Agent:
KOOIMAN, Josephus, J., A.; Internationaal Octrooibureau B.V. P.O. Box 220 NL-5600 AE Eindhoven, NL
Priority Data:
95202980.931.10.1995EP
Title (EN) TIME-SHIFTED CONDITIONAL ACCESS
(FR) ACCES CONDITIONNEL A DECALAGE TEMPOREL
Abstract:
(EN) 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.
(FR) Dans un système d'accès conditionnel, l'information transmise est enregistrée sous une forme (SV) brouillée. De ce fait, tout accès à l'information (SV) enregistrée est conditionné par le fait qu'un ou plusieurs mot(s) de commande (CW) approprié(s) soient disponibles. Afin d'autoriser l'accès à l'information enregistrée (SV), des messages de contrôle d'admissibilité (ECM) de données de régénération de mot de commande (KRD) sont mémorisées. Le ou les mots de commande (CW) peuvent difficilement être dérivés de ces messages de contrôle d'admissibilité (ECM) de données de régénération de mot de commande (KRD). Un dispositif de sécurité (SCD) est, toutefois, en mesure d'extraire le ou les mots de commande (CW) appropriés des messages de contrôle d'admissibilité (ECM) de données de régénération de mot de commande (KRD). Un opérateur de système régit efficacement les opérations exécutées dans le dispositif de sécurité (SCD). De ce fait, si cet opérateur de système le souhaite, il peut arrêter l'extraction du ou des mots de commande (CW) et, partant, interdire l'accès à l'information enregistrée (SV). Il est possible, par exemple, de mettre en oeuvre ce système d'accès conditionnel dans une télévision à péage ou dans des multimédias.
Designated States: JP, KR
European Patent Office (AT, BE, CH, DE, DK, ES, FI, FR, GB, GR, IE, IT, LU, MC, NL, PT, SE)
Publication Language: English (EN)
Filing Language: English (EN)
Also published as:
ES2206594EP0800745US5991400JP4491069 JPH10512428 DE000069630012
KR1019987001184MYPI 96004526