USRE33189E - Security system for SSTV encryption - Google Patents

Security system for SSTV encryption Download PDF

Info

Publication number
USRE33189E
USRE33189E US07/409,955 US40995589A USRE33189E US RE33189 E USRE33189 E US RE33189E US 40995589 A US40995589 A US 40995589A US RE33189 E USRE33189 E US RE33189E
Authority
US
United States
Prior art keywords
signal
sequence
key number
means
receiver
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US07/409,955
Inventor
Lin-nan Lee
Russell J. Fang
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Comsat Corp
Original Assignee
Comsat Corp
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority to US06/322,833 priority Critical patent/US4484027A/en
Application filed by Comsat Corp filed Critical Comsat Corp
Priority to US07/409,955 priority patent/USRE33189E/en
Application granted granted Critical
Publication of USRE33189E publication Critical patent/USRE33189E/en
Assigned to COMSAT CORPORATION reassignment COMSAT CORPORATION CHANGE OF NAME (SEE DOCUMENT FOR DETAILS). Assignors: COMMUNICATIONS SATELLITE CORPORATION
Anticipated expiration legal-status Critical
Application status is Expired - Lifetime legal-status Critical

Links

Images

Classifications

    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04NPICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N7/00Television systems
    • H04N7/16Analogue secrecy systems; Analogue subscription systems
    • H04N7/167Systems rendering the television signal unintelligible and subsequently intelligible
    • H04N7/1675Providing digital key or authorisation information for generation or regeneration of the scrambling sequence

Abstract

In a secure communications system, a key number which is changed periodically, e.g. monthly, and a random number from a random number generator are combined and used as a seed to reset a PN sequence generator, with the output of the generator being used to control encryption of transmission data in a signal processor. The key is also provided to a first encipherer to encipher the random number for transmission with the encrypted data. At the receiver, the key is provided on common to a decipherer for deciphering the random number and a PN sequence generator which is periodically reset by the combination of the key and random number in the same manner as in the transmitter. The PN sequence is then used to decrypt the information. User identification codes are stored in the transmitter and are used to encipher the key, with each employing its ID code to decipher the key. The user ID codes are known only to the system operator, so that not even a particular user can know the key.

Description

.Iadd.This is a continuation of application No. 07/192,014 filed May 9, 1988, now abandoned seeking Reissue of U.S. Pat. No. 4,484,027. .Iaddend.

BACKGROUND OF THE INVENTION

The present invention is related to the confidentiality of television signal transmissions, and more particularly to the protection of TV signal transmissions from unauthorized reception. The environment in which the present invention may be widely applicable, and in the context of which the invention will be described herein, is that of subscriber television and TV program distribution.

Subscriber television systems are becoming increasingly widespread wherein TV signals are sent out via a cable network or over the air and are intended for reception and viewing by only those subscribers who have paid a monthly fee. With the increase in subscriber television systems has also come an increase in the number of people attempting to receive and display the premium television programs without payment. Thus, there is a need for more sophisticated security techniques for preventing such unauthorized reception.

Many existing subscriber television systems utilize, directly or indirectly, signals transmitted via satellite, and it is becoming quite common for non-paying individuals to receive and display the premium television programs via television receive only (TVRO) antennas, thus resulting in a substantial loss of revenue for the distributors of the subscription television programs. In addition, various direct satellite broadcast television systems are currently being proposed wherein subscription television programs will be broadcast directly via satellite to individual subscriber homes. These subscription satellite television (SSTV) systems will be quite vulnerable to unauthorized reception, and an effective security technique is therefore highly desirable.

The purpose of a security subsystem for an SSTV system is to protect the distributor's business interest and, accordingly, the following objectives should be achieved:

(1) To prevent a non-subscriber from receiving intelligible video and audio signals by using a regular home television set;

(2) To prevent a delinquent subscriber from receiving intelligible video and audio signals by using the SSTV decoder;

(3) To prevent a legitimate subscriber from receiving intelligible video and audio signals of unsubscribed SSTV channels or programs;

(4) To discourage an average technician from building his own receiver capable of obtaining acceptable quality video and audio signals;

(5) To discourage a small unauthorized business concern from manufacturing and marketing devices which are capable of receiving and displaying acceptable quality video and audio signals from the SSTV channels; and

(6) To allow a legitimate subscriber to receive and display high quality video and audio signals from the subscribed channels or programs.

It would also be highly desirable to achieve the above objectives at a reasonable cost.

A number of security systems for CATV exist, most of which involve the suppression or removal of the horizontal sync pulses from the video signal before transmission, and the recovery of the sync pulses at the receive end. These techniques will prevent people without the sync recovery circuits from receiving and displaying the programs and may therefore achieve objectives (1) and (6) above, but .[.those.]. .Iadd.these .Iaddend.security systems do not achieve objectives (2) and (3) and, since sync recovery circuits are relatively easily designed and manufactured, also do not satisfy objectives (4) and (5).

More sophisticated techniques may include additional intelligence in the subscriber's decoder box, including the capability of receiving commands from a control center which are specifically addressed to an individual subscriber and are used to turn on or off some or all of the channels. These more sophisticated security techniques may succeed in achieving objectives (1)-(3) and (6), but still do not satisfy objectives (4) and (5). For example, most of these techniques involve the checking of a password, and a particular channel is turned on only if the password is matched. This could be relatively easily by-passed by modifying the subscriber's decoder box or building a separate box with all of the necessary features except the on/off switch. Further, subscribers may also be able to tamper with the decoder box to receive more programs than are actually paid for.

SUMMARY OF THE INVENTION

It is an object of the present invention to provide a security subsystem for a subscription television system wherein all of the above-mentioned objectives (1)-(6) are achieved.

It is a further object of this invention to provide such a security subsystem of minimal cost and complexity.

These and other objects are achieved according to the present invention by using a cryptographic technique for scrambling and descrambling of the video signals. The scrambling and descrambling techniques utilize a "key" which is changed on a regular basis and is sent only to paid subscribers, and even this "key" is sent in a different encrypted form to each subscriber so that delinquent subscribers cannot learn the current key from others.

A record is kept of unique user ID codes corresponding to each subscriber, and in a transmitter according to the preferred embodiment of this invention, the key is ciphered with each subscriber's unique ID code prior to sending the key to that subscriber. A random number generator in the transmitter generates a new random number at regular intervals, for example, every second, and this number is combined with the key, and the combined number is then used as a seed to reset a PN sequence generator every second. This PN sequence generator will thus generate a PN sequence with a random seed in one-second segments, and the segmented PN sequence is supplied to a signal processor where it is used to scramble the audio and video program signals. The random number generator is also ciphered with the key and the enciphered random number is continually transmitted with the scrambled video signal.

At the receiver, the enciphered key, which has been sent either via satellite or mail, is deciphered in the receiver utilizing the particular subscriber's unique ID code, which ID code is internal to the receiver and is unknown to the subscriber. The deciphered key is then in turn used to decipher the enciphered random number received with the scrambled program signal. The deciphered key and random number are then combined as in the transmitter, and the combined signal is used to continually reset a PN sequence generator identical to that in the transmitter so that a segmented PN sequence will be generated in the reciver which is identical to that generated in the transmitter, and this segmented PN sequence can then be used to descramble the received signal. The descrambled signal will then be supplied to the subscriber television set.

BRIEF DESCRIPTION OF THE DRAWING

The invention will be more clearly understood with reference to the following description in conjunction with the accompanying drawing wherein the single FIGURE is a block diagram of the essential components of the SSTV security system according to the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

The drawing illustrates a functional block diagram of the SSTV security system according to this invention. The SSTV transmitter will typically include or have access to a billing system computer 10 which will store subscriber information including a list of paid subscribers and their corresponding unique user ID codes. This information may typically be stored in a user data base 12 within the computer. Also within the computer will be a register 14 or the like containing a key which will be changed on a regular basis, e.g. monthly. In preparation for sending this "key of the month" to each current subscriber, the key is enciphered in an encipherer 16 with the user ID code unique to that particular current subscriber, and the enciphered key is then sent to the subscriber.

The transmitter includes a pseudo-random number (PN) sequence generator 18 and a random number generator 20. The random number generator 20 periodically generates a new random number, e.g. once every second, and the outputs of the random number generator 20 and key register 14 are combined and loaded into the PN sequence generator 18 to periodically reset or "seed" the PN sequence generator 18 in a manner well known in the art. Each seeding of the sequence generator 18 will begin a new segment of the PN sequence. The program signal from source 22 is supplied to a signal processor 24 where it is encrypted with the segmented PN sequence from generator 18. The encryption technique used may be any one of a variety of well known techniques and need not be discussed in detail herein. The encrypted, or scrambled, signal is then provided to a transmitter 26 for transmission over link 100 to the various subscriber receivers.

The random number from generator 20 is enciphered with the key of the month in an encipherer 28, and the enciphered random number is transmitted with the scrambled video signal over the link 100.

At the receiver, a register 30 or the like internal to the subscriber TV receiver contains a subscriber-specific secret user ID code which is set prior to installation and is stored in the user data base 12 of the billing computer at the transmitter. Thus, when the subscriber receiver receives the enciphered key or when the user receives the enciphered key by mail and enters the enciphered key into the receiver, a decipherer 32 in the receiver deciphers the enciphered key with the secret user ID code specific to that particular subscriber, and the deciphered key is provided to a decipherer 34. A receiver 36 separates the scrambled signal from the enciphered random number received over link 100 and provides the enciphered random number to the decipherer 34 where it is deciphered with the key received from the decipherer 32. The deciphered random number and key are then combined and loaded into the PN sequence generator 38 to reset or "seed" the sequence generator in the same manner as in the transmitter, to thereby result in the same segmented PN sequence as was used for scrambling in the SSTV transmitter signal processor 24. This segmented PN sequence is then provided to signal processor 40 where it is used to descramble the received program signal. The descrambled signal is then provided to the subscriber television set 42.

The above-described security system provides a novel technique for generating and synchronizing a segmented pseudo-random number (PN) sequence, and a secure key distribution method. The segmented PN sequence generated is used to control the video and audio signal processors that scramble and descramble the program signals. Since a different segmented PN sequence will be generated by each distinct key, the scrambling sequence is different for each key, and by periodically changing the key the scrambling and descrambling sequences will change. Thus, it is not possible for anyone without exact knowledge of the current key to descramble the received program signal with or without a descrambling device.

For each given duration of time, a particular channel is scrambled by a PN sequence that is generated by a randomly selected number and the key of the month. To prevent subscribers of different channels from exchanging the keys among themselves, it is essential that the key for a given channel distributed to each subscriber look different, and this accomplished by enciphering the key with each subscriber's unique user ID code. In this way, although a single key is provided by the register 14 at any one time, a different key is required by each subscriber. It is only when the subscriber-specific key is entered into the receiver that the true key of the month contained in register 14 can be provided to the decipherer 34 and sequence generator 38, and the deciphering of this true key of the month in the decipherer 32 is performed internally of the subscriber receiver and without the subscriber's knowledge.

An important feature of any security system is that a legitimate subscriber must be capable of obtaining synchronization within a short period of time. In the system according to the present invention, the PN sequence used for scrambling and descrambling the signal in signal processors 24 and 40, respectively, is separated into short segments each of which is seeded by the combination of the key of the month and a random number which changes, for example, once every second. Thus, assuming that a legitimate subscriber does have his appropriate key, the time required to acquire synchronization will be substantially equal to the duration of each random number so that synchronization can be acquired rapidly in case of loss of sync due to power outages, rainstorms, changing of channels, etc.

The individual components in the security system according to the present invention are known in the art and need not be described in detail herein since the internal details of these components do not constitute a part of the present invention. The encipherers used to encipher the key of the month and the random number can be two different encipherers, but for the sake of hardware simplicity at the receive side, and consequent cost savings in mass production of the subscriber receivers, it is preferable that the same encipherers be used. The encipherer may employ any enciphering method as long as it has a sufficiently high level of security.

The PN sequence generator can be any general PN sequence generator as long as it also has sufficient security strength, e.g. a properly selected non-linear feedback shift register may suffice.

The random number generator in the transmitter may be a well known thermal noise generator which generates "true" random numbers, or it may be a pseudo-random number generator similar to the sequence generator 18, implemented in a well known manner with digital electronics or computer software. Similarly, the technique for combining the key of the month and the random number generator to produce the "seed" for the PN sequence generators 18 and 38 is not critical, with the simplest technique being a bit-by-bit modulo-2 addition of the two numbers.

In general, each of the functional blocks in the drawing can be implemented with existing techniques, with system complexity and cost and security strength depending on the particular implementation of each of the functional blocks.

The transformation of the simple cipherer is specified by a variable which is different for each channel or special program, and is changed every month.

The user ID code 30 within each subscriber set may be a set of binary switches or a bit pattern programmed into a read-only memory in a sealed box to prevent the subscriber from seeing or changing the number.

The use of a simple cipherer in addition to the non-linear feedback shift-register may seem to increase the system complexity unnecessarily. However, since only a small amount of data, namely the "seed", need be handled each time, and since the statistical properties of the cipherer do not impact to the output of the PN sequence generator, the cipherer can be very simple. One possible approach, for example, is a ROM table of random bits with or without cipher feedback. The use of this simple cipherer greatly simplifies the problem of cryptosynchronization and key distribution, and therefore reduces the overall system complexity.

Suitable alternatives for the scrambling of the program signals include conventional scrambling techniques such as on-off switching, randomly inverting lines, fields or frames, and delaying horizontal lines or fields by certain randomly fixed steps. In any case, the technique used will require the generation of a PN sequence which must be synchronized at both the transmit and receive sides.

Claims (28)

What is claimed is:
1. In a communications system including a transmitter and a receiver, said transmitter including a program source for providing a program signal representing program information, a transmit signal processor for encrypting said program signal in accordance with a transmit control signal and transmit means for transmitting said encrypted signal, said receiver including receive means for receiving said encrypted signal, a receiver signal processor for decrypting said encrypted signal in accordance with a receive control signal and means for receiving said decrypted signal and providing said program information, the improvement comprising:
first generator means at said transmitter for generating a first sequence of signals representing a first sequence of numbers;
key number means at said transmitter for providing a key number signal representing a key number;
second generator means at said transmitter for generating a second sequence of signals representing a second sequence of numbers, said second generator means being periodically reset by a reset signal comprising the output of said first generator means to thereby generate a plurality of sequence segments each beginning with a reset signal, the output of said second generator means comprising said transmit control signal;
means at said transmitter for enciphering said first sequence of signals with said key number signal and for providing said enciphered first signal sequence to said transmit means for transmission with said encrypted program signal;
.Iadd.means at said transmitter for enciphering said key number signal in accordance with a further signal; .Iaddend.
means at said receiver for providing said key number signal.Iadd., said means at said receiver for providing said key number signal comprising means at said receiver for providing said further signal and means at said receiver for deciphering said enciphered key number signal in accordance with said further signal.Iaddend.;
receive deciphering means at said receiver for receiving said enciphered first signal sequence and said key number, deciphering said first signal sequence in accordance with said key number and providing said deciphered first signal sequence as an output; and
receive generating means for generating a sequence of signals representing said first sequence of numbers, said receive generating means being periodically reset by a reset signal comprising the output of said receive deciphering means to thereby generate said plurality of sequence segments, said plurality of sequence segments being provided by said receive generating means to said receive signal processor as said receive control signal.
2. A communications system as defined in claim 1, .[.further comprising:
means for providing.]. .Iadd.wherein said further signal comprises .Iaddend.an identification number signal uniquely identifying said receiver.[.;
means for enciphering said key number signal with said identification signal;
means at said receiver for providing said identification number signal; and
means at said receiver for receiving said identification number signal and said enciphered key number signal and for deciphering said key number signal, said deciphered key number signal being provided to said receive deciphering means.]..
3. A communications system as defined in .[.either one of claims 1 or 2.]. .Iadd.claim 1.Iaddend., wherein each of said reset signals provided to said second generator means comprises a combination of said key number signal and a signal of said first signal sequence, and wherein each of said reset signals provided to said receive generator means comprises a combination of said key number signal and a signal of said deciphered first signal sequence.
4. A communications systems as defined in claim 3, wherein said key number signal is changed at predetermined time intervals.
5. A communications system as defined in claim 4, wherein said second generator means is a non-linear pseudorandom sequence generator.
6. A communications system as defined in claim 3, wherein a plurality of receivers receive the encrypted signal transmitted by said transmitter, each of said receivers having a corresponding unique identification number and said enciphered key number received at each receiver being enciphered with the user identification number unique to said each receiver.
7. The communications system as defined in claim 6, wherein said first signal sequence represents a substantially random number sequence.
8. In a method of providing security in a signal transmission system, said method including the steps of encrypting in accordance with an encryption control signal a progam signal representing information, transmitting said encrypted signal, receiving said encrypted signal, decrypting said received encrypted signal in accordance with a decryption control signal and providing said information represented by said decrypted signal, the improvement comprising:
generating a key number signal representing a key number;
generating a first signal sequence representing a first sequence of numbers;
generating a second signal sequence representing a second sequence of numbers, said second signal sequence being periodically reset by a reset signal comprising a signal of said first signal sequence to thereby generate a plurality of second sequence segments;
providing said second sequence segments to said transmit signal processor as said encryption control signal;
enciphering said first signal sequence with said key number and providing said enciphered first sequence to said transmitter for transmission with said encrypted signal;
.Iadd.enciphering said key number signal in accordance with a further signal;
deciphering said enciphered key number signal in accordance with said further signal at said receiver; .Iaddend.
decrypting said enciphered first sequence at said receiver in accordance with said key number signal;
generating said second sequence segments at said receiver by resetting a receive number signal generator with a reset signal comprising said deciphered first signal sequence; and
providing said second sequence segments to said receive signal processor as said decryption control signal.
9. A method as defined in claim 8, further .[.comprising:
enciphering said key number signal at said transmitter with.]. .Iadd.wherein said further signal comprises .Iaddend.a user identification number signal uniquely identifying said receiver.[.;
transmitting said enciphered key number signal to said receiver;
deciphering said enciphered key number signal at said receiver in accordance with said user identification number signal uniquely identifying said receiver; and
providing said deciphered key number signal to said deciphering means.]..
10. The method as defined in claim 9, further comprising the steps of:
combining said key number signal and a signal in said first sequence to obtain said reset signal in said transmitter; and
combining said key number signal and a signal in said deciphered first sequence in order to obtain said reset signal in said receiver.
11. The method as defined in any one of claims 8-10, further comprising the step of periodically changing said key number signal.
12. The method as defined in claim 11, wherein said second generator means in said transmitter and said generator means in said receiver each generate non-linear pseudo-random signal sequences.
13. The method as defined in claim 12, wherein said first signal sequence represents a substantially random number sequence.
14. A communications system including a transmitter and a receiver, said system comprising:
a program source at said transmitter for providing a program signal representing program information;
first generator means at said transmitter for generating a first sequence of signals representing a first sequence of numbers;
key number means at said transmitter for providing a key number signal representing a key number;
transmit signal processing means at said transmitter responsive to at least said first sequence of signals for encrypting said program signal;
enciphering means at said transmitter for enciphering said first sequence of signals with said key number signal to provide an enciphered first signal sequence;
transmit means at said transmitter for transmitting said encrypted program signal and said enciphered first signal sequence;
.Iadd.means at said transmitter for enciphering said key number signal in accordance with a further signal; .Iaddend.
means at said receiver for providing said key number signal.Iadd., said means at said receiver for providing said key number signal comprising means at said receiver for providing said further signal and means at said receiver for deciphering said enciphered key number signal in accordance with said further signal.Iaddend.;
receiver deciphering means at said receiver for receiving said enciphered first signal sequence and said key number, deciphering said first signal sequence in accordance with said key number and providing said deciphered first signal sequence as an output; and
receive generating means at said receiver responsive to at least said output of said receive deciphering means for receiving and decrypting said encrypted program signal to obtain said program signal.
15. A communications system as defined in claim 14, wherein said transmit signal processing means includes encryption means for encrypting said program signal in accordance with an encryption control signal, and second generator means at said transmitter for generating a second sequence of signals representing a second sequence of numbers, said second generator means being periodically reset by a reset signal comprising at least the output of said first generator means to thereby generate a plurality of sequence segments each beginning with a reset signal, the output of said second generator means comprising said encryption control signal.
16. A communications system as defined in claim 15, wherein said reset signal comprises a combination of said key number signal and the output of said first generator means.
17. A method of providing security in a signal transmission system between a transmitter and a receiver, said method comprising the steps of:
providing a program signal representing information;
generating a first sequence of signals representing a first sequence of numbers;
providing a key number signal representing a key number;
encrypting said program signal in accordance with at least said first sequence of signals;
enciphering said first sequence of signals with said key number signal to provide an enciphered first signal sequence;
transmitting said encrypted program signal and said enciphered first signal sequence to said receiver;
.Iadd.enciphering said key number signal in accordance with a further signal; .Iaddend.
providing said key number signal at said receiver .Iadd.by deciphering said enciphered key number signal in accordance with said further signal.Iaddend.;
deciphering said first signal sequence at said receiver in accordance with said key number to obtain a deciphered first signal sequence; and
decrypting said encrypted program signal at said receiver in accordance with at least deciphered first signal sequence to obtain said program signal.
18. A method as defined in claim 17, wherein said step of encrypting said program signal in accordance with at least said first sequence of signals comprises the steps generating a second sequence of signals representing a second sequence of numbers, said second sequence of signals comprising a plurality of sequence segments each beginning with a reset signal, said reset signal comprising at least said first signal sequence, .[.said.]. .Iadd.and .Iaddend.encrypting said program signal in accordance with said second sequence of signals.
19. A method as defined in claim 18, wherein said reset signal comprises a combination of said key number signal and said first sequence of signals. .Iadd.20. In a communications system including a transmitter and a receiver, said transmitter including a program source for providing a program signal representing program information, a transmit signal processor for encrypting said program signal in accordance with a transmit control signal and transmit means for transmitting said encrypted signal, said receiver including receive means for receiving said encrypted signal, a receiver signal processor for decrypting said encrypted signal in accordance with a receive control signal and means for receiving said decrypted signal and providing said program information, the improvement comprising:
first generator means at said transmitter for generating a first sequence of signals representing a first sequence of numbers;
key number means at said transmitter for providing a key number signal representing a key number;
second generator means at said transmitter for generating a second sequence of signals representing a second sequence of numbers, said second generator means being periodically reset by a reset signal comprising the output of said first generator means to thereby generate a plurality of sequence segments each beginning with a reset signal, the output of said second generator means comprising said transmit control signal;
means at said transmitter for enciphering said first sequence of signals with said key number signal and for providing said enciphered first signal sequence to said transmit means for transmission with said encrypted program signal;
means at said receiver for providing said key number signal;
receive deciphering means at said receiver for receiving said enciphered first signal sequence and said key number, deciphering said first signal sequence in accordance with said key number and providing said deciphered first signal sequence as an output; and
receive generating means for generating a sequence of signals representing said first sequence of numbers, said receive generating means being periodically reset by a reset signal comprising the output of said receive deciphering means to thereby generate said plurality of sequence segments, said plurality of sequence segments being provided by said receive generating means to said receive signal processor as said receive control signal;
said communications system further comprising:
means for providing an identification number signal uniquely identifying said receiver;
means for enciphering said key number signal with said identification number signal;
means at said receiver for providing said identification number signal; and
means at said receiver for receiving said identification number signal and said enciphered key number signal and for deciphering said key number signal, said deciphered key number signal being provided to said receive
deciphering means. .Iaddend. .Iadd.21. A communications system as defined in claim 20, wherein each of said reset signals provided to said second generator means comprises a combination of said key number signal and a signal of said first signal sequence, and wherein each of said reset signals provided to said receive generator means comprises a combination of said key number signal and a signal of said deciphered first signal sequence. .Iaddend. .Iadd.22. A communications system as defined in claim 21, wherein said key number signal is changed at predetermined time intervals. .Iaddend. .Iadd.23. A communications system as defined in claim 22, wherein said second generator means is a non-linear pseudorandom sequence generator. .Iaddend. .Iadd.24. A communications system as defined in claim 21, wherein a plurality of receivers receive the encrypted signal transmitted by said transmitter, each of said receivers having a corresponding unique identification number and said enciphered key number received at each receiver being enciphered with the user identification number unique to said each receiver. .Iaddend. .Iadd.25. A communications system as defined in claim 24, wherein said first signal sequence represents a substantially random number sequence. .Iaddend. .Iadd.26. In a method of providing security in a signal transmission system, said method including the steps of encrypting in accordance with an encryption control signal a program signal representing information, transmitting said encrypted signal, receiving said encrypted signal, decrypting said received encrypted signal in accordance with a decryption control signal and providing said information represented by said decrypted signal, the improvement comprising:
generating a key number signal representing a key number;
generating a first signal sequence representing a first sequence of numbers;
generating a second signal sequence representing a second sequence of numbers, said second signal sequence being periodically reset by a reset signal comprising a signal of said first signal sequence to thereby generate a plurality of second sequence segments;
providing said second sequence segments to said transmit signal processor as said encryption control signal;
enciphering said first signal sequence with said key number and providing said enciphered first sequence to said transmitter for transmission with said encrypted signal;
decrypting said said enciphered first sequence at said receiver in accordance with said key number signal;
generating said second sequence segments at said receiver by resetting a receive number signal generator with a reset signal comprising said deciphered first signal sequence;
providing said second sequence segments to said receive signal processor as said decryption control signal;
said method further comprising:
enciphering said key number signal at said transmitter with a user identification signal uniquely identifying said receiver;
transmitting said enciphered key number signal to said receiver;
deciphering said enciphered key number signal at said receiver in accordance with said user identification number signal uniquely identifying said receiver; and
providing said deciphered key number signal to said deciphering means.
.Iaddend. .Iadd.27. The method as defined in claim 26, further comprising the steps of:
combining said key number signal and a signal in said first sequence to obtain said reset signal in said transmitter; and
combining said key number signal and a signal in said deciphered first sequence in order to obtain said reset signal in said receiver. .Iaddend.
.Iadd.28. The method as defined in any one of claims 26 or 27, further comprising the step of periodically changing said key number signal. .Iaddend. .Iadd.29. The method as defined in claim 28, wherein said second generator means in said transmitter and said generator means in said receiver each generate non-linear pseudo-random signal sequences. .Iaddend. .Iadd.30. The method as defined in claim 29, wherein said first signal sequence represents a substantially random number sequence. .Iaddend. .Iadd.31. A communications system including a transmitter and a receiver, said system comprising:
a program source at said transmitter for providing a program signal representing program information;
first generator means at said transmitter for generating a first sequence of signals representing a first sequence of numbers;
key number means at said transmitter for providing a key number signal representing a key number;
transmit signal processing means at said transmitter responsive to at least said first sequence of signals for encrypting said program signal;
enciphering means at said transmitter for enciphering said first sequence of signals with said key number signal to provide an enciphered first signal sequence;
transmit means at said transmitter for transmitting said encrypted program signal and said enciphered first signal sequence;
means at said receiver for providing said key number signal;
receive deciphering means at said receiver for receiving said enciphered first signal sequence and said key number, deciphering said first signal sequence in accordance with said key number and providing said deciphered first signal sequence as an output; and
receive generating means at said receiver responsive to at least said output of said receive deciphering means for receiving and decrypting said encrypted program signal to obtain said program signal;
wherein said transmit signal processing means includes encryption means for encrypting said program signal in accordance with an encryption control signal, and second generator means at said transmitter for generating a second sequence of signals representing a second sequence of numbers, said second generator means being periodically reset by a reset signal comprising at least the output of said first generator means to thereby generate a plurality of sequence segments each beginning with a reset signal, the output of said second generator means comprising said encryption control signal; and
wherein said reset signal comprises a combination of said key number signal
and the output of said first generator means. .Iaddend. .Iadd.32. A method of providing security in a signal transmission system between a transmitter and a receiver, said method comprising the steps of:
providing a program signal representing information;
generating a first sequence of signals representing a first sequence of numbers;
providing a key number signal representing a key number;
encrypting said program signal in accordance with at least said first sequence of signals;
enciphering said first sequence of signals with said key number signal to provide an enciphered first signal sequence;
transmitting said encrypted program signal and said enciphered first signal sequence to said receiver;
providing said key number signal at said receiver;
deciphering said first signal sequence at said receiver in accordance with said key number to obtain a deciphered first signal sequence; and
decrypting said encrypted program signal at said receiver in accordance with at least said deciphered first signal sequence to obtain said program signal;
wherein said step of encrypting said program signal in accordance with at least said first sequence of signals comprises the steps of generating a second sequence of signals representing a second sequence of numbers, said second sequence of signals comprising a plurality of sequence segments each beginning with a reset signal, said reset signal comprising at least said first signal sequence, and encrypting said program signal in accordance with said second sequence of signals; and
wherein said reset signal comprises a combination of said key number signal
and said first sequence of signals. .Iaddend. .Iadd.33. A communications system as defined in claim 1, wherein said further signal is fixed during normal operation of said system. .Iaddend. .Iadd.34. A communications system as defined in claim 1, wherein said key number signal is periodically changed. .Iaddend. .Iadd.35. A communications system as defined in claim 34, wherein said key number signal changes at a rate slower than the signals of said first sequence of signals. .Iaddend. .Iadd.36. A method as defined in claim 8, wherein said further signal is fixed during normal operation of said system. .Iaddend. .Iadd.37. A method as defined in claim 8, wherein said step of generating said key number signal comprises periodically changing said key number signal. .Iaddend.
.Iadd.38. A method as defined in claim 37, wherein said key number signal is changed at a rate slower than the signals of said first sequence of signals. .Iaddend. .Iadd.39. A communications system as defined in claim 14, wherein said further signal is fixed during normal operation of said system. .Iaddend. .Iadd.40. A communications system as defined in claim 14, wherein said key number signal is periodically changed. .Iaddend. .Iadd.41. A communications system as defined in claim 40, wherein said key number signal changes at a rate slower than the signals of said first sequence of signals. .Iaddend. .Iadd.42. A method as defined in claim 17, wherein said further signal is fixed during normal operation of said system. .Iaddend. .Iadd.43. A method as defined in claim 17, wherein said step of generating said key number signal comprises periodically changing said key number signal. .Iaddend. .Iadd.44. A method as defined in claim 43, wherein said key number signal is changed at a rate slower than the signals of said first sequence of signals. .Iaddend. .Iadd.45. A communications system including a transmitter and a receiver, said system comprising:
a program source at said transmitter for providing a program signal representing program information:
first generator means at said transmitter for generating a first sequence of signals representing a first sequence of numbers common to all receivers receiving said program information;
key number means at said transmitter for providing a key number signal representing a key number common to all receivers receiving said program information;
transmit signal processing means at said transmitter responsive to at least said first sequence of signals for encrypting said program signal;
enciphering means at said transmitter for enciphering said first sequence of signals with said key number signal to provide an enciphered first signal sequence;
transmit means at said transmitter for transmitting said encrypted program signal and said enciphered first signal sequence;
means at said receiver for providing said key number signal;
receive deciphering means at said receiver for receiving said enciphered first signal sequence and said key number, deciphering said first signal sequence in accordance with said key number and providing said deciphered first signal sequence as an output; and
receive generating means at said receiver responsive to at least said output of said receive deciphering means for receiving and decrypting said encrypted program signal to obtain said program signal. .Iaddend.
.Iadd. A method of providing security in a signal transmission system between a transmitter and a receiver, said method comprising the steps of:
providing a program signal representing information;
generating a first sequence of signals representing a first sequence of numbers common to all receivers receiving said information;
providing a key number signal representing a key number common to all receivers receiving said information;
encrypting said program signal in accordance with at least said first sequence of signals;
enciphering said first sequence of signals with said key number signal to provide an enciphered first signal sequence;
transmitting said encrypted program signal and said enciphered first signal sequence to said receiver;
providing said key number signal at said receiver;
deciphering said first signal sequence at said receiver in accordance with said key number to obtain a deciphered first signal sequence; and
decrypting said encrypted program signal at said receiver in accordance with said first signal sequence to obtain said program signal. .Iaddend. .Iadd.47. A communications system including a transmitter and a receiver, said system comprising:
a program source at said transmitter for providing a program signal representing program information;
first generator means at said transmitter for generating a first sequence of signals representing a first sequence of numbers changing at least several times per minute;
key number means at said transmitter for providing a key number signal representing a key number;
transmit signal processing means at said transmitter responsive to at least said first sequence of signals for encrypting said program signal;
enciphering means at said transmitter for enciphering said first sequence of signals with said key number signal to provide an enciphered first signal sequence;
transmit means at said transmitter for transmitting said encryted program signal and said enciphered first signal sequence;
means at said receiver for providing said key number signal;
receive deciphering means at said receiver for receiving said enciphered first signal sequence and said key number, deciphering said first signal sequence in accordance with said key number and providing said deciphered first signal sequence as an output; and
receive generating means at said receiver responsive to at least said output of said receive deciphering means for receiving and decrypting said encrypted program signal to obtain said program signal. .Iaddend.
.Iadd. A communications system according to claim 47, wherein the numbers in said first sequence of numbers change approximately once per second. .Iaddend. .Iadd.49. A method of providing security in a signal transmission system between a transmitter and a receiver, said method comprising the steps of:
providing a program signal representing information;
generating a first sequence of signals representing a first sequence of numbers changing at least several times per minute;
providing a key number signal representing a key number;
encrypting said program signal in accordance with at least said first sequence of signals;
enciphering said first sequence of signals with said key number signal to provide an enciphered first signal sequence;
transmitting said encrypted program signal and said enciphered first signal sequence to said receiver;
providing said key number signal at said receiver;
deciphering said first signal sequence at said receiver in accordance with said key number to obtain a deciphered first signal sequence; and
decrypting said encrypted program signal at said receiver in accordance with said first signal sequence to obtain said program signal. .Iaddend.
.Iadd.50. A method according to claim 49, wherein the numbers in said first sequence of numbers change approximately once per second. .Iaddend.
US07/409,955 1981-11-19 1989-09-18 Security system for SSTV encryption Expired - Lifetime USRE33189E (en)

Priority Applications (2)

Application Number Priority Date Filing Date Title
US06/322,833 US4484027A (en) 1981-11-19 1981-11-19 Security system for SSTV encryption
US07/409,955 USRE33189E (en) 1981-11-19 1989-09-18 Security system for SSTV encryption

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US07/409,955 USRE33189E (en) 1981-11-19 1989-09-18 Security system for SSTV encryption

Related Parent Applications (2)

Application Number Title Priority Date Filing Date
US06/322,833 Reissue US4484027A (en) 1981-11-19 1981-11-19 Security system for SSTV encryption
US07192014 Continuation 1988-05-09

Publications (1)

Publication Number Publication Date
USRE33189E true USRE33189E (en) 1990-03-27

Family

ID=26983632

Family Applications (1)

Application Number Title Priority Date Filing Date
US07/409,955 Expired - Lifetime USRE33189E (en) 1981-11-19 1989-09-18 Security system for SSTV encryption

Country Status (1)

Country Link
US (1) USRE33189E (en)

Cited By (77)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5029207A (en) * 1990-02-01 1991-07-02 Scientific-Atlanta, Inc. External security module for a television signal decoder
US5029208A (en) * 1989-03-03 1991-07-02 Nec Corporation Cipher-key distribution system
US5185796A (en) * 1991-05-30 1993-02-09 Motorola, Inc. Encryption synchronization combined with encryption key identification
US5195136A (en) * 1991-09-30 1993-03-16 Motorola, Inc. Method and apparatus for data encryption or decryption
US5237610A (en) * 1990-02-01 1993-08-17 Scientific-Atlanta, Inc. Independent external security module for a digitally upgradeable television signal decoder
US5237611A (en) * 1992-07-23 1993-08-17 Crest Industries, Inc. Encryption/decryption apparatus with non-accessible table of keys
EP0560345A1 (en) * 1992-03-13 1993-09-15 Matsushita Electric Industrial Co., Ltd. A scramble code and a television receiver incorporating the same
WO1995026086A1 (en) * 1994-03-18 1995-09-28 Thomson Consumer Electronics, Inc. Data decryption apparatus in a subscription television signal receiving system
US5455862A (en) * 1993-12-02 1995-10-03 Crest Industries, Inc. Apparatus and method for encrypting communications without exchanging an encryption key
US5555308A (en) * 1994-11-10 1996-09-10 Angelika R. Levien Encryption of signals to insure viewership of commercials
FR2736485A1 (en) * 1995-07-03 1997-01-10 Thomson Multimedia Sa Method for processing a digital signal such as the output digital signal can not be derived from the entry digital signal and use thereof for access control and / or binary signature
US5627892A (en) * 1995-04-19 1997-05-06 General Instrument Corporation Of Delaware Data security scheme for point-to-point communication sessions
US5727065A (en) * 1994-11-14 1998-03-10 Hughes Electronics Deferred billing, broadcast, electronic document distribution system and method
USRE36181E (en) * 1993-06-30 1999-04-06 United Technologies Automotive, Inc. Pseudorandom number generation and crytographic authentication
USRE36752E (en) 1993-06-30 2000-06-27 United Technologies Automotive, Inc. Cryptographic authentication of transmitted messages using pseudorandom numbers
US6215873B1 (en) 1994-11-14 2001-04-10 Hughes Electronics Corporation Adapter for connecting computer to satellite antenna
US6292568B1 (en) 1966-12-16 2001-09-18 Scientific-Atlanta, Inc. Representing entitlements to service in a conditional access system
US20010053226A1 (en) * 1995-04-03 2001-12-20 Akins Glendon L. Representing entitlments to service in a conditional access system
US20020021807A1 (en) * 1994-04-01 2002-02-21 Mitsubishi Corporation Method for controlling database copyrights
US6381227B1 (en) 1993-06-17 2002-04-30 Gilat Florida Inc. Frame relay protocol-based multiplex switching scheme for satellite mesh network
US6424714B1 (en) 1995-12-04 2002-07-23 Scientific-Atlanta, Inc. Method and apparatus for providing conditional access in connection-oriented interactive networks with a multiplicity of service providers
US6424717B1 (en) 1995-04-03 2002-07-23 Scientific-Atlanta, Inc. Encryption devices for use in a conditional access system
US20020141591A1 (en) * 2001-03-28 2002-10-03 Philip Hawkes Method and apparatus for security in a data processing system
US20020141371A1 (en) * 2001-03-28 2002-10-03 Hsu Raymond T. Method and apparatus for transmission framing in a wireless communication system
US20020141365A1 (en) * 2001-03-28 2002-10-03 Leung Nikolai K.N. Method and apparatus for providing protocol options in a wireless communication system
US20020142757A1 (en) * 2001-03-28 2002-10-03 Leung Nikolai K.N. Method and apparatus for broadcast signaling in a wireless communication system
US20020186846A1 (en) * 2001-06-08 2002-12-12 Nokia Corporation Method for ensuring data transmission security, communication system and communication device
US20030014627A1 (en) * 1999-07-08 2003-01-16 Broadcom Corporation Distributed processing in a cryptography acceleration chip
US6510519B2 (en) 1995-04-03 2003-01-21 Scientific-Atlanta, Inc. Conditional access system
US6516412B2 (en) 1995-04-03 2003-02-04 Scientific-Atlanta, Inc. Authorization of services in a conditional access system
US6560340B1 (en) 1995-04-03 2003-05-06 Scientific-Atlanta, Inc. Method and apparatus for geographically limiting service in a conditional access system
US6587561B1 (en) 1998-03-04 2003-07-01 Nds Ltd. Key delivery in a secure broadcasting system
US20030144963A1 (en) * 1994-09-30 2003-07-31 Mitsubishi Corporation Data copyright management system
US20030161471A1 (en) * 2002-02-26 2003-08-28 Yu-Cheun Jou Method and apparatus for scrambling information bits on a channel in a communications system
US20040123120A1 (en) * 2002-12-18 2004-06-24 Broadcom Corporation Cryptography accelerator input interface data handling
US20040120527A1 (en) * 2001-08-20 2004-06-24 Hawkes Philip Michael Method and apparatus for security in a data processing system
US20040123119A1 (en) * 2002-12-18 2004-06-24 Broadcom Corporation Cryptography accelerator interface decoupling from cryptography processing cores
US20040123123A1 (en) * 2002-12-18 2004-06-24 Buer Mark L. Methods and apparatus for accessing security association information in a cryptography accelerator
US20040139337A1 (en) * 1995-04-03 2004-07-15 Pinder Howard G. Methods and apparatus for providing a partial dual-encrypted stream in a conditional access overlay system
US6771617B1 (en) 1993-06-17 2004-08-03 Gilat Satellite Networks, Ltd. Frame relay protocol-based multiplex switching scheme for satellite mesh network
US20050002531A1 (en) * 2003-04-23 2005-01-06 Michaelsen David L. Randomization-based encryption apparatus and method
US20050008159A1 (en) * 2003-07-07 2005-01-13 Francesco Grilli Secure registration for a multicast-broadcast-multimedia system (MBMS)
US20050010774A1 (en) * 2003-07-08 2005-01-13 Rose Gregory Gordon Apparatus and method for a secure broadcast system
WO2005006643A1 (en) * 2003-07-08 2005-01-20 Qualcomm, Incorporated Method and apparatus for security in a data processing system
US20050138379A1 (en) * 2003-09-02 2005-06-23 James Semple Method and apparatus for providing authenticated challenges for broadcast-multicast communications in a communication system
US20050152551A1 (en) * 1997-08-01 2005-07-14 Defreese Darryl L. Mechanism and apparatus for encapsulation of entitlement authorization in conditional access system
US20050216731A1 (en) * 1999-03-31 2005-09-29 Kabushiki Kaisha Toshiba Content distribution apparatus, content receiving apparatus, and content distribution method
US20060136717A1 (en) * 2004-12-20 2006-06-22 Mark Buer System and method for authentication via a proximate device
US20060133604A1 (en) * 2004-12-21 2006-06-22 Mark Buer System and method for securing data from a remote input device
US7113926B1 (en) * 1996-11-29 2006-09-26 Canon Kabushiki Kaisha Secure media on demand system whereby charge is determined in part from the periodicity of an encryption key
US20060233369A1 (en) * 1995-04-03 2006-10-19 Howard Pinder A partial dual encrypted stream utilizing program map tables
US20060282674A1 (en) * 1995-09-29 2006-12-14 Intarsia Software Llc Data management system
US7158058B1 (en) 2002-12-09 2007-01-02 Marvell International Ltd. Method and apparatus for generating a seed set in a data dependent seed selector
US20070033143A1 (en) * 1995-10-27 2007-02-08 Intarsia Software Llc Digital content management system and apparatus
US7191341B2 (en) 2002-12-18 2007-03-13 Broadcom Corporation Methods and apparatus for ordering data in a cryptography accelerator
US20070079145A1 (en) * 1994-10-27 2007-04-05 Intarsia Software Llc Data copyright management
US20070110228A1 (en) * 1994-04-01 2007-05-17 Makoto Saito Controlling database copyrights
US20070116282A1 (en) * 2001-08-20 2007-05-24 Qualcomm, Inc. Method and apparatus for security in a data processing system
US7397918B2 (en) 2000-05-22 2008-07-08 Nds Limited Dynamically shifting control word
US20080226073A1 (en) * 2001-10-09 2008-09-18 Qualcomm Incorporated Method and apparatus for security in a data processing system
US7434043B2 (en) 2002-12-18 2008-10-07 Broadcom Corporation Cryptography accelerator data routing unit
US20090147954A1 (en) * 2003-11-21 2009-06-11 Howard Pinder Partial Dual-Encryption Using Program Map Tables
US7600131B1 (en) 1999-07-08 2009-10-06 Broadcom Corporation Distributed processing in a cryptography acceleration chip
US20100048206A1 (en) * 2003-01-02 2010-02-25 Qualcomm Incorporated Method and apparatus for broadcast services in a communication system
US7734251B1 (en) 1981-11-03 2010-06-08 Personalized Media Communications, Llc Signal processing apparatus and methods
US20100142432A1 (en) * 2001-10-03 2010-06-10 Qualcomm Incorporated Method and Apparatus For Data Packet Transport In a Wireless Communication System Using an Internet Protocol
US7769344B1 (en) 1981-11-03 2010-08-03 Personalized Media Communications, Llc Signal processing apparatus and methods
USRE41657E1 (en) 1994-10-27 2010-09-07 Makoto Saito Data management system
US20100272124A1 (en) * 2001-10-12 2010-10-28 Qualcomm Incorporated Method and system for reduction of decoding complexity in a communication system
US7827109B2 (en) 1994-10-27 2010-11-02 Makoto Saito Digital content management system and apparatus
USRE42163E1 (en) 1994-04-01 2011-02-22 Intarsia Software Llc Data management system
US20110045864A1 (en) * 2001-03-28 2011-02-24 Qualcomm Incorporated Power control for point-to-multipoint services provided in communication systems
US8024810B2 (en) 1998-10-15 2011-09-20 Intarsia Software Llc Method and apparatus for protecting digital data by double re-encryption
USRE42921E1 (en) 1994-11-26 2011-11-15 Lg Electronics Inc. Copy prevention method and apparatus for digital video system
US20120063597A1 (en) * 2010-09-15 2012-03-15 Uponus Technologies, Llc. Apparatus and associated methodology for managing content control keys
USRE43993E1 (en) 1994-12-08 2013-02-12 Lg Electronics Inc. Method and apparatus for scrambling and/or descrambling digital video data and digital audio data using control data
US8548166B2 (en) 1995-04-03 2013-10-01 Anthony J. Wasilewski Method for partially encrypting program data

Citations (62)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3238297A (en) * 1951-06-08 1966-03-01 Zenith Radio Corp Subscription television system
US3649915A (en) * 1970-06-22 1972-03-14 Bell Telephone Labor Inc Digital data scrambler-descrambler apparatus for improved error performance
US3659046A (en) * 1968-05-15 1972-04-25 Sits Soc It Telecom Siemens Message scrambler for pcm communication system
US3717206A (en) * 1970-11-02 1973-02-20 Skiatron Elect & Tele Scrambled television
US3733431A (en) * 1971-03-10 1973-05-15 Electronic communication apparatus employing encripted signal distribution
US3769448A (en) * 1971-09-28 1973-10-30 Optical Systems Corp Audio encoding/decoding system for catv
US3801732A (en) * 1971-11-22 1974-04-02 J Reeves Method and apparatus for scrambled television
US3824332A (en) * 1972-02-18 1974-07-16 I Horowitz Pay television system
US3826863A (en) * 1973-02-09 1974-07-30 Oak Industries Inc Subscription television system using audio and video carrier reversal
US3852519A (en) * 1972-10-20 1974-12-03 Optical Systems Corp Video and audio encoding/decoding system employing suppressed carrier modulation
US3857997A (en) * 1973-03-08 1974-12-31 Oak Industries Inc Cable converter with phase lock loop techniques
US3911204A (en) * 1973-06-25 1975-10-07 Murray K Gordon Telephone addressed closed circuit television converter system
US3911216A (en) * 1973-12-17 1975-10-07 Honeywell Inf Systems Nonlinear code generator and decoder for transmitting data securely
US3914534A (en) * 1973-10-29 1975-10-21 Magnavox Co Methods and apparatus for scrambling and unscrambling premium television channels
US3916091A (en) * 1973-01-31 1975-10-28 Columbia Pictures Ind Inc Electronic communications system for supplementary video program distribution
US3919462A (en) * 1973-08-15 1975-11-11 System Dev Corp Method and apparatus for scrambling and unscrambling communication signals
US3934079A (en) * 1973-10-26 1976-01-20 Jerrold Electronics Corporation Bilateral communications system for distributing commerical and premium video signaling on an accountable basis
US3936593A (en) * 1974-08-05 1976-02-03 Gte Laboratories Incorporated Scrambler and decoder for a television signal
US3956615A (en) * 1974-06-25 1976-05-11 Ibm Corporation Transaction execution system with secure data storage and communications
US3982062A (en) * 1973-07-26 1976-09-21 Jerrold Electronics Corporation Video encription system
US3996418A (en) * 1974-08-05 1976-12-07 Gte Laboratories Incorporated Scrambler and decoder for secure television system
US3997718A (en) * 1973-02-01 1976-12-14 The Magnavox Company Premium interactive communication system
US3999005A (en) * 1974-12-26 1976-12-21 Ecom Corporation Secure transmission of AM or FM signals
US4024574A (en) * 1975-02-26 1977-05-17 Teleglobe Pay Tv System Inc. Validation method and apparatus for pay television systems
US4025948A (en) * 1975-02-25 1977-05-24 Teleglobe Pay-Tv System, Inc. Coding system for pay television apparatus
US4034402A (en) * 1974-07-01 1977-07-05 Hughes Aircraft Company Video scrambling system
US4058830A (en) * 1975-06-06 1977-11-15 Yves Maurice Guinet One way data transmission system
US4068264A (en) * 1976-07-19 1978-01-10 Teleglobe Pay-Tv System, Inc. Pay television system utilizing binary coding
US4070693A (en) * 1975-08-08 1978-01-24 Westinghouse Electric Corporation Secure television transmission system
US4075660A (en) * 1972-02-18 1978-02-21 Teleglobe Pay-Tv System, Inc. Pay television system with synchronization suppression
US4081831A (en) * 1976-04-08 1978-03-28 Twin County Trans-Video, Inc. High security subscription television system employing real time control of subscriber's program reception
US4081832A (en) * 1976-06-08 1978-03-28 Pay Television Corporation Pay television system, method and apparatus
US4091413A (en) * 1977-01-17 1978-05-23 Herman Richard E Security system for pay-TV channel
US4104486A (en) * 1976-06-29 1978-08-01 Martin John R System for accumulating data over nondedicated telephone lines
US4109281A (en) * 1976-05-07 1978-08-22 Pioneer Electronic Corporation Terminal device for catv
US4112464A (en) * 1977-05-11 1978-09-05 Oak Industries Inc. Subscription TV decoder logic system
US4115807A (en) * 1976-07-19 1978-09-19 Pires H George Telephone billing apparatus for a subscription television system
US4118669A (en) * 1976-10-15 1978-10-03 Premier Cablevision, Limited Remote disconnect-reconnect tap for cable television systems
US4126762A (en) * 1976-05-04 1978-11-21 Martin John R Method and system for accumulating data over nondedicated telephone lines
US4130833A (en) * 1977-04-11 1978-12-19 Teleglobe Pay-Tv System, Inc. Pay television system
US4148063A (en) * 1977-04-28 1979-04-03 Teleglobe Pay-Tv System, Inc. Method and apparatus for encoding audio signals in television systems
US4161751A (en) * 1977-05-19 1979-07-17 Ost Clarence S High-security cable television access system
US4163254A (en) * 1977-02-14 1979-07-31 Block Robert S Method and system for subscription television billing and access
US4200770A (en) * 1977-09-06 1980-04-29 Stanford University Cryptographic apparatus and method
US4225884A (en) * 1977-02-14 1980-09-30 Telease, Inc. Method and system for subscription television billing and access
GB2050021A (en) * 1979-05-21 1980-12-31 Atalla Technovations Method and means for securing the distribution of encoding keys
US4292650A (en) * 1979-10-29 1981-09-29 Zenith Radio Corporation Stv Subscriber address system
US4310720A (en) * 1978-03-31 1982-01-12 Pitney Bowes Inc. Computer accessing system
US4317957A (en) * 1980-03-10 1982-03-02 Marvin Sendrow System for authenticating users and devices in on-line transaction networks
US4323921A (en) * 1979-02-06 1982-04-06 Etablissement Public De Diffusion Dit "Telediffusion De France" System for transmitting information provided with means for controlling access to the information transmitted
US4337483A (en) * 1979-02-06 1982-06-29 Etablissement Public De Diffusion Dit "Telediffusion De France" Text video-transmission system provided with means for controlling access to the information
US4354201A (en) * 1979-06-15 1982-10-12 Etablissement Public De Diffusion Dit: Telediffusion De France Television system with access control
US4365110A (en) * 1979-06-05 1982-12-21 Communications Satellite Corporation Multiple-destinational cryptosystem for broadcast networks
US4388643A (en) * 1981-04-06 1983-06-14 Northern Telecom Limited Method of controlling scrambling and unscrambling in a pay TV system
US4398216A (en) * 1980-09-19 1983-08-09 Telease, Inc. Multiple signal transmission method and system, particularly for television
US4405942A (en) * 1981-02-25 1983-09-20 Telease, Inc. Method and system for secure transmission and reception of video information, particularly for television
US4410911A (en) * 1982-07-14 1983-10-18 Telease, Inc. Multiple signal transmission method and system, particularly for television
US4484027A (en) * 1981-11-19 1984-11-20 Communications Satellite Corporation Security system for SSTV encryption
US4528589A (en) * 1977-02-14 1985-07-09 Telease, Inc. Method and system for subscription television billing and access
US4531020A (en) * 1982-07-23 1985-07-23 Oak Industries Inc. Multi-layer encryption system for the broadcast of encrypted information
US4531021A (en) * 1980-06-19 1985-07-23 Oak Industries Inc. Two level encripting of RF signals
US4600942A (en) * 1982-07-29 1986-07-15 Telease, Inc. Secure coding and decoding system and method for television program signals

Patent Citations (64)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3238297A (en) * 1951-06-08 1966-03-01 Zenith Radio Corp Subscription television system
US3659046A (en) * 1968-05-15 1972-04-25 Sits Soc It Telecom Siemens Message scrambler for pcm communication system
US3649915A (en) * 1970-06-22 1972-03-14 Bell Telephone Labor Inc Digital data scrambler-descrambler apparatus for improved error performance
US3717206A (en) * 1970-11-02 1973-02-20 Skiatron Elect & Tele Scrambled television
US3733431A (en) * 1971-03-10 1973-05-15 Electronic communication apparatus employing encripted signal distribution
US3769448A (en) * 1971-09-28 1973-10-30 Optical Systems Corp Audio encoding/decoding system for catv
US3801732A (en) * 1971-11-22 1974-04-02 J Reeves Method and apparatus for scrambled television
US4075660A (en) * 1972-02-18 1978-02-21 Teleglobe Pay-Tv System, Inc. Pay television system with synchronization suppression
US3824332A (en) * 1972-02-18 1974-07-16 I Horowitz Pay television system
US3852519A (en) * 1972-10-20 1974-12-03 Optical Systems Corp Video and audio encoding/decoding system employing suppressed carrier modulation
US3916091A (en) * 1973-01-31 1975-10-28 Columbia Pictures Ind Inc Electronic communications system for supplementary video program distribution
US3997718A (en) * 1973-02-01 1976-12-14 The Magnavox Company Premium interactive communication system
US3826863A (en) * 1973-02-09 1974-07-30 Oak Industries Inc Subscription television system using audio and video carrier reversal
US3857997A (en) * 1973-03-08 1974-12-31 Oak Industries Inc Cable converter with phase lock loop techniques
US3911204A (en) * 1973-06-25 1975-10-07 Murray K Gordon Telephone addressed closed circuit television converter system
US3982062A (en) * 1973-07-26 1976-09-21 Jerrold Electronics Corporation Video encription system
US3919462A (en) * 1973-08-15 1975-11-11 System Dev Corp Method and apparatus for scrambling and unscrambling communication signals
US3934079A (en) * 1973-10-26 1976-01-20 Jerrold Electronics Corporation Bilateral communications system for distributing commerical and premium video signaling on an accountable basis
US3914534A (en) * 1973-10-29 1975-10-21 Magnavox Co Methods and apparatus for scrambling and unscrambling premium television channels
US3911216A (en) * 1973-12-17 1975-10-07 Honeywell Inf Systems Nonlinear code generator and decoder for transmitting data securely
US3956615A (en) * 1974-06-25 1976-05-11 Ibm Corporation Transaction execution system with secure data storage and communications
US4034402A (en) * 1974-07-01 1977-07-05 Hughes Aircraft Company Video scrambling system
US3936593A (en) * 1974-08-05 1976-02-03 Gte Laboratories Incorporated Scrambler and decoder for a television signal
US3996418A (en) * 1974-08-05 1976-12-07 Gte Laboratories Incorporated Scrambler and decoder for secure television system
US3999005A (en) * 1974-12-26 1976-12-21 Ecom Corporation Secure transmission of AM or FM signals
US4025948A (en) * 1975-02-25 1977-05-24 Teleglobe Pay-Tv System, Inc. Coding system for pay television apparatus
US4024574A (en) * 1975-02-26 1977-05-17 Teleglobe Pay Tv System Inc. Validation method and apparatus for pay television systems
US4091417A (en) * 1975-02-26 1978-05-23 Teleglobe Pay-Tv System, Inc. Decoder mode validation apparatus for pay television systems
US4058830A (en) * 1975-06-06 1977-11-15 Yves Maurice Guinet One way data transmission system
US4070693A (en) * 1975-08-08 1978-01-24 Westinghouse Electric Corporation Secure television transmission system
US4081831A (en) * 1976-04-08 1978-03-28 Twin County Trans-Video, Inc. High security subscription television system employing real time control of subscriber's program reception
US4126762A (en) * 1976-05-04 1978-11-21 Martin John R Method and system for accumulating data over nondedicated telephone lines
US4109281A (en) * 1976-05-07 1978-08-22 Pioneer Electronic Corporation Terminal device for catv
US4081832A (en) * 1976-06-08 1978-03-28 Pay Television Corporation Pay television system, method and apparatus
US4104486A (en) * 1976-06-29 1978-08-01 Martin John R System for accumulating data over nondedicated telephone lines
US4068264A (en) * 1976-07-19 1978-01-10 Teleglobe Pay-Tv System, Inc. Pay television system utilizing binary coding
US4115807A (en) * 1976-07-19 1978-09-19 Pires H George Telephone billing apparatus for a subscription television system
US4118669A (en) * 1976-10-15 1978-10-03 Premier Cablevision, Limited Remote disconnect-reconnect tap for cable television systems
US4091413A (en) * 1977-01-17 1978-05-23 Herman Richard E Security system for pay-TV channel
US4225884A (en) * 1977-02-14 1980-09-30 Telease, Inc. Method and system for subscription television billing and access
US4528589A (en) * 1977-02-14 1985-07-09 Telease, Inc. Method and system for subscription television billing and access
US4163254A (en) * 1977-02-14 1979-07-31 Block Robert S Method and system for subscription television billing and access
US4130833A (en) * 1977-04-11 1978-12-19 Teleglobe Pay-Tv System, Inc. Pay television system
US4148063A (en) * 1977-04-28 1979-04-03 Teleglobe Pay-Tv System, Inc. Method and apparatus for encoding audio signals in television systems
US4112464B1 (en) * 1977-05-11 1988-09-27
US4112464A (en) * 1977-05-11 1978-09-05 Oak Industries Inc. Subscription TV decoder logic system
US4161751A (en) * 1977-05-19 1979-07-17 Ost Clarence S High-security cable television access system
US4200770A (en) * 1977-09-06 1980-04-29 Stanford University Cryptographic apparatus and method
US4310720A (en) * 1978-03-31 1982-01-12 Pitney Bowes Inc. Computer accessing system
US4337483A (en) * 1979-02-06 1982-06-29 Etablissement Public De Diffusion Dit "Telediffusion De France" Text video-transmission system provided with means for controlling access to the information
US4323921A (en) * 1979-02-06 1982-04-06 Etablissement Public De Diffusion Dit "Telediffusion De France" System for transmitting information provided with means for controlling access to the information transmitted
GB2050021A (en) * 1979-05-21 1980-12-31 Atalla Technovations Method and means for securing the distribution of encoding keys
US4365110A (en) * 1979-06-05 1982-12-21 Communications Satellite Corporation Multiple-destinational cryptosystem for broadcast networks
US4354201A (en) * 1979-06-15 1982-10-12 Etablissement Public De Diffusion Dit: Telediffusion De France Television system with access control
US4292650A (en) * 1979-10-29 1981-09-29 Zenith Radio Corporation Stv Subscriber address system
US4317957A (en) * 1980-03-10 1982-03-02 Marvin Sendrow System for authenticating users and devices in on-line transaction networks
US4531021A (en) * 1980-06-19 1985-07-23 Oak Industries Inc. Two level encripting of RF signals
US4398216A (en) * 1980-09-19 1983-08-09 Telease, Inc. Multiple signal transmission method and system, particularly for television
US4405942A (en) * 1981-02-25 1983-09-20 Telease, Inc. Method and system for secure transmission and reception of video information, particularly for television
US4388643A (en) * 1981-04-06 1983-06-14 Northern Telecom Limited Method of controlling scrambling and unscrambling in a pay TV system
US4484027A (en) * 1981-11-19 1984-11-20 Communications Satellite Corporation Security system for SSTV encryption
US4410911A (en) * 1982-07-14 1983-10-18 Telease, Inc. Multiple signal transmission method and system, particularly for television
US4531020A (en) * 1982-07-23 1985-07-23 Oak Industries Inc. Multi-layer encryption system for the broadcast of encrypted information
US4600942A (en) * 1982-07-29 1986-07-15 Telease, Inc. Secure coding and decoding system and method for television program signals

Non-Patent Citations (12)

* Cited by examiner, † Cited by third party
Title
F. Heinrich, "The Network Security Center: A System Level Approach to Computer Security", National Bureau of Standards Special Publication 500-21, vol. 1, Jan. 1978.
F. Heinrich, The Network Security Center: A System Level Approach to Computer Security , National Bureau of Standards Special Publication 500 21, vol. 1, Jan. 1978. *
I. Ingemarson et al, "Encryption and Authentication in On-Board Processing Satellite Communication Systems," IEEE Transactions on Communications, vol. COM-29, No. 11, Nov. 1981, pp. 1684-1687.
I. Ingemarson et al, Encryption and Authentication in On Board Processing Satellite Communication Systems, IEEE Transactions on Communications, vol. COM 29, No. 11, Nov. 1981, pp. 1684 1687. *
J. Everton, "Adaptation of the Basic Hierarchy for Encryption Key Management to Serve Applications With Conflicting Requirements," IEEE, 1979, pp. 186-191.
J. Everton, Adaptation of the Basic Hierarchy for Encryption Key Management to Serve Applications With Conflicting Requirements, IEEE, 1979, pp. 186 191. *
M. Sendrow, "A Method of Authentication in EFT Networks Using DES Without Downline Loading of Working Keys," 1980, IEEE, pp. 168-175.
M. Sendrow, A Method of Authentication in EFT Networks Using DES Without Downline Loading of Working Keys, 1980, IEEE, pp. 168 175. *
S. Kent, "Encryption-Based Protection Protocols for Interactive User-Computer Communication," NTIS Technical Report 162, May 1976.
S. Kent, "Security Requirements and Protocols for a Broadcast Scenario," IEEE Transactions on Communications, vol. COM-29, No. 6, Jun. '81, pp. 778-786.
S. Kent, Encryption Based Protection Protocols for Interactive User Computer Communication, NTIS Technical Report 162, May 1976. *
S. Kent, Security Requirements and Protocols for a Broadcast Scenario, IEEE Transactions on Communications, vol. COM 29, No. 6, Jun. 81, pp. 778 786. *

Cited By (240)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6292568B1 (en) 1966-12-16 2001-09-18 Scientific-Atlanta, Inc. Representing entitlements to service in a conditional access system
US7864956B1 (en) 1981-11-03 2011-01-04 Personalized Media Communications, Llc Signal processing apparatus and methods
US7953223B1 (en) 1981-11-03 2011-05-31 Personalized Media Communications, L.L.C. Signal processing apparatus and methods
US7940931B1 (en) 1981-11-03 2011-05-10 Personalized Media Communications LLC Signal processing apparatus and methods
US7926084B1 (en) 1981-11-03 2011-04-12 Personalized Media Communications LLC Signal processing apparatus and methods
US8060903B1 (en) 1981-11-03 2011-11-15 Personalized Media PMC Communications, L.L.C. Signal processing apparatus and methods
US7908638B1 (en) 1981-11-03 2011-03-15 Personalized Media Communications LLC Signal processing apparatus and methods
US7889865B1 (en) 1981-11-03 2011-02-15 Personalized Media Communications, L.L.C. Signal processing apparatus and methods
US7870581B1 (en) 1981-11-03 2011-01-11 Personalized Media Communications, Llc Signal processing apparatus and methods
US7864248B1 (en) 1981-11-03 2011-01-04 Personalized Media Communications, Llc Signal processing apparatus and methods
US7865920B1 (en) 1981-11-03 2011-01-04 Personalized Media Communications LLC Signal processing apparatus and methods
US7861278B1 (en) 1981-11-03 2010-12-28 Personalized Media Communications, Llc Signal processing apparatus and methods
US9674560B1 (en) 1981-11-03 2017-06-06 Personalized Media Communications LLC Signal processing apparatus and methods
US9294205B1 (en) 1981-11-03 2016-03-22 Personalized Media Communications LLC Signal processing apparatus and methods
US7861263B1 (en) 1981-11-03 2010-12-28 Personalized Media Communications, Llc Signal processing apparatus and methods
US7860131B1 (en) 1981-11-03 2010-12-28 Personalized Media Communications, Llc Signal processing apparatus and methods
US7860249B1 (en) 1981-11-03 2010-12-28 Personalized Media Communications LLC Signal processing apparatus and methods
US7856650B1 (en) 1981-11-03 2010-12-21 Personalized Media Communications, Llc Signal processing apparatus and methods
US7856649B1 (en) 1981-11-03 2010-12-21 Personalized Media Communications, Llc Signal processing apparatus and methods
US7992169B1 (en) 1981-11-03 2011-08-02 Personalized Media Communications LLC Signal processing apparatus and methods
US7849493B1 (en) 1981-11-03 2010-12-07 Personalized Media Communications, Llc Signal processing apparatus and methods
US8046791B1 (en) 1981-11-03 2011-10-25 Personalized Media Communications, Llc Signal processing apparatus and methods
US7849480B1 (en) 1981-11-03 2010-12-07 Personalized Media Communications LLC Signal processing apparatus and methods
US7849479B1 (en) 1981-11-03 2010-12-07 Personalized Media Communications, Llc Signal processing apparatus and methods
US7844995B1 (en) 1981-11-03 2010-11-30 Personalized Media Communications, Llc Signal processing apparatus and methods
US7840976B1 (en) 1981-11-03 2010-11-23 Personalized Media Communications, Llc Signal processing apparatus and methods
US9210370B1 (en) 1981-11-03 2015-12-08 Personalized Media Communications LLC Signal processing apparatus and methods
US7836480B1 (en) 1981-11-03 2010-11-16 Personalized Media Communications, Llc Signal processing apparatus and methods
US9038124B1 (en) 1981-11-03 2015-05-19 Personalized Media Communications, Llc Signal processing apparatus and methods
US8973034B1 (en) 1981-11-03 2015-03-03 Personalized Media Communications LLC Signal processing apparatus and methods
US7831204B1 (en) 1981-11-03 2010-11-09 Personalized Media Communications, Llc Signal processing apparatus and methods
US8914825B1 (en) 1981-11-03 2014-12-16 Personalized Media Communications LLC Signal processing apparatus and methods
US8893177B1 (en) 1981-11-03 2014-11-18 {Personalized Media Communications, LLC Signal processing apparatus and methods
US8869229B1 (en) 1981-11-03 2014-10-21 Personalized Media Communications, Llc Signal processing apparatus and methods
US7830925B1 (en) 1981-11-03 2010-11-09 Personalized Media Communications, Llc Signal processing apparatus and methods
US7827586B1 (en) 1981-11-03 2010-11-02 Personalized Media Communications, Llc Signal processing apparatus and methods
US7827587B1 (en) 1981-11-03 2010-11-02 Personalized Media Communications, Llc Signal processing apparatus and methods
US7823175B1 (en) 1981-11-03 2010-10-26 Personalized Media Communications LLC Signal processing apparatus and methods
US7818776B1 (en) 1981-11-03 2010-10-19 Personalized Media Communications, Llc Signal processing apparatus and methods
US8869228B1 (en) 1981-11-03 2014-10-21 Personalized Media Communications, Llc Signal processing apparatus and methods
US7818761B1 (en) 1981-11-03 2010-10-19 Personalized Media Communications, Llc Signal processing apparatus and methods
US8839293B1 (en) 1981-11-03 2014-09-16 Personalized Media Communications, Llc Signal processing apparatus and methods
US7818778B1 (en) 1981-11-03 2010-10-19 Personalized Media Communications, Llc Signal processing apparatus and methods
US7817208B1 (en) 1981-11-03 2010-10-19 Personalized Media Communications, Llc Signal processing apparatus and methods
US7814526B1 (en) 1981-11-03 2010-10-12 Personalized Media Communications, Llc Signal processing apparatus and methods
US8112782B1 (en) 1981-11-03 2012-02-07 Personalized Media Communications, Llc Signal processing apparatus and methods
US8804727B1 (en) 1981-11-03 2014-08-12 Personalized Media Communications, Llc Signal processing apparatus and methods
US8752088B1 (en) 1981-11-03 2014-06-10 Personalized Media Communications LLC Signal processing apparatus and methods
US8739241B1 (en) 1981-11-03 2014-05-27 Personalized Media Communications LLC Signal processing apparatus and methods
US8713624B1 (en) 1981-11-03 2014-04-29 Personalized Media Communications LLC Signal processing apparatus and methods
US7810115B1 (en) 1981-11-03 2010-10-05 Personalized Media Communications, Llc Signal processing apparatus and methods
US7805738B1 (en) 1981-11-03 2010-09-28 Personalized Media Communications, Llc Signal processing apparatus and methods
US10334292B1 (en) 1981-11-03 2019-06-25 Personalized Media Communications LLC Signal processing apparatus and methods
US8683539B1 (en) 1981-11-03 2014-03-25 Personalized Media Communications, Llc Signal processing apparatus and methods
US8675775B1 (en) 1981-11-03 2014-03-18 Personalized Media Communications, Llc Signal processing apparatus and methods
US8646001B1 (en) 1981-11-03 2014-02-04 Personalized Media Communications, Llc Signal processing apparatus and methods
US8640184B1 (en) 1981-11-03 2014-01-28 Personalized Media Communications, Llc Signal processing apparatus and methods
US8635644B1 (en) 1981-11-03 2014-01-21 Personalized Media Communications LLC Signal processing apparatus and methods
US8621547B1 (en) 1981-11-03 2013-12-31 Personalized Media Communications, Llc Signal processing apparatus and methods
US7805749B1 (en) 1981-11-03 2010-09-28 Personalized Media Communications, Llc Signal processing apparatus and methods
US8613034B1 (en) 1981-11-03 2013-12-17 Personalized Media Communications, Llc Signal processing apparatus and methods
US7805748B1 (en) 1981-11-03 2010-09-28 Personalized Media Communications, Llc Signal processing apparatus and methods
US8607296B1 (en) 1981-11-03 2013-12-10 Personalized Media Communications LLC Signal processing apparatus and methods
US8601528B1 (en) 1981-11-03 2013-12-03 Personalized Media Communications, L.L.C. Signal processing apparatus and methods
US8191091B1 (en) 1981-11-03 2012-05-29 Personalized Media Communications, Llc Signal processing apparatus and methods
US8587720B1 (en) 1981-11-03 2013-11-19 Personalized Media Communications LLC Signal processing apparatus and methods
US7801304B1 (en) 1981-11-03 2010-09-21 Personalized Media Communications, Llc Signal processing apparatus and methods
US8584162B1 (en) 1981-11-03 2013-11-12 Personalized Media Communications LLC Signal processing apparatus and methods
US7797717B1 (en) 1981-11-03 2010-09-14 Personalized Media Communications, Llc Signal processing apparatus and methods
US8572671B1 (en) 1981-11-03 2013-10-29 Personalized Media Communications LLC Signal processing apparatus and methods
US7793332B1 (en) 1981-11-03 2010-09-07 Personalized Media Communications, Llc Signal processing apparatus and methods
US8566868B1 (en) 1981-11-03 2013-10-22 Personalized Media Communications, L.L.C. Signal processing apparatus and methods
US7784082B1 (en) 1981-11-03 2010-08-24 Personalized Media Communications, Llc Signal processing apparatus and methods
US7783252B1 (en) 1981-11-03 2010-08-24 Personalized Media Communications, Llc Signal processing apparatus and methods
US7774809B1 (en) 1981-11-03 2010-08-10 Personalized Media Communications, Llc Signal processing apparatus and method
US7769344B1 (en) 1981-11-03 2010-08-03 Personalized Media Communications, Llc Signal processing apparatus and methods
US8559635B1 (en) 1981-11-03 2013-10-15 Personalized Media Communications, L.L.C. Signal processing apparatus and methods
US7769170B1 (en) 1981-11-03 2010-08-03 Personalized Media Communications, Llc Signal processing apparatus and methods
US7764685B1 (en) 1981-11-03 2010-07-27 Personalized Media Communications, L.L.C. Signal processing apparatus and methods
US7752650B1 (en) 1981-11-03 2010-07-06 Personalized Media Communications, Llc Signal processing apparatus and methods
US7752649B1 (en) 1981-11-03 2010-07-06 Personalized Media Communications, Llc Signal processing apparatus and methods
US8558950B1 (en) 1981-11-03 2013-10-15 Personalized Media Communications LLC Signal processing apparatus and methods
US7747217B1 (en) 1981-11-03 2010-06-29 Personalized Media Communications, Llc Signal processing apparatus and methods
US7734251B1 (en) 1981-11-03 2010-06-08 Personalized Media Communications, Llc Signal processing apparatus and methods
US7761890B1 (en) 1981-11-03 2010-07-20 Personalized Media Communications, Llc Signal processing apparatus and methods
US8395707B1 (en) 1981-11-03 2013-03-12 Personalized Media Communications LLC Signal processing apparatus and methods
US7818777B1 (en) 1981-11-03 2010-10-19 Personalized Media Communications, Llc Signal processing apparatus and methods
US7966640B1 (en) 1987-09-11 2011-06-21 Personalized Media Communications, Llc Signal processing apparatus and methods
US7958527B1 (en) 1987-09-11 2011-06-07 Personalized Media Communications, Llc Signal processing apparatus and methods
US5029208A (en) * 1989-03-03 1991-07-02 Nec Corporation Cipher-key distribution system
US5237610A (en) * 1990-02-01 1993-08-17 Scientific-Atlanta, Inc. Independent external security module for a digitally upgradeable television signal decoder
US5029207A (en) * 1990-02-01 1991-07-02 Scientific-Atlanta, Inc. External security module for a television signal decoder
USRE39166E1 (en) * 1990-02-01 2006-07-11 Scientific-Atlanta, Inc. External security module for a television signal decoder
US5185796A (en) * 1991-05-30 1993-02-09 Motorola, Inc. Encryption synchronization combined with encryption key identification
US5195136A (en) * 1991-09-30 1993-03-16 Motorola, Inc. Method and apparatus for data encryption or decryption
US5355409A (en) * 1992-03-13 1994-10-11 Matsushita Electric Industrial Co., Ltd. Scramble codec and a television receiver incorporating the same
EP0560345A1 (en) * 1992-03-13 1993-09-15 Matsushita Electric Industrial Co., Ltd. A scramble code and a television receiver incorporating the same
US5237611A (en) * 1992-07-23 1993-08-17 Crest Industries, Inc. Encryption/decryption apparatus with non-accessible table of keys
WO1994003003A1 (en) * 1992-07-23 1994-02-03 Crest Industries, Inc. Encryption/decryption apparatus with non-accessible table of keys
US20040240406A1 (en) * 1993-06-17 2004-12-02 Gilat Satellite Networks, Ltd. Frame relay protocol-based multiplex switching scheme for satellite mesh network
US6381227B1 (en) 1993-06-17 2002-04-30 Gilat Florida Inc. Frame relay protocol-based multiplex switching scheme for satellite mesh network
US7583626B2 (en) 1993-06-17 2009-09-01 Gilat Satellite Networks, Ltd. Multiplex switching scheme for communications network
US6771617B1 (en) 1993-06-17 2004-08-03 Gilat Satellite Networks, Ltd. Frame relay protocol-based multiplex switching scheme for satellite mesh network
US7321572B2 (en) 1993-06-17 2008-01-22 Gilat Satellite Networks, Ltd. Frame relay protocol-based multiplex switching scheme for satellite mesh network
US20090316618A1 (en) * 1993-06-17 2009-12-24 Gilat Satellite Networks, Ltd. Multiplex Switching Scheme for Communications Network
US6625130B2 (en) 1993-06-17 2003-09-23 Gilat Satellite Networks, Ltd. Frame relay protocol-based multiplex switching scheme for satellite mesh network
US8068472B2 (en) 1993-06-17 2011-11-29 Gilat Satellite Networks, Ltd Multiplex switching scheme for communications network
USRE36752E (en) 1993-06-30 2000-06-27 United Technologies Automotive, Inc. Cryptographic authentication of transmitted messages using pseudorandom numbers
USRE36181E (en) * 1993-06-30 1999-04-06 United Technologies Automotive, Inc. Pseudorandom number generation and crytographic authentication
US5455862A (en) * 1993-12-02 1995-10-03 Crest Industries, Inc. Apparatus and method for encrypting communications without exchanging an encryption key
WO1995026086A1 (en) * 1994-03-18 1995-09-28 Thomson Consumer Electronics, Inc. Data decryption apparatus in a subscription television signal receiving system
US20070110228A1 (en) * 1994-04-01 2007-05-17 Makoto Saito Controlling database copyrights
US20070061267A1 (en) * 1994-04-01 2007-03-15 Makoto Saito Controlling database copyrights
US7979354B2 (en) 1994-04-01 2011-07-12 Intarsia Software Llc Controlling database copyrights
US7447914B1 (en) 1994-04-01 2008-11-04 Intarsia Software Llc Method for controlling database copyrights
US7383447B2 (en) 1994-04-01 2008-06-03 Intarsia Software Llc Method for controlling database copyrights
US20020021807A1 (en) * 1994-04-01 2002-02-21 Mitsubishi Corporation Method for controlling database copyrights
US8554684B2 (en) 1994-04-01 2013-10-08 Intarsia Software Llc Controlling database copyrights
US7730324B2 (en) 1994-04-01 2010-06-01 Makoto Saito Method for controlling database copyrights
US7730323B2 (en) 1994-04-01 2010-06-01 Makoto Saito Controlling database copyrights
USRE42163E1 (en) 1994-04-01 2011-02-22 Intarsia Software Llc Data management system
US8352373B2 (en) 1994-09-30 2013-01-08 Intarsia Software Llc Data copyright management system
US20070038575A1 (en) * 1994-09-30 2007-02-15 Intarsia Software Llc Data copyright management system
US20030144963A1 (en) * 1994-09-30 2003-07-31 Mitsubishi Corporation Data copyright management system
US7302415B1 (en) 1994-09-30 2007-11-27 Intarsia Llc Data copyright management system
US9245260B2 (en) 1994-10-27 2016-01-26 Xylon Llc Data copyright management
US7986785B2 (en) 1994-10-27 2011-07-26 Intarsia Software Llc Data management
US8407782B2 (en) 1994-10-27 2013-03-26 Intarsia Software Llc Data copyright management
US20110047626A1 (en) * 1994-10-27 2011-02-24 Makoto Saito Digital content management system and apparatus
USRE43599E1 (en) 1994-10-27 2012-08-21 Intarsia Software Llc Data management system
US20070079145A1 (en) * 1994-10-27 2007-04-05 Intarsia Software Llc Data copyright management
US20070088960A1 (en) * 1994-10-27 2007-04-19 Intarsia Software Llc Data copyright management
US7827109B2 (en) 1994-10-27 2010-11-02 Makoto Saito Digital content management system and apparatus
USRE41657E1 (en) 1994-10-27 2010-09-07 Makoto Saito Data management system
US8448254B2 (en) 1994-10-27 2013-05-21 Intarsia Software Llc Digital content management system and apparatus
US5555308A (en) * 1994-11-10 1996-09-10 Angelika R. Levien Encryption of signals to insure viewership of commercials
US6307937B1 (en) 1994-11-14 2001-10-23 Hughes Electronics Corporation Method and apparatus for an adapter card providing conditional access in a communication system
US6728878B2 (en) 1994-11-14 2004-04-27 Hughes Electronics Corporation Deferred billing, broadcast, electronic document distribution system and method
US6215873B1 (en) 1994-11-14 2001-04-10 Hughes Electronics Corporation Adapter for connecting computer to satellite antenna
US5727065A (en) * 1994-11-14 1998-03-10 Hughes Electronics Deferred billing, broadcast, electronic document distribution system and method
US6337911B1 (en) 1994-11-14 2002-01-08 Hughes Electronics Corporation Deferred billing, broadcast, electronic document distribution system and method
US6331979B1 (en) 1994-11-14 2001-12-18 Hughes Electronics Corporation Method and apparatus for connecting computer to satellite antenna
USRE42951E1 (en) 1994-11-26 2011-11-22 Lg Electronics Inc. Copy prevention method and apparatus for digital video system
USRE42921E1 (en) 1994-11-26 2011-11-15 Lg Electronics Inc. Copy prevention method and apparatus for digital video system
USRE42922E1 (en) 1994-11-26 2011-11-15 Lg Electronics Inc. Copy prevention method and apparatus for digital video system
USRE42950E1 (en) 1994-11-26 2011-11-22 Lg Electronics Inc. Copy prevention method and apparatus for digital video system
USRE44068E1 (en) * 1994-12-08 2013-03-12 Lg Electronics Inc. Method and apparatus for descrambling digital video data and digital audio data using control data
USRE44106E1 (en) 1994-12-08 2013-03-26 Lg Electronics Inc Copy prevention method and apparatus of a digital recording/reproducing system
USRE44121E1 (en) 1994-12-08 2013-04-02 Lg Electronics Inc. Copy prevention method and apparatus of a digital recording/reproducing system
USRE43993E1 (en) 1994-12-08 2013-02-12 Lg Electronics Inc. Method and apparatus for scrambling and/or descrambling digital video data and digital audio data using control data
US6510519B2 (en) 1995-04-03 2003-01-21 Scientific-Atlanta, Inc. Conditional access system
US20010053226A1 (en) * 1995-04-03 2001-12-20 Akins Glendon L. Representing entitlments to service in a conditional access system
US7224798B2 (en) 1995-04-03 2007-05-29 Scientific-Atlanta, Inc. Methods and apparatus for providing a partial dual-encrypted stream in a conditional access overlay system
US20030074565A1 (en) * 1995-04-03 2003-04-17 Wasilewski Anthony J. Authorization of services in a conditional access system
US20040139337A1 (en) * 1995-04-03 2004-07-15 Pinder Howard G. Methods and apparatus for providing a partial dual-encrypted stream in a conditional access overlay system
US6526508B2 (en) 1995-04-03 2003-02-25 Scientific-Atlanta, Inc. Source authentication of download information in a conditional access system
US6744892B2 (en) 1995-04-03 2004-06-01 Scientific-Atlanta, Inc. Method and apparatus for geographically limiting service in a conditional access system
US8548166B2 (en) 1995-04-03 2013-10-01 Anthony J. Wasilewski Method for partially encrypting program data
US20070286417A1 (en) * 1995-04-03 2007-12-13 Pinder Howard G Methods and apparatus for providing a partial dual-encrypted stream in a conditional access overlay system
US8542830B2 (en) 1995-04-03 2013-09-24 Anthony J. Wasilewski Method for partially encrypting program data
US8577033B2 (en) 1995-04-03 2013-11-05 Anthony J. Wasilewski Method for partially encrypting program data
US6516412B2 (en) 1995-04-03 2003-02-04 Scientific-Atlanta, Inc. Authorization of services in a conditional access system
US20060233369A1 (en) * 1995-04-03 2006-10-19 Howard Pinder A partial dual encrypted stream utilizing program map tables
US6971008B2 (en) 1995-04-03 2005-11-29 Scientific-Atlanta, Inc. Authorization of services in a conditional access system
US6424717B1 (en) 1995-04-03 2002-07-23 Scientific-Atlanta, Inc. Encryption devices for use in a conditional access system
US20040003008A1 (en) * 1995-04-03 2004-01-01 Wasilewski Anthony J. Method for partially encrypting program data
US7496198B2 (en) 1995-04-03 2009-02-24 Cisco Technology, Inc. Partial dual encrypted stream utilizing program map tables
US6937729B2 (en) 1995-04-03 2005-08-30 Scientific-Atlanta, Inc. Representing entitlements to service in a conditional access system
US6560340B1 (en) 1995-04-03 2003-05-06 Scientific-Atlanta, Inc. Method and apparatus for geographically limiting service in a conditional access system
US7805399B2 (en) 1995-04-03 2010-09-28 Pinder Howard G Methods and apparatus for providing a partial dual-encrypted stream in a conditional access overlay system
US5627892A (en) * 1995-04-19 1997-05-06 General Instrument Corporation Of Delaware Data security scheme for point-to-point communication sessions
FR2736485A1 (en) * 1995-07-03 1997-01-10 Thomson Multimedia Sa Method for processing a digital signal such as the output digital signal can not be derived from the entry digital signal and use thereof for access control and / or binary signature
US5764771A (en) * 1995-07-03 1998-06-09 Thomson Multimedia S.A. Method for processing a digital signal in a so-called secure communication system and use of this method for access control and/or binary signature
US20060282674A1 (en) * 1995-09-29 2006-12-14 Intarsia Software Llc Data management system
US8595502B2 (en) 1995-09-29 2013-11-26 Intarsia Software Llc Data management system
US20070033143A1 (en) * 1995-10-27 2007-02-08 Intarsia Software Llc Digital content management system and apparatus
US7801817B2 (en) 1995-10-27 2010-09-21 Makoto Saito Digital content management system and apparatus
US6424714B1 (en) 1995-12-04 2002-07-23 Scientific-Atlanta, Inc. Method and apparatus for providing conditional access in connection-oriented interactive networks with a multiplicity of service providers
US7113926B1 (en) * 1996-11-29 2006-09-26 Canon Kabushiki Kaisha Secure media on demand system whereby charge is determined in part from the periodicity of an encryption key
US8095785B2 (en) 1997-08-01 2012-01-10 Defreese Darryl L Authentication of entitlement authorization in conditional access systems
US7515712B2 (en) 1997-08-01 2009-04-07 Cisco Technology, Inc. Mechanism and apparatus for encapsulation of entitlement authorization in conditional access system
US20090150673A1 (en) * 1997-08-01 2009-06-11 Defreese Darryl L Authentication of Entitlement Authorization in Conditional Access Systems
US20050152551A1 (en) * 1997-08-01 2005-07-14 Defreese Darryl L. Mechanism and apparatus for encapsulation of entitlement authorization in conditional access system
US6587561B1 (en) 1998-03-04 2003-07-01 Nds Ltd. Key delivery in a secure broadcasting system
US8024810B2 (en) 1998-10-15 2011-09-20 Intarsia Software Llc Method and apparatus for protecting digital data by double re-encryption
US20050216731A1 (en) * 1999-03-31 2005-09-29 Kabushiki Kaisha Toshiba Content distribution apparatus, content receiving apparatus, and content distribution method
US20030014627A1 (en) * 1999-07-08 2003-01-16 Broadcom Corporation Distributed processing in a cryptography acceleration chip
US7996670B1 (en) 1999-07-08 2011-08-09 Broadcom Corporation Classification engine in a cryptography acceleration chip
US7600131B1 (en) 1999-07-08 2009-10-06 Broadcom Corporation Distributed processing in a cryptography acceleration chip
US7916865B2 (en) 2000-05-22 2011-03-29 Nds Limited Dynamically shifting control word
US20080240431A1 (en) * 2000-05-22 2008-10-02 Nds Limited Dynamically shifting control word
US7397918B2 (en) 2000-05-22 2008-07-08 Nds Limited Dynamically shifting control word
US20020142757A1 (en) * 2001-03-28 2002-10-03 Leung Nikolai K.N. Method and apparatus for broadcast signaling in a wireless communication system
US20020141371A1 (en) * 2001-03-28 2002-10-03 Hsu Raymond T. Method and apparatus for transmission framing in a wireless communication system
US20020141591A1 (en) * 2001-03-28 2002-10-03 Philip Hawkes Method and apparatus for security in a data processing system
US20110045864A1 (en) * 2001-03-28 2011-02-24 Qualcomm Incorporated Power control for point-to-multipoint services provided in communication systems
US8077679B2 (en) 2001-03-28 2011-12-13 Qualcomm Incorporated Method and apparatus for providing protocol options in a wireless communication system
US7693508B2 (en) 2001-03-28 2010-04-06 Qualcomm Incorporated Method and apparatus for broadcast signaling in a wireless communication system
US20020141365A1 (en) * 2001-03-28 2002-10-03 Leung Nikolai K.N. Method and apparatus for providing protocol options in a wireless communication system
US9100457B2 (en) 2001-03-28 2015-08-04 Qualcomm Incorporated Method and apparatus for transmission framing in a wireless communication system
US20020186846A1 (en) * 2001-06-08 2002-12-12 Nokia Corporation Method for ensuring data transmission security, communication system and communication device
US7995760B2 (en) * 2001-06-08 2011-08-09 Nokia Corporation Method for ensuring data transmission security, communication system and communication device
US20070116282A1 (en) * 2001-08-20 2007-05-24 Qualcomm, Inc. Method and apparatus for security in a data processing system
US20040120527A1 (en) * 2001-08-20 2004-06-24 Hawkes Philip Michael Method and apparatus for security in a data processing system
US20100142432A1 (en) * 2001-10-03 2010-06-10 Qualcomm Incorporated Method and Apparatus For Data Packet Transport In a Wireless Communication System Using an Internet Protocol
US20080226073A1 (en) * 2001-10-09 2008-09-18 Qualcomm Incorporated Method and apparatus for security in a data processing system
US8983065B2 (en) 2001-10-09 2015-03-17 Qualcomm Incorporated Method and apparatus for security in a data processing system
US8713400B2 (en) 2001-10-12 2014-04-29 Qualcomm Incorporated Method and system for reduction of decoding complexity in a communication system
US20100272124A1 (en) * 2001-10-12 2010-10-28 Qualcomm Incorporated Method and system for reduction of decoding complexity in a communication system
US8730999B2 (en) 2001-10-12 2014-05-20 Qualcomm Incorporated Method and system for reduction of decoding complexity in a communication system
US8121292B2 (en) * 2002-02-26 2012-02-21 Qualcomm Incorporated Method and apparatus for scrambling information bits on a channel in a communications system
US20030161471A1 (en) * 2002-02-26 2003-08-28 Yu-Cheun Jou Method and apparatus for scrambling information bits on a channel in a communications system
US7158058B1 (en) 2002-12-09 2007-01-02 Marvell International Ltd. Method and apparatus for generating a seed set in a data dependent seed selector
US7808404B1 (en) 2002-12-09 2010-10-05 Marvell International Ltd. Method and apparatus for generating a seed set in a data dependent seed selector
US20040123123A1 (en) * 2002-12-18 2004-06-24 Buer Mark L. Methods and apparatus for accessing security association information in a cryptography accelerator
US7191341B2 (en) 2002-12-18 2007-03-13 Broadcom Corporation Methods and apparatus for ordering data in a cryptography accelerator
US7568110B2 (en) 2002-12-18 2009-07-28 Broadcom Corporation Cryptography accelerator interface decoupling from cryptography processing cores
US7434043B2 (en) 2002-12-18 2008-10-07 Broadcom Corporation Cryptography accelerator data routing unit
US20040123119A1 (en) * 2002-12-18 2004-06-24 Broadcom Corporation Cryptography accelerator interface decoupling from cryptography processing cores
US20040123120A1 (en) * 2002-12-18 2004-06-24 Broadcom Corporation Cryptography accelerator input interface data handling
US20100048206A1 (en) * 2003-01-02 2010-02-25 Qualcomm Incorporated Method and apparatus for broadcast services in a communication system
US8971790B2 (en) 2003-01-02 2015-03-03 Qualcomm Incorporated Method and apparatus for broadcast services in a communication system
US7346160B2 (en) 2003-04-23 2008-03-18 Michaelsen David L Randomization-based encryption apparatus and method
US20050002531A1 (en) * 2003-04-23 2005-01-06 Michaelsen David L. Randomization-based encryption apparatus and method
US8098818B2 (en) 2003-07-07 2012-01-17 Qualcomm Incorporated Secure registration for a multicast-broadcast-multimedia system (MBMS)
US20050008159A1 (en) * 2003-07-07 2005-01-13 Francesco Grilli Secure registration for a multicast-broadcast-multimedia system (MBMS)
AU2004300912B2 (en) * 2003-07-08 2010-07-22 Qualcomm, Incorporated Method and apparatus for security in a data processing system
US8718279B2 (en) 2003-07-08 2014-05-06 Qualcomm Incorporated Apparatus and method for a secure broadcast system
US20050010774A1 (en) * 2003-07-08 2005-01-13 Rose Gregory Gordon Apparatus and method for a secure broadcast system
WO2005006643A1 (en) * 2003-07-08 2005-01-20 Qualcomm, Incorporated Method and apparatus for security in a data processing system
US20050138379A1 (en) * 2003-09-02 2005-06-23 James Semple Method and apparatus for providing authenticated challenges for broadcast-multicast communications in a communication system
US8724803B2 (en) 2003-09-02 2014-05-13 Qualcomm Incorporated Method and apparatus for providing authenticated challenges for broadcast-multicast communications in a communication system
US8396216B2 (en) 2003-11-21 2013-03-12 Howard G. Pinder Partial dual-encryption using program map tables
US20090147954A1 (en) * 2003-11-21 2009-06-11 Howard Pinder Partial Dual-Encryption Using Program Map Tables
US9264426B2 (en) 2004-12-20 2016-02-16 Broadcom Corporation System and method for authentication via a proximate device
US20060136717A1 (en) * 2004-12-20 2006-06-22 Mark Buer System and method for authentication via a proximate device
US8295484B2 (en) 2004-12-21 2012-10-23 Broadcom Corporation System and method for securing data from a remote input device
US9288192B2 (en) 2004-12-21 2016-03-15 Broadcom Corporation System and method for securing data from a remote input device
US20060133604A1 (en) * 2004-12-21 2006-06-22 Mark Buer System and method for securing data from a remote input device
US20120063597A1 (en) * 2010-09-15 2012-03-15 Uponus Technologies, Llc. Apparatus and associated methodology for managing content control keys

Similar Documents

Publication Publication Date Title
US7130425B2 (en) Method and apparatus for providing a bus-encrypted copy protection key to an unsecured bus
US6005943A (en) Electronic identifiers for network terminal devices
EP0155762B1 (en) Descrambler subscriber key production system utilizing key seeds stored in descrambler
CA2318936C (en) Method for protecting the audio/visual data across the nrss interface
US6115821A (en) Conditional access system, display of authorization status
AU754015B2 (en) Method and apparatus for recording of encrypted digital data
JP3020603B2 (en) Subscription television system using the card - a memory which includes a decoder
US7565546B2 (en) System, method and apparatus for secure digital content transmission
AU693957B2 (en) Method and apparatus for incremental delivery of access rights
US7577846B2 (en) Mechanism of matching between a receiver and a security module
EP0754390B1 (en) Method and apparatus for transmitting and receiving encrypted signals
US6904522B1 (en) Method and apparatus for secure communication of information between a plurality of digital audiovisual devices
CA1331790C (en) Reproduction of secure keys by using distributed key generation data
US7363276B2 (en) Broadcast receiving method and apparatus and information distributing method and apparatus
JP4818559B2 (en) A method of operating a conditional access system to the broadcasting field
EP0506435B1 (en) Independent external security module for a digitally upgradeable television signal decoder
US7702904B2 (en) Key management system and multicast delivery system using the same
US4995080A (en) Television signal scrambling system and method
US7797552B2 (en) Method and apparatus for controlling paired operation of a conditional access module and an integrated receiver and decoder
US4739510A (en) Direct broadcast satellite signal transmission system
US5517567A (en) Key distribution system
CA2049310C (en) External security module for a television signal decoder
EP0314203B1 (en) System for enabling descrambling on a selective-subscription basis in a subscriber communication network
US4389671A (en) Digitally-controlled analog encrypton
JP2584570B2 (en) Encrypted information system for a receiver

Legal Events

Date Code Title Description
FPAY Fee payment

Year of fee payment: 8

AS Assignment

Owner name: COMSAT CORPORATION, MARYLAND

Free format text: CHANGE OF NAME;ASSIGNOR:COMMUNICATIONS SATELLITE CORPORATION;REEL/FRAME:006711/0455

Effective date: 19930524

FPAY Fee payment

Year of fee payment: 12