XPost: comp.dsp, sci.crypt, sci.electronics.design
From: OneBigLever@InfiniteSeries.Org
On Fri, 18 Dec 2009 09:36:52 -0500, PeterD wrote:
>On Thu, 17 Dec 2009 17:44:12 -0800 (PST), Mark
>wrote:
>
>>
>>>
>>> Passing encrypted video over a satellite network built for unencrypted
>>> analog video is not a trivial challenge. As far as I know, there
>>> exists no scheme to do this that has not been broken already. The
>>> problem is that encryption works partly by diffusing information so
>>> that no part of the output looks like any part of the input. The
>>> satellite link is filled with errors and distortion that have to be
>>> contained to retain adequate video quality.
>>>
>>> DS
>>
>>um,, is that why General Instrument was able to do it did it 15 years
>>ago for HBO?
>>
>>Mark
>>
>
>They didn't do the video, just the audio. Video was a very simple
>inversion technique, that was trivial to break. The audio was DES (so
>they said) encrypted, but there were several holes in the system that
>rendered it a bit less secure.
You absolutely have no clue what was done or how or why. GI encrypted
the entire 6MHz wide video signal, you dope. Maybe you are thinking of
"OnTV". That was in-band gated synch scrambling and the audio was not
digitized OR encrypted... it was simply shifted and not processed by the
tuner unless the gate is shifted back where it belongs.
Here... ALL of these were around and failed as well.
Older television encryption systems
* Oak Industries
Oak Orion was originally used for analog satellite television pay channel
access in Canada. Was innovative for its time as it used digital audio.
It has been completely replaced by digital encryption technologies. Was
used by Sky Channel in Europe between the years 1982 and 1987. Oak
developed related encryption systems for cable TV and broadcast pay TV
services such as ON TV. The Oak systems used a sine wave added to the
video signal to interfere with the video sync and relocated audio to a
sub-carrier.
* Leitch Technology
Leitch Viewguard is an analog encryption standard used primarily by
broadcast TV networks in the North America. Its method of scrambling is
by re-ordering the lines of video (Line Shuffle), but leaves the audio
intact and listenable. Terrestrial broadcast CATV systems in Northern
Canada used this conditional access system for many years. It is only
occasionally used today on some satellite circuits because of its
similarity to D2-MAC and B-MAC.
* B-MAC
B-MAC has not been used for DTH applications since Primestar switched to
an all-digital delivery system in the mid-1990s.
* VideoCrypt
Analogue cut and rotate scrambling system with smartcard based
conditional access system, used in 1990s by several European satellite
broadcasters, mainly British Sky Broadcasting. Was also used by Sky New
Zealand (Sky-NZ). One version of Videocrypt (VideoCrypt-S) had the
capability of scrambling sound. A soft encryption option was also
possible where the encrypted video could be transmitted with a fixed key
and any VideoCrypt decoder could decode it.
* RITC Discret 1
System based on horizontal line delay and audio scrambling. Each line of
video was pseudorandomly delayed by either 0 nS, 902 nS or 1804 nS. (Line
Delay) First used in 1984 by French channel Canal Plus, it was widely
compromised after the December 1984 issue of "Radio Plans" magazine
printed decoder plans.
* SATPAC
Used by European channel FilmNet the SATPAC system interfered with the
horizontal and vertical synchronization signals and transmitted a signal
containing synchronization and authorization data on a separate
subcarrier. The system was first used in September 1986 and saw many
upgrades as it was easily compromised by pirates. By September 1992,
FilmNet changed to D2-MAC EuroCrypt.
* Telease MAAST / Sat-Tel SAVE
Added an interfering sine wave of a frequency (circa 93.750 kHz) to the
video signal. This interfering signal was approximately six times the
frequency of the horizontal refresh. It had an optional sound scrambling
using Spectrum Inversion. Used in the UK by BBC for its world service
broadcasts and by the now defunct UK movie channel "Premiere".
* Payview III
Used by German/Swiss channel Teleclub in the early 1990s, this system
employed various methods such as video inversion, modification of
synchronization signals and a pseudo line delay effect.
* D2-MAC EuroCrypt
Conditional Access system using the D2-MAC standard. Developed mainly by
France Telecom, the system was smartcard based. The encryption algorithm
in the smartcard was based on DES. It was one of the first smart card
based systems to be compromised.
* Nagravision analog system
An older Nagravision system for scrambling analog satellite and
terrestrial television programs was used in the 1990s, for example by the
German pay-TV broadcaster Premiere. In this line-shuffling system, 32
lines of the PAL TV signal are temporarily stored in both the encoder and
decoder, and read out in permuted order under the control of a
pseudorandom number generator. A smartcard security microcontroller (in a
key-shaped package) decrypts data that is transmitted during the blanking
intervals of the TV signal and extracts the random seed value needed for
controlling the random number generation. The system also permitted the
audio signal to be scrambled by inverting its spectrum at 12.5 kHz using
a frequency mixer.
--- SoupGate-Win32 v1.05
* Origin: you cannot sedate... all the things you hate (1:229/2)
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