Videocipher
From Wikipedia, the free encyclopedia
VideoCipher is a brand name of analog scrambling equipment for satellite television invented in 1983 by Linkabit systems, which was bought out by MA/COM in 1985. MA/COM was finally bought out by General Instrument in 1987. Currently, Videocipher technology is controlled by Motorola Corporation. Videocipher scrambling usually involves the DES encryption scheme. With the shift to digital satellite transmission, the Videocipher system will possibly be phased out entirely by the end of this decade.
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[edit] Variants
There are several variants of the Videocipher scrambling system:
[edit] Videocipher I
This was the first version of the Videocipher system that was first demonstrated by Linkabit in 1983.
Also known as Videocipher IB, this variation on Videocipher was commonly used by sports backhauls. CBS used this system from 1987 to the mid-1990's to encrypt its transmissions to affiliates on the Telstar 301 and Telstar 302 satellites. In Canada, the CTV television network also used this technology on its network feeds. With this system the video is scrambled by means of re-ordering the video scan lines, while all audio remains in the clear. This system has been discontinued in recent years.
This system was initially considered for use by HBO in the 1980's, but was rejected in favor of Videocipher II as it was determined that descramblers for home satellite viewers would be required, and the Videocipher I was determined to be too expensive for consumer use.
The Leitch Viewguard scrambling system used for satellite feeds as well used the same video line re-ordering as well, while also leaving the audio intact. ABC and Fox used Viewguard as well on their analog network feeds to their affiliate stations shortly before switching to digital satellite distribution in 2005 (for ABC) and 2004 (for Fox).
[edit] Videocipher II
This was the first consumer scrambling system. It began testing in 1985 on HBO satellite transponders on Satcom 3R and Galaxy 1 and entered full use in January 1986 by HBO, and within two years was used by a majority of major cable television programmers. However, lapses in its security enabled some cable pirates to modify the descrambler to receive free programming. Beginning in 1991, programmers began to phase out the VCII system in favor of the highly secure Videocipher II Plus (RS) system. The system was fully phased out in 1993. Originally sold as a stand-alone decoder box that consisted of a fully electronic decoder and the actual descrambler module, some satellite system manufacturers began to manufacturer their receivers with the module installed. This system works by encrypting both audio (in digital sound) and video. A Videocipher II decoder is still capable of decoding only the video portion of a Videocipher II Plus.
Furthermore, in the late eighties and early nineties, VideoCipher II modules that had been pirated, began to receive constant Electronic Counter Measures (ECM) "Keys" which would roll over every month. Later on, keys began to roll constantly for pay per view channels and HBO.
A company called Magna Systems would fax monthly keys to satellite dealers and the dealers would distriubute the keys to their customers. Magna Systems warned that programmers would begin rolling keys every few days.
In response to the increasing frequency of key changes, enterprising pirates devised more efficient means of delivering the new keys to the hacked boxes. Among these contraptions included "VMS" modems which when added to the Videocipher module allowed them to dial into a bulletin board system and download the updated keys.
After HBO left the VideoCipher II datastream in favor of the more secure VideoCipher II Plus (RS) datastream, other programmers followed suit. Having a VideoCipher II module was no longer worth anything unless the viewer wanted to watch adult/XXX programming with no audio.
Some viewers who had both cable and satellite found a way to marry audio and video. Viewers found a way to get audio from a cable line and video from satellite with their VideoCipher II and push both to their VCRs and TVs.
Due to the advanced VideoCipher II Plus datastream, video may appear to "flicker" or struggle on an old VideoCipher II module. If the module has a newer pirate chip installed, flickering may or may not be a problem.
[edit] Videocipher II+/RS
In 1992, following years of security breaches with the Videocipher II system, the Videocipher II Plus became standard. In 1993, all VCII programming was phased out. This is a higher-security system with two variants. The Videocipher-RS system (RS for Renewable Security) is the Videocipher II Plus system with a slot in the back of the decoder module to where a card could be inserted to upgrade the security if the VCII Plus system were ever breached.
[edit] Technological Obsolesence
General Instrument discontinued production of VC II+ RS modules in 1998 in favor of its DigiCipher system.
- Some C-band satellite programmers still use this system for their programming, however most broadcasters are in the process of phasing this out for digital delivery.
- With the shift to digital delivery, the Videocipher system overall will most likely be phased out by 2010.
