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VideoCipher is a brand name of analog scrambling and de-scrambling equipment for cable and satellite television invented primarily to keep consumer Television receive-only (TVRO) satellite equipment from receiving TV programing except on a subscription basis. It was invented in 1983 by Linkabit Corporation, which was bought out by M/A-COM in 1985 and operated as M/A-COM Linkabit. In the late 1980's, M/A-COM began divesting divisions which fell outside their core RF & Microwave component and subsystem products. The Linkabit division was acquired 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 and digital cable transmission, Videocipher began to fade from existence, and was officially fully retired on December 31, 2008. As of June 23, 2013 there is just one channel still using Videocipher II, though it cannot be subscribed to by the general public.
There are several variants of the Videocipher scrambling system:
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-1990s 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 was discontinued in the early 2000s.
Videocipher I (VCI) system was initially considered for use by HBO in the 1980s. HBO tested VCI extensively, but was ultimately rejected in favor of Videocipher II. HBO use of VCI would have required descramblers for home satellite viewers. Thus VCI was determined to be too expensive for consumer use.
PBS in the USA used VideoCipher I on its satellite feeds to its member stations in the mid-80s to take advantage of the high-fidelity digital audio capability offered by VCI. This would be desirable for some of the programming PBS would air in that era, such as classical concerts and other musical programming, some of which were simulcast by partnering public radio stations using the same audio feed. PBS had attempted in 1979 to send its program audio digitally to its member stations using a system called DATE (Digital Audio for TElevision), which used the existing analog video's vertical blanking interval (VBI) to send digital audio. VCI provided this same feature while freeing up the VBI for other purposes like closed-captioning and teletext, making DATE obsolete by the mid-1980s (however, DATE did offer 4 channels of audio as opposed to VideoCipher's 2-channel stereo).
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).
This was the first consumer TVRO 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 sister channel Cinemax, 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 premium channels like HBO.
A company called Magna Systems would fax monthly keys to satellite dealers and the dealers would distribute 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.
In 1992, following years of security breaches with the Videocipher II system, the Videocipher II Plus became standard. In 1993, some VCII programming was phased out, espically for Movie channels and PPV, but many networks and Sports CH. now Fox sports remained on the VC II stream. The new system was 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.
General Instrument discontinued production of VC II+ RS modules in 1998 in favor of its DigiCipher system. Over the next ten years, broadcasters migrated to digital transmission delivery and discontinued their analog feeds. In October 2008, it was announced by Motorola that their authorization center would no longer authorize any new decoders after December 31, 2008, and that the current remaining analog Videocipher channels would switch entirely to digital transmission after that same date.
- The Museum of Broadcast Communications, SCRAMBLED SIGNALS
- "Hot DATE for PBS", American Libraries 10 (7), July 1979: 439–440