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Videocipher

Videochiper is a brand name of analog scrambling equipment for satellite television invented in the early 1980's 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 Corpiration. 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.

Contents

Variants

There are several variants of the Videocipher scrambling system:

Videocipher I

Also known as Videocipher IB, this variation on Videocipher was commonly used by sports backhauls. CBS also used this system from 1987 to the mid-1990's to encrypt its transmissions to affiliates on the Telstar 301 and Telstar 302 satellites. This system has been discontinued in recent years. With this system, the video is scrambled most of the time with audio in the clear.

Videocipher II

This was the first consumer scrambling system. It entered 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 recieve free programming. Beginning in 1991, programmers began to phase out the VCII system in favor of the highly secure Videocipher II Plus 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 recievers 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.

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. General Instrument discontinued production of these 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 within the next five years.


10-26-2009 08:16:03
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