DigiCipher 2
Encyclopedia
DigiCipher 2, or simply DCII, is a proprietary standard format of digital signal transmission and encryption
with MPEG-2 signal video compression used on many communications satellite
television
and audio signals. The DCII standard was originally developed in 1997 by General Instrument
, which is now the Home and Network Mobility division of Motorola
.
The original attempt for a North America
n digital signal encryption and compression standard was DigiCipher 1, which was used most notably in the now-defunct PrimeStar
medium-power direct broadcast satellite
(DBS) system during the early 1990s. The DCII standard predates wide acceptance of DVB-based digital terrestrial television compression (although not cable or satellite DVB) and therefore is incompatible with the DVB standard.
The primary difference between DigiCipher 2 and DVB lies in how each standard handles SI, or System Information. DigiCipher 2 also relies on the fact that its signals must be understood in terms of a virtual channel number in addition to the DCII signal's downlink frequency, whereas DVB signals have no virtual channel number.
Approximately 70% of newer first-generation digital cable
networks in North America use the 4DTV
/DigiCipher 2 format. The use of DCII is most prevalent in North American digital cable television
set top boxes. DCII is also used on Motorola's 4DTV digital satellite television
tuner and Shaw Direct's DBS receiver.
Encryption
In cryptography, encryption is the process of transforming information using an algorithm to make it unreadable to anyone except those possessing special knowledge, usually referred to as a key. The result of the process is encrypted information...
with MPEG-2 signal video compression used on many communications satellite
Communications satellite
A communications satellite is an artificial satellite stationed in space for the purpose of telecommunications...
television
Television
Television is a telecommunication medium for transmitting and receiving moving images that can be monochrome or colored, with accompanying sound...
and audio signals. The DCII standard was originally developed in 1997 by General Instrument
General Instrument
General Instrument was an electronics manufacturer based in Horsham, PA specializing in semiconductors and cable television equipment. The company was active until 1997, when it split into which was later acquired by Vishay Intertechnology in 2001, CommScope and NextLevel Systems General...
, which is now the Home and Network Mobility division of Motorola
Motorola
Motorola, Inc. was an American multinational telecommunications company based in Schaumburg, Illinois, which was eventually divided into two independent public companies, Motorola Mobility and Motorola Solutions on January 4, 2011, after losing $4.3 billion from 2007 to 2009...
.
The original attempt for a North America
North America
North America is a continent wholly within the Northern Hemisphere and almost wholly within the Western Hemisphere. It is also considered a northern subcontinent of the Americas...
n digital signal encryption and compression standard was DigiCipher 1, which was used most notably in the now-defunct PrimeStar
PrimeStar
PrimeStar was a U.S. direct broadcast satellite broadcasting company formed in 1991 by a consortium of cable television system operators. PrimeStar was the first medium-powered DBS system in the United States but slowly declined in popularity with the arrival of DirecTV in 1994 and Dish Network in...
medium-power direct broadcast satellite
Direct broadcast satellite
Direct broadcast satellite is a term used to refer to satellite television broadcasts intended for home reception.A designation broader than DBS would be direct-to-home signals, or DTH. This has initially distinguished the transmissions directly intended for home viewers from cable television...
(DBS) system during the early 1990s. The DCII standard predates wide acceptance of DVB-based digital terrestrial television compression (although not cable or satellite DVB) and therefore is incompatible with the DVB standard.
The primary difference between DigiCipher 2 and DVB lies in how each standard handles SI, or System Information. DigiCipher 2 also relies on the fact that its signals must be understood in terms of a virtual channel number in addition to the DCII signal's downlink frequency, whereas DVB signals have no virtual channel number.
Approximately 70% of newer first-generation digital cable
Digital cable
Digital cable is a generic term for any type of cable television distribution using digital video compression or distribution. The technology was originally developed by Motorola.-Background:...
networks in North America use the 4DTV
4DTV
4DTV is the name of a Television receive-only consumer satellite television tuner technology manufactured by Motorola for use with large-diameter parabolic satellite dish antennas on the C and Ku frequency bands on multiple satellites...
/DigiCipher 2 format. The use of DCII is most prevalent in North American digital cable television
Cable television
Cable television is a system of providing television programs to consumers via radio frequency signals transmitted to televisions through coaxial cables or digital light pulses through fixed optical fibers located on the subscriber's property, much like the over-the-air method used in traditional...
set top boxes. DCII is also used on Motorola's 4DTV digital satellite television
Satellite television
Satellite television is television programming delivered by the means of communications satellite and received by an outdoor antenna, usually a parabolic mirror generally referred to as a satellite dish, and as far as household usage is concerned, a satellite receiver either in the form of an...
tuner and Shaw Direct's DBS receiver.