VideoGuard produced by NDS
NDS Group
NDS Group Plc. is a developer of pay TV technology. NDS was established in 1988 as an Israeli start up company. It was acquired by News Corporation in 1992. The company is currently headquartered in Staines, United Kingdom...

, is a digital 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...

 system for use with conditional access
Conditional access
Conditional Access is the protection of content by requiring certain criteria to be met before granting access to this content...

 television broadcasting. It is used on 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...

 systems - some of which are operated by News Corporation
News Corporation
News Corporation or News Corp. is an American multinational media conglomerate. It is the world's second-largest media conglomerate as of 2011 in terms of revenue, and the world's third largest in entertainment as of 2009, although the BBC remains the world's largest broadcaster...

, which owns about half (49%) of NDS. Its two most widely used implementations are BSkyB's Sky Digital in the United Kingdom
United Kingdom
The United Kingdom of Great Britain and Northern IrelandIn the United Kingdom and Dependencies, other languages have been officially recognised as legitimate autochthonous languages under the European Charter for Regional or Minority Languages...

 and Ireland
Republic of Ireland
Ireland , described as the Republic of Ireland , is a sovereign state in Europe occupying approximately five-sixths of the island of the same name. Its capital is Dublin. Ireland, which had a population of 4.58 million in 2011, is a constitutional republic governed as a parliamentary democracy,...

 and DirecTV
DirecTV is an American direct broadcast satellite service provider and broadcaster based in El Segundo, California. Its satellite service, launched on June 17, 1994, transmits digital satellite television and audio to households in the United States, Latin America, and the Anglophone Caribbean. ...

 in the United States
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...

, the former of which launched the digital version of the system in 1998. Several other broadcasters around the world use the VideoGuard system, including Hot (Israel)
Hot (Israel)
HOT Telecommunication Systems Ltd. is a company that provides cable television, last-mile Internet access, broadband and telecommunication services in Israel. It also provides various data transmission services and network services at different rates, services to the business sector and other...

, Yes (Israel), Viasat
Viasat is a DBS distributor and TV broadcaster, owned by the Swedish media conglomerate Modern Times Group. Broadcasting from London, the target markets are in the Nordic and the Baltic Countries...

 (Scandinavia), SKY Italia
Sky Italia
Sky Italia S.r.l. is an Italian digital satellite television platform owned by News Corporation launched on 1 August 2003, when the former platforms TELE+ and Stream TV merged together...

 (Italy), Sky Brazil (Brazil), Sky Network Television
SKY Network Television
Sky Network Television Limited , , is a New Zealand pay television service. On 30 June 2011, Sky had 829,421 subscribers, which comprises:*808,617 digital subscribers*20,840 other subscribers...

 (New Zealand), Foxtel
Foxtel is an Australian pay television company, operating cable, direct broadcast satellite television and IPTV services. It was formed in 1995 through a joint venture established between Telstra and News Corporation....

 (Australia), Airtel DigitalTV (India), Tata Sky
Tata Sky
TATA Sky is a direct broadcast satellite television provider in India, using MPEG-2 digital compression technology, transmitting using INSAT 4A at 83.0°E....

 & Hathway
Hathway Cable & Datacom Ltd is a major cable television service operator in India that is based in Mumbai. It has large operations in many cities, including Hyderabad, Mumbai, Pune and Bangalore. It has diversified into providing internet via cable and was one of the first to do so in Chennai. In...

DVB-C stands for Digital Video Broadcasting - Cable and it is the DVB European consortium standard for the broadcast transmission of digital television over cable...

) (India), Astro (Malaysia), D Smart (Turkey), TotalTV
TotalTV is the first Serbian Direct To Home platform, offering over 80 digital TV channels via satellite. Owner of platform is the largest Serbian cable operator Serbia Broadband - Srpske kablovske mreže ....

 (Balkan), ONO (Spain)
ONO (Spain)
ONO is a Spanish broadband communication and entertainment company, delivering integrated telephone, television and Internet services to its residential customers. In this segment, it has 3.7 million services contracted and over six million users....

, Canadian Broadcasting Corporation
Canadian Broadcasting Corporation
The Canadian Broadcasting Corporation, commonly known as CBC and officially as CBC/Radio-Canada, is a Canadian crown corporation that serves as the national public radio and television broadcaster...

 (Canada), China Central Television
China Central Television
China Central Television or Chinese Central Television, commonly abbreviated as CCTV, is the major state television broadcaster in mainland China. CCTV has a network of 19 channels broadcasting different programmes and is accessible to more than one billion viewers...

 (China), Serbia BroadBand
Serbia Broadband
SBB is the leading cable TV and broadband Internet provider in Serbia.Ownership structure:* Mid Europa Partners...

 (Serbia), Telewizja Polska
Telewizja Polska
Telewizja Polska Spółka Akcyjna is Poland's public broadcasting corporation...

 (Poland) and KabelBW (Germany), Vivacom (Bulgaria), STAR TV
Satellite Television Asia Region is an Asian TV service owned by Rupert Murdoch's News Corporation. It is headquartered in Hong Kong, with regional offices in mainland China, Taiwan....

/Fox International Channels
Fox International Channels
Fox International Channels is a subsidiary of the Fox Entertainment Group, which is a part of Rupert Murdoch's global media conglomerate News Corporation...

 (Asia), Cignal Digital TV
Cignal Digital TV
Cignal Digital TV is a subscription-based Direct-To-Home satellite television service provider in the Philippines. Cignal is owned by MediaScape, a wholly owned subsidiary of the MediaQuest Holdings, Inc...

 (Philippines), Aora TV
Aora TV
Aora TV is an Indonesian direct broadcast satellite pay television company that is operated by PT Karya Megah Adijaya and is owned by Rini M. Soemarno, Ongki P. Soemarno and join at dormant period Sugiono Wiyono. It started its nation-wide broadcast in the beginning of August 2008 with an initial...

 (Indonesia), Telecom Italia
Telecom Italia
Telecom Italia is the largest Italian telecommunications company, also active in the media and manufacturing industries. Now a private concern listed on the Borsa Italiana, it was founded in 1994 by the merger of several state-owned telecommunications companies, the most important of which was...

 (Italy), OTAU TV (Kazakhstan), OTE TV
OTE TV is a the corporate name for two Pay television services in Greece, owned by Greek Telcom operator OTE. The two services are as follows:* OTE TV via Conn-x - IPTV service* OTE TV via Satellite - satellite television service...


Since the majority of content provided by companies like BSkyB requires subscription, VideoGuard protects that content by encrypting both standard subscription channels and pay-per-view
Pay-per-view provides a service by which a television audience can purchase events to view via private telecast. The broadcaster shows the event at the same time to everyone ordering it...

 movies and events. Access flags can be downloaded to the subscriber's card either over the air (via 'hidden' data streams) or by using the box's built in modem
A modem is a device that modulates an analog carrier signal to encode digital information, and also demodulates such a carrier signal to decode the transmitted information. The goal is to produce a signal that can be transmitted easily and decoded to reproduce the original digital data...

, thereby allowing rapid changing of channel packages and ordering of events.

Already in use in America since 1997, the VideoGuard system was introduced to the UK by NDS in 1998 with the launch of Sky Digital, replacing the VideoCrypt
VideoCrypt is a cryptographic, smartcard-based conditional access television encryption system that scrambles analogue pay-TV signals. It was introduced in 1989 by News Datacom and was used initially by Sky TV and subsequently by several other broadcasters on the SES Astra satellites at 19.2°...

 system (also supplied by NDS) in use on Sky's analogue broadcasts. To date, despite widespread piracy of the US DirecTV service between 1997 and 2002, the implementation in the UK has remained secure, although various pay per view flaws have been identified in the past. Even these flaws are related merely to the circuitry of the Set-Top Box (STB), rather than the NDS card. It is suspected that the version initially used by Sky Digital was either insecure or close to being broken, as a software update rolled out to all boxes required replacement of the BSkyB subscriber's viewing card. Even so, wholesale card replacements are rare, currently having occurred just twice during the lieftime of Sky Digital - once in 2002/2003, and again in 2009 (replacements carried out between April and June).

While most commonly used to protect pay-TV, VideoGuard is also used by numerous non-subscription broadcasters to enforce geographic rights restrictions. Videoguard has been used by the BBC, ITV, and Channel 4 to restrict non-UK viewing, although in recent years these broadcasters have moved to broadcasting FTA on the more geographically restricted footprint of the Astra 2D
Astra 2D
Astra 2D is one of a group of Astra communications satellites operated by SES, located at 28.2° east in the Clarke Belt. It is a Hughes HS-376 craft, and was launched from the Guiana Space Centre in December 2000....

 satellite which is mainly, although not entirely, focused on the UK and Ireland. In some cases, encryption is still used on some versions of ITV and Channel 4 services where rights issues or a lack of capacity on the Astra 2D satellite are an issue.

A further example is British television channel Five and its spin off channels (Five US, Fiver and the +1 versions) which still use this 'Free To View' encryption mode to prevent these channels being viewed outside the UK for copyright reasons. Five has also made a single free-to-air version of its primary channel available in Free-to-Air format via Astra 2D. This feed sometimes carries an apology caption to black out programming where rights issues remain.

Many broadcasters choose to pair their cards, meaning that a paired (also called "married") card can be used only in a specific broadcaster-supplied STB, or by using the serial number from said receiver with one of the reverse-engineered solutions. In the case of Sky Digital, all cards are married to a particular set top box, although almost all non-premium channels will still allow viewing even if the box and card are not paired. Other channels, such as Sky's sports and movie channels, cannot be viewed unless the viewing card is being used in its specifically paired set top box.

Reverse Engineering

Videoguard is unusual in that legitimate external Conditional Access Modules are not available, the encryption system instead being built in to the hardware and firmware of platform-supplied set top boxes. However, several groups have managed to reverse-engineer VideoGuard to the point where a legitimate subscriber's card can be utilised in third-party receivers to decrypt those channels which that subscriber is authorised to view. A software CAM emulator exists for the Dreambox
The Dreambox is a series of Linux-powered DVB satellite, terrestrial and cable digital television receivers , produced by German multimedia vendor Dream Multimedia.- History and Description :...

 & Triple-Dragon Linux
Linux is a Unix-like computer operating system assembled under the model of free and open source software development and distribution. The defining component of any Linux system is the Linux kernel, an operating system kernel first released October 5, 1991 by Linus Torvalds...

-powered satellite receivers, along with the Diablo, Dragon, Giga-Blue and T-Rex Conditional Access modules. Some of the reverse-engineered solutions are unable to update the card, meaning the legitimate card needs to be returned to official Sky receiver for a few hours (or overnight) to be refreshed, or programmes will no longer decrypt. An example of a reverse-engineered solution that does support card updates is NDSCam.

Sky Digital 2009 card replacements

As of late March 2009, BSkyB have begun issuing replacement NDS smartcards. These new cards are believed to close off the current software CAM loophole.

External links

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