Common Interface
Encyclopedia
All Common Interface equipment must comply with the EN 50221-1997 standard. This is a defined standard that enables the addition of a conditional access module
Conditional access module
A conditional access module is an electronic device, usually incorporating a slot for a smart card, which equips an Integrated Digital Television or set-top box with the appropriate hardware facility to view conditional access content that has been encrypted using a conditional access system...
(CAM) in a DTV Receiver
DTV Receiver
A DTV receiver is a set-top box that permits the reception of Digital television. Its components are very similar to a desktop PC. The DTV receiver is a vital link in the chain of television system...
, to adapt it to different kinds of cryptography
Cryptography
Cryptography is the practice and study of techniques for secure communication in the presence of third parties...
. Indeed, one of Digital Video Broadcasting's main strengths is the option of implementing the required conditional access capability on the Common Interface.
This allows broadcasters to use modules containing solutions from different suppliers in the same broadcast system, thus increasing their choice and anti-piracy options.
The interconnect is formed between a host and a module. Examples of a host are a digital television
Digital television
Digital television is the transmission of audio and video by digital signals, in contrast to the analog signals used by analog TV...
or digital set-top box
Set-top box
A set-top box or set-top unit is an information appliance device that generally contains a tuner and connects to a television set and an external source of signal, turning the signal into content which is then displayed on the television screen or other display device.-History:Before the...
. The EN 50221 specification allows many types of module but only the Conditional Access Module
Conditional access module
A conditional access module is an electronic device, usually incorporating a slot for a smart card, which equips an Integrated Digital Television or set-top box with the appropriate hardware facility to view conditional access content that has been encrypted using a conditional access system...
(CAM) has found popularity because of the Pay TV
Pay TV
Pay television, premium television, or premium channels refers to subscription-based television services, usually provided by both analog and digital cable and satellite, but also increasingly via digital terrestrial and internet television...
market.
Mode of Operation
A DVB receiver may have one or two slots implementing the Common InterfaceCommon Interface
In Digital Video Broadcasting, the Common Interface is an extensible digital interconnect found in the digital TV market. It is also known as DVB-CI for Digital Video Broadcast Common Interface....
(CI). The CI uses the conditional access module
Conditional access module
A conditional access module is an electronic device, usually incorporating a slot for a smart card, which equips an Integrated Digital Television or set-top box with the appropriate hardware facility to view conditional access content that has been encrypted using a conditional access system...
(PCMCIA) connector and conforms to the Common Scrambling Algorithm
Common Scrambling Algorithm
The Common Scrambling Algorithm is the encryption algorithm used in the DVB digital television broadcasting for encrypting video streams.CSA was specified by ETSI and adopted by the DVB consortium in May 1994.-History:...
(CSA), the normative that specifies that such a receiver must be able to accept DES (Data Encryption Standard
Data Encryption Standard
The Data Encryption Standard is a block cipher that uses shared secret encryption. It was selected by the National Bureau of Standards as an official Federal Information Processing Standard for the United States in 1976 and which has subsequently enjoyed widespread use internationally. It is...
) keys in intervals of some milliseconds, and use them to decode private channels according to a specific algorithm.
Those algorithms are proprietary to individual suppliers. Each one uses their own algorithms and there is no defined standard for them.
As the full MPEG-2
MPEG-2
MPEG-2 is a standard for "the generic coding of moving pictures and associated audio information". It describes a combination of lossy video compression and lossy audio data compression methods which permit storage and transmission of movies using currently available storage media and transmission...
transport data stream comes out of the demodulator, and error correction units, the DTV Receiver
DTV Receiver
A DTV receiver is a set-top box that permits the reception of Digital television. Its components are very similar to a desktop PC. The DTV receiver is a vital link in the chain of television system...
sends it through the card plugged into the Common Interface, before it is processed by the MPEG demultiplexer in the receiver. If several CI cards are present, the MPEG transport data stream will be passed sequentially through all these cards.
An embedded CAM may not physically exist, as it may be in CPU software. In such a case, only the ISO card reader normally in the CAM is fitted and not the PCMCIA type CI slots.
Even if the Common Interface has been created to resolve cryptography issues, it can have other functions using other types of modules such as Web Browser
Web browser
A web browser is a software application for retrieving, presenting, and traversing information resources on the World Wide Web. An information resource is identified by a Uniform Resource Identifier and may be a web page, image, video, or other piece of content...
, iDTV
Integrated Digital Television
An Integrated Digital Television set is a television set with a built in digital tuner, be it for DVB-T, DVB-S, DVB-C, DMB-T/H, ATSC or ISDB. Most of them also allow reception of analogue signals . They do away with the need for a set top box for converting those signals for reception on a...
(Interactive Television
Interactive television
Interactive television describes a number of techniques that allow viewers to interact with television content as they view it.- Definitions :...
), and so forth.
In Europe, DVB-CI is obligatory in all iDTV terminals.
Conditional Access Module (CAM)
The host sends an encrypted MPEG transport stream to the CAM and the CAM sends the decrypted transport stream back to the host. The CAM often contains a smart-card reader.Standards
The normative DVB-CI standard EN 50221 was defined in 1997 by CENELEC, the European Committee for Electrotechnical Standardization.According to the Common Interface scheme:
- host : A device where module(s) can be connected; for example, an Integrated receiver/decoderIntegrated receiver/decoderAn integrated receiver/decoder is an electronic device used to pick-up a radio-frequency signal and convert digital information transmitted in it.-Consumer IRDs:...
(IRD), a VCR, a PC ... - module : A small device, not working by itself, designed to run specialised tasks in association with a host; for example, a conditional access sub system, an electronic program guide application module, or to provide resources required by an application but not provided directly by the host.
The specification only defines two aspects, two logical interfaces to be included on the same physical interface. The first interface is the MPEG-2
MPEG-2
MPEG-2 is a standard for "the generic coding of moving pictures and associated audio information". It describes a combination of lossy video compression and lossy audio data compression methods which permit storage and transmission of movies using currently available storage media and transmission...
Transport Stream. The link and physical layers are defined in this specification and the higher layers are defined in the MPEG-2
MPEG-2
MPEG-2 is a standard for "the generic coding of moving pictures and associated audio information". It describes a combination of lossy video compression and lossy audio data compression methods which permit storage and transmission of movies using currently available storage media and transmission...
specifications. The second interface, the command interface, carries commands between the host (receiver) and the module.
The specification does not define the operation or functionality of a conditional access system application on the module. The applications that may be performed by a module communicating across the interface are not limited to conditional access or to those described in this specification. More than one module may be supported concurrently.
The common interface shares many features of the PC Card
PC Card
In computing, PC Card is the form factor of a peripheral interface designed for laptop computers. The PC Card standard was defined and developed by the Personal Computer Memory Card International Association which itself was created by a number of computer industry companies in the United States...
Standard (PCMCIA). By reducing the widths of the address
and data busses it has been possible to include a bi-directional parallel transport stream interface.
Transport Stream Interface (TSI)
The transport stream format is specified by IEC 13818-1 and is the MPEG 2 TS format.Command Interface
In addition there is a command interface for communication between the host and module.This communication is in the form of a layered protocol stack which allows the host and module to share resources. For example the module can request the current date and time from the host, or can make the host display messages on the TV screen and can then read keypresses from the host remote control. The resource-sharing feature allows the CAM to request and receive PIN numbers as well as allowing the module to implement an interactive TV service.
The Command Interface is extensible and there are several specification documents available which describe these extensions. For example the host could contain a modem for communication over a telephone line allowing the CAM to implement pay-per-view. However these extensions have often not proved popular with manufacturers.
CI+
CI Plus or Common Interface Plus implements a form of copy protection between a Conditional Access ModuleConditional access module
A conditional access module is an electronic device, usually incorporating a slot for a smart card, which equips an Integrated Digital Television or set-top box with the appropriate hardware facility to view conditional access content that has been encrypted using a conditional access system...
(CAM) and the television receiver (display). CI+ is non-compatible update from CIv1. Old television receivers, which have CIv1 CI-slot, can't be used with CI+ CAM.
Definition
CI+ is a specification that extends the Common Interface as found in the digital broadcasting standard. It has been developed by consumer electronic firms Panasonic, PhilipsPhilips
Koninklijke Philips Electronics N.V. , more commonly known as Philips, is a multinational Dutch electronics company....
, Samsung
Samsung Electronics
Samsung Electronics is a South Korean multinational electronics and information technology company headquartered in Samsung Town, Seoul...
and Sony
Sony
, commonly referred to as Sony, is a Japanese multinational conglomerate corporation headquartered in Minato, Tokyo, Japan and the world's fifth largest media conglomerate measured by revenues....
, as well as pay-TV technology company SmarDTV
Kudelski Group
The Kudelski Group claims to be a "world leader in digital security and convergent media solutions" for the delivery of digital and interactive content...
and fabless chip
Integrated circuit
An integrated circuit or monolithic integrated circuit is an electronic circuit manufactured by the patterned diffusion of trace elements into the surface of a thin substrate of semiconductor material...
maker Neotion.
A first draft of the specification was put up for review early in 2008. The final version was released at the end of May 2008.
By making use of certificates and a certification authority, a trusted channel is formed between the CAM and television receiver, when scrambled content is being received. In the original CI standard, decrypted content could be sent over the PCMCIA
PC Card
In computing, PC Card is the form factor of a peripheral interface designed for laptop computers. The PC Card standard was defined and developed by the Personal Computer Memory Card International Association which itself was created by a number of computer industry companies in the United States...
interface unscrambled. The establishment of the Trusted Authority has been completed and an official security certification lab appointed. With the development of CI+, the standard has now come under the umbrella of the DVB standards organisation .
A CI+ compliant device must also implement MHEG-5
MHEG-5
MHEG-5, or ISO/IEC 13522-5, is part of a set of international standards relating to the presentation of multimedia information, standardised by the Multimedia and Hypermedia Experts Group...
(or MHP
MHP
MHP may stand for:*Minsk-1 Airport*Montana Highway Patrol*Monty Hall problem*A mental health professional*Milliyetçi Hareket Partisi - a Turkish nationalist political party*Multimedia Home Platform...
) interactive TV engines to manage navigation of the user within an interactive TV application, using its device remote control.
Operators
The following operators have currently rolled out CI+ support or plan to do so:- FranceFranceThe French Republic , The French Republic , The French Republic , (commonly known as France , is a unitary semi-presidential republic in Western Europe with several overseas territories and islands located on other continents and in the Indian, Pacific, and Atlantic oceans. Metropolitan France...
- Canal+Canal+Canal+ is a French premium pay television channel launched in 1984. It is 80% owned by the Canal+ Group, which in turn is owned by Vivendi SA. The channel broadcasts several kinds of programming, mostly encrypted...
– launched the 'Canal Ready' label for devices able to receive Canal+ channel
- Canal+
- GermanyGermanyGermany , officially the Federal Republic of Germany , is a federal parliamentary republic in Europe. The country consists of 16 states while the capital and largest city is Berlin. Germany covers an area of 357,021 km2 and has a largely temperate seasonal climate...
- Kabel DeutschlandKabel Deutschland-Company:Kabel Deutschland operates in 13 of the 16 states . In 2006, of the 15.4 million households passed by their cable the company served 9.6 million, however only one third of these are direct customers of Kabel Deutschland, since especially in large apartment complexes the in-house cable...
– NDS conditional access and SMiT CAM modules will be used
- Kabel Deutschland
- NetherlandsNetherlandsThe Netherlands is a constituent country of the Kingdom of the Netherlands, located mainly in North-West Europe and with several islands in the Caribbean. Mainland Netherlands borders the North Sea to the north and west, Belgium to the south, and Germany to the east, and shares maritime borders...
- Caiway – launched CI+ in October 2009
- Delta – launched CI+ in 2010
- Kabel Noord – launched CI+ in 2010
- UPC NetherlandsUPC NetherlandsUPC Netherlands is the second largest cable operator in the Netherlands, providing cable television , broadband Internet, and telephone service to both residential and commercial customers.-History:...
– launched CI+ in 2011 - ZiggoZiggoZiggo is the largest cable operator in the Netherlands, providing cable television , broadband Internet, and telephone service to both residential and commercial customers....
– launched CI+ in September 2009, SMiT and Neotion CAM modules are used
- SwedenSwedenSweden , officially the Kingdom of Sweden , is a Nordic country on the Scandinavian Peninsula in Northern Europe. Sweden borders with Norway and Finland and is connected to Denmark by a bridge-tunnel across the Öresund....
- BoxerBoxer TV AccessBoxer TV Access is a Swedish company providing pay television channels on the digital terrestrial television network in Sweden. Modeled on the British ITV Digital, it was founded in October 1999. Some channels on the Swedish DTT are free-to-air, but most of the channels require subscription from...
- Com HemCom HemCom Hem AB of Sweden, supplies triple play services that include cable tv, digital television, broadband, telephony and HDTV.Founded in 1983 as Televerket Kabel-TV as part of the former state-owned Televerket, the company has been successively named Svenska Kabel-TV AB and Telia InfoMedia...
- Boxer
- SwitzerlandSwitzerlandSwitzerland name of one of the Swiss cantons. ; ; ; or ), in its full name the Swiss Confederation , is a federal republic consisting of 26 cantons, with Bern as the seat of the federal authorities. The country is situated in Western Europe,Or Central Europe depending on the definition....
- CablecomCablecomUPC Cablecom Holdings GmbH, trading exclusively under the brand name upc cablecom, is the largest broadband cable operator in Switzerland. Founded 1994 through multiple mergers between smaller companies, it is part of Liberty Global Europe's UPC Broadband division since the end of 2005.Cablecom...
(UPC BroadbandUPC BroadbandUPC Broadband is a Pan-European Communications company owned by Liberty Global and is active in several European countries providing bundled cable television, internet and telephone services....
) – Starting June 2010
- Cablecom
- ItalyItalyItaly , officially the Italian Republic languages]] under the European Charter for Regional or Minority Languages. In each of these, Italy's official name is as follows:;;;;;;;;), is a unitary parliamentary republic in South-Central Europe. To the north it borders France, Switzerland, Austria and...
- Mediaset PremiumMediaset PremiumMediaset Premium is an Italian digital terrestrial television service provided by Mediaset. It provides pay tv and pay-per-view services through use of a smart card.-History:...
(Digital terrestrial televisionDigital terrestrial televisionDigital terrestrial television is the technological evolution of broadcast television and advance from analog television, which broadcasts land-based signals...
) - needs CI+ slot on HD television to descramble High Definition channel Premium Calcio HD. No CI+ cams have been sold so far (the only way to receive this channel is to buy an external decoder with HDMI cable).
- Mediaset Premium
- TurkeyTurkeyTurkey , known officially as the Republic of Turkey , is a Eurasian country located in Western Asia and in East Thrace in Southeastern Europe...
- TeledünyaTeledünyaTeledünya is a Turkish digital cable TV service that was founded on November 1, 2008 by Turksat. It also provides internet by the same cable.-Channel list:...
- Teledünya
- United KingdomUnited KingdomThe 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...
- Top Up TVTop Up TVTop Up TV is a pay television service in the UK launched in March 2004, operating on the digital terrestrial platform. The aim of the service is to "Top Up" Freeview customers by providing additional channels and services....
- Top Up TV
In July 2009 the largest Cable operator in the Netherlands, Ziggo
Ziggo
Ziggo is the largest cable operator in the Netherlands, providing cable television , broadband Internet, and telephone service to both residential and commercial customers....
, announced that it will support CI+ based Integrated Digital Television
Integrated Digital Television
An Integrated Digital Television set is a television set with a built in digital tuner, be it for DVB-T, DVB-S, DVB-C, DMB-T/H, ATSC or ISDB. Most of them also allow reception of analogue signals . They do away with the need for a set top box for converting those signals for reception on a...
sets (IDTVs) actively. In September 2009 the first batch of 15,000 SMiT (Shenzhen State Micro Technology Co., Ltd.) CI+ CAMs was offered by various Dutch retailers, followed in October 2009 by the first batch of Neotion CAMs.
Other supporters include Canal+ , and conditional access companies Irdeto and Conax .
NDS announced that it will support Kabel Deutschland
Kabel Deutschland
-Company:Kabel Deutschland operates in 13 of the 16 states . In 2006, of the 15.4 million households passed by their cable the company served 9.6 million, however only one third of these are direct customers of Kabel Deutschland, since especially in large apartment complexes the in-house cable...
to deploy CI+ to its customers.
Compatible TV Sets
- LG 2010 models all LD and LE series also MFT models MXX80D.
- Many of Samsung's new LCD, LCD LED and Plasma model variants with CI+ compatible motherboards.
- Many of Sony's new models including the Bravia W5500 series.
- Philips new 5000 and 9000 series LCD TVs (required firmware pending according to Ziggo).
- Some PanasonicPanasonicPanasonic is an international brand name for Japanese electric products manufacturer Panasonic Corporation, which was formerly known as Matsushita Electric Industrial Co., Ltd...
models. It seems that even products with CI+ slots need a new firmware to be fully CI+ compatible. (Update 2010)
External links
- LinuxTV entry for common interface
- EN 50221 Specification
- ETSI TS 101 699 - DVB Extensions to the Common Interface Specification
- R206-001:1998 - Guidelines for Implementation and Use of the Common Interface for DVB Decoder Applications
- Gerard O'Driscoll, The essential Guide to Digital Set-Boxes and Interactive TV, reprinted April 2000
- Jerry whitaker, Television Receivers, 2001
- Consortium DVB
- CENELEC
- CI Plus official web site
- CI Plus Specification V1.2 (2009-04)
- Official CI Plus TrustCenter
- Official CI Plus test lab