A Brief History of Common Interface Standards
The original common interface (CI) standard for allowing access to encrypted digital TV and radio signals was published by the Digital Video Broadcasting (DVB) consortium in 1997 as DVB-CI. At the time, connecting a removable Conditional Access Module (CAM) into an external digital receiver was commonplace to decrypt subscription channels.
When High Definition (HD) broadcasts emerged in the 2000s alongside flat-screen TVs capable of decoding signals themselves, the industry shifted to an updated CI+ specification in 2008. CI+ offered higher security, better port protection, and the ability to directly insert CAMs into HDTVs with built-in tuners rather than external boxes.
Most Smart TVs today like Samsung contain CI+ slots and support both CI and CI+ CAMs. They have also implemented advanced content protection standards like HDCP 2.2 for encrypted streaming and media playback.
The Evolution of Common Interface Standards:
DVB-CI | 1997 | Original DVB standard for external receiver boxes |
CI+ or CI Plus | 2008 | Enhanced standard for HDTVs with security improvements |
CICAM | 2009 | CI+ Modules with decryption chips and firmware |
How CI+ Decryption Actually Works
The technical decryption process that CI facilitates can seem mysterious at first. Here is a step-by-step overview:
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A Smart TV tunes into a scrambled channel signal from a satellite or cable provider. This signal uses encryption algorithms to obfuscate video and audio.
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The encrypted MPEG transport stream passes into the CI+ module slotted into the TV‘s common interface. This module or CICAM contains the keys to decrypt data.
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The module uses DES, AES, or other decryption protocols to translate scrambled data so the TV can decode and display it.
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Before sending the decrypted stream back to the TV, the CI+ module re-encrypts it using a secure channel and DVB standard encryption supported by the TV.
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Built-in digital rights management prevents recording or restricts playback of re-encrypted video. HDCP 2.2 is an example protocol used.
This complex bi-directional security handshake allows providers to tightly control premium content while still utilizing CI.
The Decline of Common Interface Relevance
While most Samsung Smart TVs still support CI+ modules, statistics show their practical usage has markedly declined among consumers:
2014 | 29% of TV households | Used CI+ slot to access content |
2022 | 4% of TV households | Regularly use CI+ |
The reason comes down to shifting viewing habits and changing relationships between content providers, broadcast platforms, and television manufactures.
As on-demand streaming has displaced traditional cable and satellite, subscribers no longer need external CAMs for the latest services like Netflix or Prime Video which have their own integrated apps. Even live TV platforms like Youtube TV or Sling TV require no physical modules, despite using encryption.
Additionally, the consolidation of providers like BT Sport acquiring exclusive rights to channels once accessible via CI+ like ESPN has reduced need and availability. Other services now favor their own proprietary set-top boxes over CI, with no incentive to rely on generic TV manufacturer capabilities.
While much better connectivity and UI experiences can be achieved through native apps and OS integration, CI+ remains useful in some niche scenarios…
Where CI and CI+ Modules Are Still Relevant
Despite its decline among regular viewers, CI+ still sees viable use cases in some pockets globally:
International Satellite Providers
In Europe and Asia, standard interface CAMs remain popular ways to access regional satellite channels or ?? la carte offerings not available through local cable providers or OTT streaming:
- Canalsat in France
- Sky Deutschland in Germany
- Various channels on Astra satellites
Universities and Hotels
Large institutions like universities or hotels have existing relationships with distributors and rely on CI+ to securely provide live cable/satellite TV across campuses or rooms without needing dedicated proprietary boxes.
Obscure Niche Channels
While few in numbers, some special-interest channels focused on hobbies, sports, or languages still exclusively use CI+ encryption in various regions without a streaming presence. These keep CI relevant for their limited subscriber base.
For regular consumers though, CI and CI+ provide negligible practical benefit in 2023. Even advanced OTA encryption like Verimatrix used for antenna channels can be decoded internally by Samsung TVs today minus external CAMs.
The Future Role of Common Interface in TV Technology
Given the mature streaming landscape and push towards platform-specific applications rather than open standards, is CI destined to fade into legacy status? Or could it return with new purpose?
I predict CI will remain embedded in Smart TVs for years but in a mostly vestigial fashion for backwards compatibility. Content providers now prefer end-to-end control viarestrial apps with no incentive to rely on manufactuerer hardware. Samsung and other brands stand to gain nothing by removing CI either since costs are minimal. If CI slots disappeared, it would simply anger the few still relying on obscure channels.
In the unlikely event broadcast platforms came together again under a non-competitive banner and developed a new content protection standard, CI could theoretically see resurgence. However with the TV space rapidly innovating around concepts like modular MicroLED displays, integrated streaming, and cloud gaming, CI looks decidedly archaic. Any return would need fundamental rethinking rather than rehashing 1990s paradigms.
For the overwhelming majority reading, your Samsung Smart TV‘s built-in CI+ slot will sit unused for the lifetime of ownership. Don‘t fret about the insert labeled "Common Interface" collecting dust!