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The Common Interface is an extensible digital interconnect found in the digital TV market.
All Common Interface equipment must comply with the EN 50221-1997 standard.
The interconnect is formed between a host and a module. Examples of a host are a digital television or digital set-top box. The EN 50221 specification allows many types of module but only the Conditional Access Module (CAM) has found popularity because of the Pay TV market.
Peccavi, March 2010
