Conditional-access module

A conditional access module (CAM) 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. They are normally used with direct-broadcast satellite (DBS) services, although digital terrestrial pay TV suppliers also use CAMs. PC Card form factor is used as the Common Interface form of Conditional Access Modules for DVB broadcasts.

Some encryption systems for which CAMs are available are Logiways, Nagravision, Viaccess, Mediaguard, Irdeto, KeyFly, Verimatrix, Cryptoworks, Mascom, Safeview, Diablo CAM and Conax. NDS VideoGuard encryption, the preferred choice of Sky Digital can only be externally emulated by a Dragon brand cam. The NDS CAM which the Sky viewing card ordinarily uses is built into the Sky Digibox thus not visible. Dragon and Matrix, two popular cams with satellite television enthusiasts are multicrypt meaning each is capable of handling more than one encryption system. Matrix CAMs can be upgraded via the PC Card port in a laptop personal computer whereas a Dragon cam update is done via separate programmer hardware.

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