Conditional Access Module: Encyclopedia - Conditional Access Module

Conditional Access Module

A Conditional Access Module (CAM) is an electronic device, usually incorporating a slot for a smart card, which gives a DVB television or set-top box with the appropriate hardware the facility to decrypt scrambled programmes. They are normally used with direct broadcast satellite services, although the UK digital terrestrial pay TV supplier Top Up TV also uses CAMs.

Some encryption systems for which CAMs are available are Nagravision, Viaccess, Mediaguard and Irdeto. 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 enthusiasts are multicrypt meaning each is capable of handling more than one encryption system. Matrix is more likely to be used by a novice as it can be upgraded via the PCMCIA port in a laptop personal computer whereas a Dragon cam update is done via separate programmer hardware.

The standard format for a CAM is a PCMCIA card which takes a smart card to authenticate, although CAM's with the 'smart card' burnt into memory can be found. In addition, CAM emulators exist for many systems, either providing an interface to allow the use of more than one type of card, or a card not designed for that receiver.

Adapted from the Wikipedia article "Conditional Access Module", under the G.N U Free Docmentation License. Please also see http://en.wikipedia.org/wiki