Card server is software which acts as a key host for card clients. Card server usually has one or more smartcard readers and ethernet interface. Card server emulates conditional access module (CAM) for accessing smartcard and offers virtual common interface to the clients.
When the user switches on an encrypted channel, the receiver uses common interface to read the decryption key from smartcard. In this case, the common interface is being emulated by client software which contacts the server requesting a valid key for the selected channel. If the card server has the ability to decode the selected channel, it responds with a valid key to client. The client then becomes able to decode encrypted video transmissions realtime with valid key acquired from the card.
A card server is often used to allow multiple cable receivers to share a single card. Some hardware based card server client modules have built-in wireless connection, which allows them to be used on receivers which lack network interface. On such devices, the client module usually connects into the CI slot.
Cable companies forbid using card servers and clients since it allows untraceable Pirate decryption. Card serving doesn't tamper with the actual card, as card cloning did. It uses the card as a normal receiver would use it to operate. Any authentication requests made against the card would validate authentic, since the emulator would pass all requests to the card in the server. This technique is often used with the help of a FTA Receiver.
- Card sharing
- Pirate decryption
- Smart card