The 4GB Memory Stick PRO-Duo MARK2 from Sony is a recordable media card featuring MagicGate copyright protection technology. This provides authentication and content encryption and decryption, to prevent unauthorized copying and conform to Secure Digital Music Initiative (SDMI) standards. The card is compatible with cameras and other electronic devices equipped with MS PRO-Duo slots, and can be used in MS PRO slots via the optional MSACM2 adapter.
Sony MagicGate Copyright Protection
To conform to SDMI copyright protection standards, Sony uses MagicGate technology, which provides two main functions: authentication to confirm that both Memory Stick and device using it support copyright protection, and content encryption and decryption by the device during recording or playback. If authentication is not established mutually, data exchange operations are made impossible, preventing unauthorized content copying