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Copyright Protection

Ready for the Secured Digital Content

Content Protection for Recordable Media (CPRM), the content protection technology used for SD standards, is key to enabling a new distribution system for music and other commercial media. CPRM assures a high level of protection against illegal copying. The content protection technology was developed by the 4C Entity, LLC,The digital contents copyright protection technology licensing organization of IBM, Intel, Panasonic, and Toshiba.

Having a proven record in DVD, this protection is enhanced in SD standards through the use of "key revocation" technology built into each card.

The card's control circuitry allows data to be read and written (in its protection area) only when appropriate external devices are detected.

The SD memory card copyright protection function has the following features:

  • Access to an SD memory card must be enabled by authentication between devices
  • A random number is generated each time there is mutual authentication and exchange of security information