audit trail

• decrypt on smartcard

  • can watermark each copy

• off-card solution?

  • Chameleon [Anderson]
    • long-term watermarked key block
    • watermarks secondary keys - XOR cipherstream
    • partial flaw: no protection against leaks to recent group members - MARKS [Briscoe]

• demo implementation

  • didn't include watermarking

Previous slide

Next slide

Back to first slide

View graphic version