In a limited-copy protection scheme, a check-out/check-in system is configured to a) verify that the receiving device is a certified conforming device, and b) verify that the device that checks-in content material is the same device that checked-out the content material. The verification of the receiving device is effected via a conventional certification process. The verification that the same device is used for check-in and check-out is effected via a secure challenge-response protocol. As contrast to a conventional contemporaneous challenge-response protocol, the system provides a challenge that is specific to the receiving device when the content material is checked-out, and verifies the appropriate response when the content material is checked-in. Because the challenge-response is specific to the receiving device, only the device that receives the challenge when the content material is checked-out can provide the appropriate response when the content material is checked-in.

 
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> Deterring unauthorized use of electronic devices

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