Browsing by Subject "Cryptography"
Now showing items 1-3 of 3
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Access control scheme for partially ordered set hierarchy with provable security
(2005)In many multi-user information systems, the users are organized as a hierarchy. Each user is a subordinate, superior and/or coordinate of some others. In such systems, a user has access to the information if and only if ... -
Indirect key derivation schemes for key management of access hierarchies
(2004)In this thesis, we study the problem of key management within an access hierarchy. Our contribution to the key management problem is an indirect key derivation approach we call the HMAC-method. It is called the HMAC-method, ... -
Visual cryptography with cheating shares
(2006)Visual cryptography is a technique that applies the human visual system to decode encrypted information, such as text, image and number, without any sophisticated devices and computing capabilities. Therefore, compared ...