— Integrity of digital documents is a very important issue if they are to be legally binding. Common solutions, like digital signatures or message authentication codes, are based...
The ElGamal encryption scheme has been proposed several years ago and is one of the few probabilistic encryption schemes. However, its security has never been concretely proven bas...
We deal with computational assumptions needed in order to design secure cryptographic schemes. We suggest a classi£cation of such assumptions based on the complexity of falsifying...
The recent attack on Apple iTunes Digital Rights Management [17] has brought to light the usefulness of proxy re-encryption schemes for Digital Rights Management. It is known that...
Customers are usually passive in an electronic commerce transaction. Based on a new two times concurrent signature, this article presents a fair electronic payment (E-payment) pro...