We consider the fundamental problem of authenticated group key exchange among n parties within a larger and insecure public network. A number of solutions to this problem have bee...
We revisit the definitions of zero-knowledge in the Common Reference String (CRS) model and the Random Oracle (RO) model. We argue that even though these definitions syntacticall...
We introduce captcha, an automated test that humans can pass, but current computer programs can’t pass: any program that has high success over a captcha can be used to solve an u...
Luis von Ahn, Manuel Blum, Nicholas J. Hopper, Joh...
A classical construction of stream ciphers is to combine several LFSRs and a highly non-linear Boolean function f. Their security is usually analysed in terms of correlation attack...
Cryptographic computations are often carried out on insecure devices for which the threat of key exposure represents a serious concern. Forward security allows one to mitigate the...