Sciweavers

Share
SCN
2010
Springer

How to Pair with a Human

8 years 6 months ago
How to Pair with a Human
We introduce a protocol, that we call Human Key Agreement, that allows pairs of humans to establish a key in a (seemingly hopeless) case where no public-key infrastructure is available, the users do not share any common secret, and have never been connected by any physically-secure channel. Our key agreement scheme, while vulnerable to the human-in-themiddle attacks, is secure against any malicious machine-in-the middle. The only assumption that we make is that the attacker is a machine that is not able to break the Captcha puzzles (introduced by von Ahn et al., EUROCRYPT 2003). Our main tool is a primitive that we call a Simultaneous Turing Test, which is a protocol that allows two users to verify if they are both human, in such a way that if one of them is not a human, then he does not learn whether the other one is human, or not. To construct this tool we use a Universally-Composable Password Authenticated Key Agreement of Canetti et al. (EUROCRYPT 2005).
Stefan Dziembowski
Added 30 Jan 2011
Updated 30 Jan 2011
Type Journal
Year 2010
Where SCN
Authors Stefan Dziembowski
Comments (0)
books