**Speaker: ** Periklis Papakonstantinou Tsinghua University

**Time: ** 2012-05-10 14:00-2012-05-10 15:00

**Venue: **FIT 1-222

**Abstract: **

Cryptography and its Foundations is probably the most successful area which lies in the intersection of Applications and Theory of Computing. Part of its success is due to the 1000s of constructions based on 10s of assumptions regarding cryptographic hardness. Despite this success almost every construction (but a few examples you can count on the fingers of one hand) are black-box. This means that starting from elementary primitives such as one-way functions, or trapdoor permutations one can do most of the known Private- and Public-key cryptography, where in the construction of the new primitive we do not need to care about the specific implementation (e.g. the code) of the primitive we base our construction on. To put things in context: think of the construction of a standard Private-Key Encryption constructed using e.g. a pseudo-random generator. In this construction we evaluate the generator on the given key, and the only thing we care about is that the output of the generator has the pseudo-random property.

How far can black-box techniques take us?

**Short Bio: **