The Computer Science Colloquium
Thursday, April 15, 4:15pm, room 9204/05
Nelly Fazio
"Group-Theoretic Cryptography: Respice, Adspice, Prospice"
This talk outlines an ongoing research effort towards a probabilistic
framework for the application of infinite groups to cryptography.
We start by analyzing a classical group-theoretic construction for
public-key cryptosystems from a complexity-theoretic perspective. We
then suggest a way of casting some of the standard computational
problems from group theory in terms of probabilistic cryptographic
assumptions---an essential ingredient for a formal security analysis.
Next, we outline a new approach for finding cryptographically-suitable
group-theoretic assumptions, inspired by recent advances in
lattice-based cryptography. The framework relies on a new problem
that we term ``Learning Homomorphisms from Images with Errors''
(LHIE), which can be viewed as a generalization of the ``Learning With
Errors'' (LWE) problem from the setting of vector spaces and linear
transformations to the setting of groups and homomorphisms. We
conclude by discussing how this assumption yields group-theoretic
public-key cryptosystems, and describe some of the remaining
challenges in this effort.
The Colloquium is supported by generous contributions from
the Bloomberg, Information Builders, Inc., and Netlogic,
Inc.
365 Fifth Ave, New York City 10016 | Room 4319 | Phone: 212.817.8190 | Fax: 212.817.1510 | compsci@gc.cuny.edu


