GTACS

*** TAU, seminar room 210 Please note the unusual location. ***

In the setting of secure two-party computation, two parties wish to securely compute a
joint function of their private inputs, while revealing only the output. One of the primary

For two strings x and y, the point function P_{x,y} is defined by P_{x,y}(x') = 0 for all x' other than x'=x and P_{x,y}(x) = y. We introduce the notion of a distributed point function (DPF), which is a keyed function family Fk with the following property. Given x, y specifying a point function, one can efficiently generate a key pair (k0, k1) such that: (1) Fk0 XOR Fk1 = P_{x,y}, and (2) each of k0 and k1 hides x and y. Our main result is an efficient construction of a DPF under the (minimal) assumption that a one-way function exists.

Understanding the minimal assumptions required for carrying out cryptographic tasks is one of the fundamental goals of theoretical cryptography. A rich body of work has been dedicated to understanding the complexity of cryptographic tasks in the context of (semi-honest) secure two-party computation. Much of this work has focused on the characterization of trivial and complete functionalities (resp., functionalities that can be securely implemented unconditionally, and functionalities that can be used to securely compute all functionalities).

will describe an obfuscator for all circuits based on graded encoding schemes (a generalization of multilinear maps). This construction inspired by the previous work of Garg et al. (FOCS 13) and by our previous obfuscators for more restricted function classes. I will show that the security of this obfuscator, either as an indistinguishability obfuscator (iO) or even as a virtual black box obfuscator (VBB), can be proven in a generic model.

http://crypto.biu.ac.il/winterschool2014/

In their seminal work on non-malleability, Dolev, Dwork and Naor, showed how to construct a non-malleable commitment protocol with logarithmically-many "rounds"/"slots", the idea being that any adversary may successfully maul in some slots but would fail in at least one. Since then new ideas have been introduced, ultimately resulting in constant-round protocols based on any one-way function. Yet, in spite of this remarkable progress,
each of the known constructions leaves something to be desired.

Title: An equational approach to secure multiparty computation
Speaker: Daniele Micciancio, UCSD