Join us for Charles River Crypto Day on Friday, December 9 at Northeastern University.

When: Friday, December 9.

Where: 90 Snell Library, Northreastern University Campus, Boston MA 
Directions:  This link takes you to the correct building on google maps.  Also, see directions for public transportation and driving/parking. Once you enter the library go downstairs to get to room 90.

Please register (free) to attend this event by filling out this  form.
We need all attendees to register to get access to Snell library. 

Organizers: Yael Kalai, Ron Rothblum, Vinod Vaikuntanathan and Daniel Wichs.

Thanks: NSF MACS Project for their generous support.

Program:

Abstracts:

Speaker: Dana Dachman-Soled
Title: Towards Non-Black-Box Separations of Public Key Encryption and One Way Function

Abstract: Separating public key encryption from one way functions is one of the
fundamental goals of complexity-based cryptography. Beginning with the seminal
work of Impagliazzo and Rudich (STOC, 1989), a sequence of works have ruled
out certain classes of reductions from public key encryption (PKE)—or even
key agreement—to one way function. Unfortunately, known results—so called
black-box separations—do not apply to settings where the construction and/or
reduction are allowed to directly access the code, or circuit, of the one way
function. In this work, we present a meaningful, non-black-box separation
between public key encryption (PKE) and one way function.

Specifically, we introduce the notion of BBN- reductions (similar to the BBNp
reductions of Baecher et al. (ASIACRYPT, 2013)), in which the construction E
accesses the underlying primitive in a black-box way, but wherein the
universal reduction R receives the efficient code/circuit of the underlying
primitive as input and is allowed oracle access to the adversary Adv. We
additionally require that the number of oracle queries made to Adv, and the
success probability of R are independent of the run-time/circuit size of the
underlying primitive. We prove that there is no non-adaptive, BBN- reduction
from PKE to one way function, under the assumption that certain types of
strong one way functions exist. Specifically, we assume that there exists a
regular one way function f such that there is no Arthur-Merlin protocol
proving that z not in Range(f)'', where soundness holds with high
probability overno instances,” y ~ f(U_n), and Arthur may receive
polynomial-sized, non-uniform advice. This assumption is related to the
average-case analogue of the widely believed assumption coNP \not\subseteq
NP/poly.

Speaker: Leo Reyzin
Title: Scrypt is Maximally Memory-Hard

Speaker: Gillat Kol
Title: Interactive Compression for Product Distributions

Abstract: In a profoundly influential 1948 paper, Claude Shannon introduced information theory and used it to study one-way data transmission problems over different channels, both noisy and noiseless. That paper initiated the study of error correcting codes and data compression, two concepts that are especially relevant today with the rise of the internet and data-intensive applications. In the last decades, interactive communication protocols are used and studied extensively, raising the fundamental question: To what extent can Shannon’s results be generalized to the interactive setting, where parties engage in an interactive communication protocol?

In this talk we will focus on the interactive analog of data compression in an attempt to answer the above question. Specifically, we will consider the case where the parties have inputs that are independent of each other, and give a simulation protocol that communicates poly(I) bits, where I is the information cost of the original protocol. Our protocol is the first simulation protocol whose communication complexity is bounded by a polynomial in the information cost of the original protocol.

Speaker: Mike Rosulek
Title: Linicrypt: A Model for Practical Cryptography