We will have two practice talks for the Crypto 2014 conference next week.

At 10:30, Tung will tell us about "Cryptography from Compression Functions: The UCE Bridge to the ROM."

At 11:00, Alex will talk about "Efficient Three-Party Computation from Cut-and-Choose"

"Cryptography from Compression Functions: The UCE Bridge to the ROM"

Abstract:
This paper suggests and explores the use of UCE security for the task of turning VIL-ROM schemes into FIL-ROM ones. The benefits we offer over indifferentiability, the current leading method for this task, are the ability to handle multi-stage games and greater efficiency. The paradigm consists of (1) Showing that a VIL UCE function can instantiate the VIL RO in the scheme, and (2) Constructing the VIL UCE function given a FIL random oracle. The main technical contributions of the paper are domain extension transforms that implement the second step. Leveraging known results for the first step we automatically obtain FIL-ROM constructions for several primitives whose security notions are underlain by multi-stage games. Our first domain extender exploits indifferentiability, showing that although the latter does not work directly for multi-stage games it can be used indirectly, through UCE, as a tool for this end. Our second domain extender targets performance. It is parallelizable and shown through implementation to provide significant performance gains over indifferentiable domain extenders.

"Efficient Three-Party Computation from Cut-and-Choose"

Abstract: With relatively few exceptions, the literature on efficient (practical) secure computation has focused on secure two-party computation (2PC). It is, in general, unclear whether the techniques used to construct practical 2PC protocols — in particular, the cut-and-choose approach — can be adapted to the multi-party setting. In this work we explore the possibility of using cut-and-choose for practical secure three-party computation. The three-party case has been studied in prior work in the semi-honest setting, and is motivated by the observation that real-world deployments of multi-party computation are likely to involve few parties. We propose a constant-round protocol for three-party computation  tolerating any number of malicious parties, whose computational cost is essentially only a small constant worse than that of state-of-the-art two-party protocols.