Protocols for Generalized Oblivious Transfer(GOT) were introduced by Ishai and Kushilevitz [10]. They built it by reducing GOT protocols to standard 1-out-of-2 oblivious transfer protocols based on private protocols. In our protocols, we provide alternative reduction by using secret sharing schemes instead of private protocols. We therefore show that there exist a natural correspondence between...

This paper uses laboratory methods to evaluate whether price-fixing conspiracies break down in the presence of opportunities to offer secret discounts. The primary treatment difference is whether or not buyer-specific discounts from the posted list price are permitted. In standard posted-offer markets, conspiring sellers are able to find and maintain near-monopoly prices. But when the possibili...

Some connections between self-dual codes, combinatorial designs and secret-sharing schemes Stefka Bouyuklieva, Zlatko Varbanov Department of Mathematics and Informatics, University of Veliko Tarnovo, Bulgaria In the present work we study a class of singly even self-dual codes with the special property that the minimum weight of their shadow is 1. Some of these codes support 1 and 2-designs. Usi...

Secret sharing schemes are one of the most important primi-tives in distributed systems. Cumulative secret sharing schemes provide a method to share a secret among a number of participants with arbitrary access structures. This paper presents two diierent methods for constructing cumulative secret sharing schemes. The rst method produces a simple and eecient cumulative scheme. The second method...

The computational soundness of formal encryption is researched extensively after the work by Abadi and Rogaway. A recent work by Abadi and Warinschi extends this work to a scenario in which secret sharing is used. A more recent work by Micciancio extends this work to deal the formal encryption in presence of key cycles by using of co-induction definition of the adversarial knowledge. In this pa...

Authoritarian elections and leadership succession, 1975-2000 Why do a substantial number of non-democratic regimes hold elections? In this paper, I exposit a model in which authoritarian rulers agree to positive levels of electoral risk primarily to reduce the threat of their violent removal from office via a coup d’etat or revolution, or to lower the cost of managing that risk through secret p...

A secret sharing scheme is a way of protecting a secret by distributing partial information to a set of participants P in such a way that only authorized subsets of P can recover the secret. The family of authorized subsets is called the access structure of the scheme. In 1979, threshold schemes were proposed to realize threshold access structures, and in 1987, multiple assignment schemes were ...

Cheater detection and identification are important issues in the process of secret reconstruction. To detect and identify cheaters most of the algorithms need the dealer to generate and distribute additional information to shareholders. Recently, algorithms have been proposed to detect and identify cheaters. If more than t (i.e. the threshold) shares, for example j (i.e. t < j) shares in the se...

The round complexity of verifiable secret sharing (VSS) schemes has been studied extensively for threshold adversaries. In particular, Fitzi et al. showed an efficient 3-round VSS for n ≥ 3t+1 [4], where an infinitely powerful adversary can corrupt t (or less) parties out of n parties. This paper shows that for non-threshold adversaries, 1. Two round VSS is possible iff the underlying adversary...

In this work we provide efficient distributed protocols for generating shares of random noise, secure against malicious participants. The purpose of the noise generation is to create a distributed implementation of the privacy-preserving statistical databases described in recent papers [14, 4, 13]. In these databases, privacy is obtained by perturbing the true answer to a database query by the ...