In this work, we study unconditionally-secure multi-party computation (MPC) tolerating t < n/3 corruptions, where n is the total number of parties involved. In this setting, it is well known that if the underlying network is completely asynchronous, then one can achieve only statistical security; moreover it is impossible to ensure input provision and consider inputs of all the honest parties. ...

We improve certain degree bounds for Gröbner bases of polynomial ideals in generic position. We work exclusively in deterministically verifiable and achievable generic positions of a combinatorial nature, namely either strongly stable position or quasi stable position. Furthermore, we exhibit new dimension(and depth-)dependent upper bounds for the Castelnuovo-Mumford regularity and the degrees ...

The rather wide-spread belief that cosmological expansion of a flat 3D–space (with spatial curvature k = 0) cannot be observationally distinguished from a kinematics of galaxies moving in a flat and non-expanding space is erroneous. We suggest that the error may have its source in a non relativistic intuition that imagines the Universe not as a spacetime but separates space from time and pictur...

We present a new paper-based voting method with interesting security properties. The attempt here is to see if one can achieve the same security properties of recently proposed cryptographic voting protocols, but without using any cryptography, using only paper ballots. We partially succeed. (Initially, I thought the proposal accomplished this goal, but several readers discovered a vote-buying ...

Combinatorial auctions are employed into many applications such as spectrum auctions held by the Federal Communications Commission (FCC). A crucial problem in such auctions is the lack of secure and efficiency mechanism to protect the privacy of the bidding prices and to ensure data security. To solve the problem, we propose an approach to represent the price as a polynomial’s degree based on v...

We propose an efficient information theoretic secure asynchronous multiparty computation (AMPC)protocol with optimal fault tolerance; i.e., with n = 3t + 1, where n is the total number of parties andt is the number of parties that can be under the influence of a Byzantine (active) adversaryAt havingunbounded computing power. Our protocol communicates O(n5κ) bits per multiplicati...

These lecture notes introduce the notion of secure multiparty computation. We introduce some concepts necessary to define what it means for a multiparty protocol to be secure, and survey some known general results that describe when secure multiparty computation is possible. We then look at some general techniques for building secure multiparty protocols, including protocols for commitment and ...

Until now no distributed discrete-logarithm key generation (DKG) protocol is known to be universally composable. We extend Feldman’s verifiable secret sharing scheme to construct such a protocol. Our result holds for static adversaries corrupting a minority of the parties under the Decision Diffie-Hellman assumption in a weak common random string model in which the simulator does not choose the...

We argue the necessity of universally veriiable secret sharing for secrets as individual users' cryptographic keys, and propose protocols to realize such secret sharing for two most common public-key cryptosystems: discrete logarithm based and integer factorization based. The universal veriiabil-ity achieves sharing secret with multi third parties as shareholders using two-party protocols in wh...

A Key Distribution Center enables secure communications among groups of users in a network by providing common keys that can be used with a symmetric encryption algorithm to encrypt and decrypt messages the users wish to send to each other. A Distributed Key Distribution Center is a set of servers of a network that jointly realize a Key Distribution Center. In this paper we propose an unconditi...