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REPORTS > KEYWORD > SECRET SHARING:
Reports tagged with secret sharing:
TR15-182 | 13th November 2015
Andrej Bogdanov, Yuval Ishai, Emanuele Viola, Christopher Williamson

#### Bounded Indistinguishability and the Complexity of Recovering Secrets

Revisions: 1

We say that a function $f\colon \Sigma^n \to \{0, 1\}$ is $\epsilon$-fooled by $k$-wise indistinguishability if $f$ cannot distinguish with advantage $\epsilon$ between any two distributions $\mu$ and $\nu$ over $\Sigma^n$ whose projections to any $k$ symbols are identical. We study the class of functions $f$ that are fooled by ... more >>>

TR16-023 | 23rd February 2016
Ilan Komargodski, Moni Naor, Eylon Yogev

#### How to Share a Secret, Infinitely

Revisions: 4

Secret sharing schemes allow a dealer to distribute a secret piece of information among several parties so that any qualified subset of parties can reconstruct the secret, while every unqualified subset of parties learns nothing about the secret. The collection of qualified subsets is called an access structure. The best ... more >>>

TR16-064 | 19th April 2016
Stephen A. Cook, Toniann Pitassi, Robert Robere, Benjamin Rossman

#### Exponential Lower Bounds for Monotone Span Programs

Monotone span programs are a linear-algebraic model of computation which were introduced by Karchmer and Wigderson in 1993. They are known to be equivalent to linear secret sharing schemes, and have various applications in complexity theory and cryptography. Lower bounds for monotone span programs have been difficult to obtain because ... more >>>

TR16-131 | 21st August 2016
Andrej Bogdanov, Siyao Guo, Ilan Komargodski

#### Threshold Secret Sharing Requires a Linear Size Alphabet

We prove that for every $n$ and $1 < t < n$ any $t$-out-of-$n$ threshold secret sharing scheme for one-bit secrets requires share size $\log(t + 1)$. Our bound is tight when $t = n - 1$ and $n$ is a prime power. In 1990 Kilian and Nisan proved ... more >>>

TR17-038 | 23rd February 2017
Benny Applebaum, Barak Arkis, Pavel Raykov, Prashant Nalini Vasudevan

#### Conditional Disclosure of Secrets: Amplification, Closure, Amortization, Lower-bounds, and Separations

Revisions: 1

In the \emph{conditional disclosure of secrets} problem (Gertner et al., J. Comput. Syst. Sci., 2000) Alice and Bob, who hold inputs $x$ and $y$ respectively, wish to release a common secret $s$ to Carol (who knows both $x$ and $y$) if only if the input $(x,y)$ satisfies some predefined predicate ... more >>>

TR17-051 | 16th March 2017
Mark Bun, Justin Thaler

#### A Nearly Optimal Lower Bound on the Approximate Degree of AC$^0$

The approximate degree of a Boolean function $f \colon \{-1, 1\}^n \rightarrow \{-1, 1\}$ is the least degree of a real polynomial that approximates $f$ pointwise to error at most $1/3$. We introduce a generic method for increasing the approximate degree of a given function, while preserving its computability by ... more >>>

TR17-076 | 21st April 2017
Tianren Liu, Vinod Vaikuntanathan, Hoeteck Wee

#### New Protocols for Conditional Disclosure of Secrets (and More)

Revisions: 2

We present new protocols for conditional disclosure of secrets (CDS),
where two parties want to disclose a secret to a third party if and
only if their respective inputs satisfy some predicate.

- For general predicates $\text{pred} : [N] \times [N] \rightarrow \{0,1\}$,
we present two protocols that achieve ... more >>>

TR17-165 | 3rd November 2017
Toniann Pitassi, Robert Robere

#### Lifting Nullstellensatz to Monotone Span Programs over Any Field

We characterize the size of monotone span programs computing certain "structured" boolean functions by the Nullstellensatz degree of a related unsatisfiable Boolean formula.

This yields the first exponential lower bounds for monotone span programs over arbitrary fields, the first exponential separations between monotone span programs over fields of different ... more >>>

TR17-189 | 25th December 2017
Benny Applebaum, Barak Arkis

#### Conditional Disclosure of Secrets and $d$-Uniform Secret Sharing with Constant Information Rate

Revisions: 1

Consider the following secret-sharing problem. Your goal is to distribute a long file $s$ between $n$ servers such that $(d-1)$-subsets cannot recover the file, $(d+1)$-subsets can recover the file, and $d$-subsets should be able to recover $s$ if and only if they appear in some predefined list $L$. How small ... more >>>

TR18-143 | 16th August 2018
Mark Bun, Justin Thaler

#### The Large-Error Approximate Degree of AC$^0$

We prove two new results about the inability of low-degree polynomials to uniformly approximate constant-depth circuits, even to slightly-better-than-trivial error. First, we prove a tight $\tilde{\Omega}(n^{1/2})$ lower bound on the threshold degree of the Surjectivity function on $n$ variables. This matches the best known threshold degree bound for any AC$^0$ ... more >>>

TR18-200 | 29th November 2018
Ashutosh Kumar, Raghu Meka, Amit Sahai

#### Leakage-Resilient Secret Sharing

In this work, we consider the natural goal of designing secret sharing schemes that ensure security against a powerful adaptive adversary who may learn some leaked'' information about all the shares. We say that a secret sharing scheme is $p$-party leakage-resilient, if the secret remains statistically hidden even after an ... more >>>

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