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STOC '86 Proceedings of the eighteenth annual ACM symposium on Theory of computing
STOC '87 Proceedings of the nineteenth annual ACM symposium on Theory of computing
Completeness theorems for non-cryptographic fault-tolerant distributed computation
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Multiparty unconditionally secure protocols
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On the existence of pseudorandom generators
SIAM Journal on Computing
Random oracles are practical: a paradigm for designing efficient protocols
CCS '93 Proceedings of the 1st ACM conference on Computer and communications security
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SIAM Journal on Computing
Adaptively secure multi-party computation
STOC '96 Proceedings of the twenty-eighth annual ACM symposium on Theory of computing
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ICALP '00 Proceedings of the 27th International Colloquium on Automata, Languages and Programming
CRYPTO '00 Proceedings of the 20th Annual International Cryptology Conference on Advances in Cryptology
Pricing via Processing or Combatting Junk Mail
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Time-lock Puzzles and Timed-release Crypto
Time-lock Puzzles and Timed-release Crypto
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FOCS '06 Proceedings of the 47th Annual IEEE Symposium on Foundations of Computer Science
Zero-knowledge proofs of knowledge without interaction
SFCS '92 Proceedings of the 33rd Annual Symposium on Foundations of Computer Science
The exact security of digital signatures-how to sign with RSA and Rabin
EUROCRYPT'96 Proceedings of the 15th annual international conference on Theory and application of cryptographic techniques
Lower bounds for discrete logarithms and related problems
EUROCRYPT'97 Proceedings of the 16th annual international conference on Theory and application of cryptographic techniques
Uniform Direct Product Theorems: Simplified, Optimized, and Derandomized
SIAM Journal on Computing
Efficient pseudorandom generators from exponentially hard one-way functions
ICALP'06 Proceedings of the 33rd international conference on Automata, Languages and Programming - Volume Part II
Resource Fairness and Composability of Cryptographic Protocols
Journal of Cryptology
Perfectly secure multiparty computation and the computational overhead of cryptography
EUROCRYPT'10 Proceedings of the 29th Annual international conference on Theory and Applications of Cryptographic Techniques
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In the setting of cryptographic protocols, the corruption of a party has traditionally been viewed as a simple, uniform and atomic operation, where the adversary decides to get control over a party and this party immediately gets corrupted. In this paper, motivated by the fact that different players may require different resources to get corrupted, we put forth the notion of resource-based corruptions, where the adversary must invest some resources in order to corrupt a player. If the adversary has full information about the system configuration then resource-based corruptions would provide no fundamental difference from the standard corruption model. However, in a resource "anonymous" setting, in the sense that such configuration is hidden from the adversary, much is to be gained in terms of efficiency and security. We showcase the power of such hidden diversity in the context of secure multiparty computation (MPC) with resource-based corruptions and prove that anonymity it can effectively be used to circumvent known impossibility results. Specifically, if OPT is the corruption budget that violates the completeness of MPC (the case when half or more of the players are corrupted), we show that if hidden diversity is available, the completeness of MPC can be made to hold against an adversary with as much as a B ⋅ OPT budget, for any constant B1. This result requires a suitable choice of parameters (in terms of number of players and their hardness to corrupt), which we provide and further prove other tight variants of the result when the said choice is not available. Regarding efficiency gains, we show that hidden diversity can be used to force the corruption threshold to drop from 1/2 to 1/3, in turn allowing the use of much more efficient (information-theoretic) MPC protocols. We achieve the above through a series of technical contributions: The modeling of the corruption process in the setting of cryptographic protocols through corruption oracles as well as the introduction of a notion of reduction to relate such oracles; the abstraction of the corruption game as a combinatorial problem and its analysis; and, importantly, the formulation of the notion of inversion effort preserving (IEP) functions which is a type of direct-sum property, and the property of hardness indistinguishability. While hardness indistinguishability enables the dissociation of parties' identities and the resources needed to corrupt them, IEP enables the discretization of adversarial work into corruption tokens, all of which may be of independent interest.