Simulating independence: new constructions of condensers, ramsey graphs, dispersers, and extractors
Proceedings of the thirty-seventh annual ACM symposium on Theory of computing
How to Encrypt with a Malicious Random Number Generator
Fast Software Encryption
An Improved Robust Fuzzy Extractor
SCN '08 Proceedings of the 6th international conference on Security and Cryptography for Networks
Non-malleable extractors and symmetric key cryptography from weak secrets
Proceedings of the forty-first annual ACM symposium on Theory of computing
A new algorithm for encryption/decryption for field applications
Computer Standards & Interfaces
Simulating independence: New constructions of condensers, ramsey graphs, dispersers, and extractors
Journal of the ACM (JACM)
Does privacy require true randomness?
TCC'07 Proceedings of the 4th conference on Theory of cryptography
Detection of algebraic manipulation with applications to robust secret sharing and fuzzy extractors
EUROCRYPT'08 Proceedings of the theory and applications of cryptographic techniques 27th annual international conference on Advances in cryptology
Obfuscating point functions with multibit output
EUROCRYPT'08 Proceedings of the theory and applications of cryptographic techniques 27th annual international conference on Advances in cryptology
Secret keys from channel noise
EUROCRYPT'11 Proceedings of the 30th Annual international conference on Theory and applications of cryptographic techniques: advances in cryptology
On the impossibility of extracting classical randomness using a quantum computer
ICALP'06 Proceedings of the 33rd international conference on Automata, Languages and Programming - Volume Part II
Key generation based on elliptic curve over finite prime field
International Journal of Electronic Security and Digital Forensics
Distributed computing with imperfect randomness
DISC'05 Proceedings of the 19th international conference on Distributed Computing
Robust fuzzy extractors and authenticated key agreement from close secrets
CRYPTO'06 Proceedings of the 26th annual international conference on Advances in Cryptology
Separating sources for encryption and secret sharing
TCC'06 Proceedings of the Third conference on Theory of Cryptography
Encryption with weakly random keys using a quantum ciphertext
Quantum Information & Computation
ICITS'12 Proceedings of the 6th international conference on Information Theoretic Security
| Hi-index | 0.00 |
Randomization is vital in cryptography: secret keys should be randomly generated and most cryptographic primitives (e.g., encryption) must be probabilistic. As a common abstraction, it is assumed that there is a source of truly random bits available to all the participants of the system. While convenient, this assumption is often highly unrealistic, and cryptographic systems have to be built based on imperfect sources of randomness. Remarkably, this fundamental problem has received little or no attention so far, despite the fact that a related question of simulating probabilistic (BPP) algorithms with imperfect random sources has a long and rich history.In this work we initiate the quantitative study concerning feasibility of building secure cryptographic primitives using imperfect random sources. Specifically, we concentrate on symmetric-key encryption and message authentication, where the shared secret key comes from an imperfect random source instead of being assumed truly random. In each case, we compare the class of "cryptographic" sources for the task at hand with the classes of "extractable" and "simulatable" sources, where: (1) "cryptographic" refers to sources for which the corresponding symmetric-key primitive can be build; (2) "extractable" refers to a very narrow class of sources from which one can extract nearly perfect randomness; and (3) "simulatable" refers to a very general class of weak random sources which are known to suffice for BPP simulation. For both encryption and authentication, we show that the corresponding cryptographic sources lie strictly in between extractable and simulatable sources, which implies that "cryptographic usage" of randomness is more demanding than the corresponding "algorithmic usage", but still does not require perfect randomness. Interestingly,cryptographic sources for encryption and authentication are also quite different from each other, which suggests that there might not be an elegant way to describe imperfect sources sufficient for "general cryptographic use". We believe that our initial investigation in this new area will inspire a lot of further research.