Cryptography In the Bounded QuantumStorage Model
Abstract
We initiate the study of twoparty cryptographic primitives with unconditional security, assuming that the adversary's quantum memory is of bounded size. We show that oblivious transfer and bit commitment can be implemented in this model using protocols where honest parties need no quantum memory, whereas an adversarial player needs quantum memory of size at least n/2 in order to break the protocol, where n is the number of qubits transmitted. This is in sharp contrast to the classical boundedmemory model, where we can only tolerate adversaries with memory of size quadratic in honest players' memory size. Our protocols are efficient, noninteractive and can be implemented using today's technology. On the technical side, a new entropic uncertainty relation involving minentropy is established.
 Publication:

arXiv eprints
 Pub Date:
 August 2005
 arXiv:
 arXiv:quantph/0508222
 Bibcode:
 2005quant.ph..8222D
 Keywords:

 Quantum Physics;
 Computer Science  Cryptography and Security
 EPrint:
 26 pages, full version of a paper appeared in 46th Annual IEEE Symposium on Foundations of Computer Science (FOCS), pages 449458, 2005