Fully Simulatable Quantum-Secure Coin-Flipping and Applications

We propose a coin-flip protocol which yields a string of strong, random coins and is fully simulatable against poly-sized quantum adversaries on both sides. It can be implemented with quantum-computational security without any set-up assumptions, since our construction only assumes mixed commitment schemes which we show how to construct in the given setting. We then show that the interactive generation of random coins at the beginning or during outer protocols allows for quantum-secure realizations of classical schemes, again without any set-up assumptions. As example applications we discuss quantum zero-knowledge proofs of knowledge and quantum-secure two-party function evaluation. Both applications assume only fully simulatable coin-flipping and mixed commitment schemes. Since our framework allows to construct fully simulatable coin-flipping from mixed commitment schemes, this in particular shows that mixed commitment schemes are complete for quantum-secure two-party function eval...

• Type: Journal
• Year: 2011
• Where: CORR
• Authors: Carolin Lunemann, Jesper Buus Nielsen
• Keywords: Commitment Schemes, CORR 2011, Education, Mixed Commitment Schemes, Two-party Function Evaluation