Security of Quantum Key Recycling

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2022-9-1
Akyuz, Kaan
In cryptography, unconditional security is achieved by hiding the message under a sufficiently long one-time pad, a key that is completely unknown from outside. The one-time pad is single-use-only, because the presence of an eavesdropper is undetectable in a classical channel. In contrast, an adversary is highly detectable in a quantum channel. Quantum key recycling’s objective is to detect the adversary and re-use the one-time pad. The analysis of quantum key recycling is mainly concerned with the rate and the security of the transmission. By using a method called “smoothing”, tight bounds on these quantities can be established. Smoothing was used in a noise tolerant quantum key recycling scheme; however, only for the asymptotic case. This thesis’ primary focus is to establish more favorable bounds on the rate and security for the non-asymptotic case by using the smoothing method.

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Citation Formats
K. Akyuz, “Security of Quantum Key Recycling,” M.S. - Master of Science, Middle East Technical University, 2022.