Paper 2017/331
Optimal attacks on qubit-based Quantum Key Recycling
Daan Leermakers and Boris Skoric
Abstract
Quantum Key Recycling (QKR) is a quantum-cryptographic primitive that allows one to re-use keys in an unconditionally secure way. By removing the need to repeatedly generate new keys it improves communication efficiency. Škorić and de Vries recently proposed a QKR scheme based on 8-state encoding (four bases). It does not require quantum computers for encryption/decryption but only single-qubit operations. We provide a missing ingredient in the security analysis of this scheme in the case of noisy channels: accurate bounds on the privacy amplification. We determine optimal attacks against the message and against the key, for 8-state encoding as well as 4-state and 6-state conjugate coding. We show that the Shannon entropy analysis for 8-state encoding reduces to the analysis of Quantum Key Distribution, whereas 4-state and 6-state suffer from additional leaks that make them less effective. We also provide results in terms of the min-entropy. Overall, 8-state encoding yields the highest capacity.
Metadata
- Available format(s)
-
PDF
- Publication info
- Preprint. MINOR revision.
- Keywords
- quantum cryptographyquantum key recycling
- Contact author(s)
- b skoric @ tue nl
- History
- 2017-04-17: received
- Short URL
- https://ia.cr/2017/331
- License
-
CC BY
BibTeX
@misc{cryptoeprint:2017/331,
author = {Daan Leermakers and Boris Skoric},
title = {Optimal attacks on qubit-based Quantum Key Recycling},
howpublished = {Cryptology {ePrint} Archive, Paper 2017/331},
year = {2017},
url = {https://eprint.iacr.org/2017/331}
}
