dorsal/arxiv
View SchemaThe Universal Composable Security of Quantum Key Distribution
| Authors | M. Ben-Or, Michal Horodecki, D. W. Leung, D. Mayers, J. Oppenheim |
|---|---|
| Categories | |
| ArXiv ID | quant-ph/0409078 |
| URL | https://arxiv.org/abs/quant-ph/0409078 |
| Journal | Theory of Cryptography: Second Theory of Cryptography Conference, TCC 2005, J.Kilian (ed.) Springer Verlag 2005, vol. 3378 of Lecture Notes in Computer Science, pp. 386-406 |
Abstract
The existing unconditional security definitions of quantum key distribution (QKD) do not apply to joint attacks over QKD and the subsequent use of the resulting key. In this paper, we close this potential security gap by using a universal composability theorem for the quantum setting. We first derive a composable security definition for QKD. We then prove that the usual security definition of QKD still implies the composable security definition. Thus, a key produced in any QKD protocol that is unconditionally secure in the usual definition can indeed be safely used, a property of QKD that is hitherto unproven. We propose two other useful sufficient conditions for composability. As a simple application of our result, we show that keys generated by repeated runs of QKD degrade slowly.
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"abstract": "The existing unconditional security definitions of quantum key distribution\n(QKD) do not apply to joint attacks over QKD and the subsequent use of the\nresulting key. In this paper, we close this potential security gap by using a\nuniversal composability theorem for the quantum setting. We first derive a\ncomposable security definition for QKD. We then prove that the usual security\ndefinition of QKD still implies the composable security definition. Thus, a key\nproduced in any QKD protocol that is unconditionally secure in the usual\ndefinition can indeed be safely used, a property of QKD that is hitherto\nunproven. We propose two other useful sufficient conditions for composability.\nAs a simple application of our result, we show that keys generated by repeated\nruns of QKD degrade slowly.",
"arxiv_id": "quant-ph/0409078",
"authors": [
"M. Ben-Or",
"Michal Horodecki",
"D. W. Leung",
"D. Mayers",
"J. Oppenheim"
],
"categories": [
"quant-ph"
],
"journal_ref": "Theory of Cryptography: Second Theory of Cryptography Conference,\n TCC 2005, J.Kilian (ed.) Springer Verlag 2005, vol. 3378 of Lecture Notes in\n Computer Science, pp. 386-406",
"title": "The Universal Composable Security of Quantum Key Distribution",
"url": "https://arxiv.org/abs/quant-ph/0409078"
},
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