IEEE International Symposium on Information Theory (ISIT)

Classical-quantum arbitrarily varying wiretap channel: Secret message transmission under jamming attacks

Holger Boche, Minglai Cai, Christian Deppe, Janis Nötzel

Published Jun 1, 2017• 5 citations

Abstract

We analyze arbitrarily varying classical-quantum wiretap channels. These channels are subject to two attacks at the same time: one passive (eavesdropping), and one active (jamming). We progress on previous works [5] and [6] by introducing a reduced class of allowed codes that fulfills a more stringent secrecy requirement than earlier definitions. In addition, we prove that non-symmetrizability of the legal link is sufficient for equality of the deterministic and the common randomness assisted secrecy capacities. At last, we focus on analytic properties of both secrecy capacities: We completely characterize their discontinuity points, and their super-activation properties.

DOI: 10.1109/isit.2017.8006876

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Classical-quantum arbitrarily varying wiretap channel: Secret message transmission under jamming attacks

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We analyze arbitrarily varying classical-quantum wiretap channels. These channels are subject to two attacks at the same time: one passive (eavesdropping) and one active (jamming). We elaborate on our previous studies [H. Boche et al., Quantum Inf. Process. 15(11), 4853–4895 (2016) and H. Boche et al., Quantum Inf. Process. 16(1), 1–48 (2016)] by introducing a reduced class of allowable codes that fulfills a more stringent secrecy requirement than earlier definitions. In addition, we prove that non-symmetrizability of the legal link is sufficient for equality of the deterministic and the common randomness assisted secrecy capacities. Finally, we focus on analytic properties of both secrecy capacities: We completely characterize their discontinuity points and their super-activation properties.

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