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arXiv · 1901.08007

Unique Information and Secret Key Decompositions

Johannes Rauh·Pradeep Kr. Banerjee·Eckehard Olbrich·Jürgen Jost
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Abstract

The unique information ($UI$) is an information measure that quantifies a deviation from the Blackwell order. We have recently shown that this quantity is an upper bound on the one-way secret key rate. In this paper, we prove a triangle inequality for the $UI$, which implies that the $UI$ is never greater than one of the best known upper bounds on the two-way secret key rate. We conjecture that the $UI$ lower bounds the two-way rate and discuss implications of the conjecture.

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Johannes Rauh, Pradeep Kr. Banerjee, Eckehard Olbrich, Jürgen Jost. 2019-01-23. Unique Information and Secret Key Decompositions. https://doi.org/10.1109/isit.2019.8849550

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