Unique Information and Secret Key Decompositions

Johannes Rauh, Pradeep Kumar Banerjee, Eckehard Olbrich, and Jürgen Jost

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Submission date: 18. Dec. 2019
Pages: 9
published in: IEEE international symposium on information theory (ISIT) from July 7 to 12, 2019 ; Paris, France
Piscataway, NY : IEEE, 2019. - P. 3042 - 3046 
DOI number (of the published article): 10.1109/ISIT.2019.8849550
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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.