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arXiv · 0809.3010

Improved Upper Bounds for the Information Rates of the Secret Sharing Schemes Induced by the Vamos Matroid

Jessica Ruth Metcalf-Burton
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Abstract

An access structure specifying the qualified sets of a secret sharing scheme must have information rate less than or equal to one. The Vamos matroid induces two non-isomorphic access structures V1 and V6, which were shown by Marti-Farre and Padro to have information rates of at least 3/4. Beimel, Livne, and Padro showed that the information rates of V1 and V6 are bounded above by 10/11 and 9/10 respectively. Here we improve those upper bounds to 19/21 for V1 and 17/19 for V6.

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Jessica Ruth Metcalf-Burton. 2008-09-17. Improved Upper Bounds for the Information Rates of the Secret Sharing Schemes Induced by the Vamos Matroid. https://arxiv.org/abs/0809.3010

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