Improved upper bounds for the information rates of the secret sharing schemes induced by the Vámos matroid
نویسنده
چکیده
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 Mart́ı-Farré and Padró to have information rates of at least 3/4. Beimel, Livne, and Padró 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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عنوان ژورنال:
- Discrete Mathematics
دوره 311 شماره
صفحات -
تاریخ انتشار 2011