49,350 research outputs found
Secret Sharing, Rank Inequalities, and Information Inequalities
Beimel and Orlov proved that all information inequalities on four or five variables, together with all information inequalities on more than five variables that are known to date, provide lower bounds on the size of the shares in secret sharing schemes that are at most linear on the number of participants. We present here another two negative results about the power of information inequalities in the search for lower bounds in secret sharing. First, we prove that all information inequalities on a bounded number of variables can only provide lower bounds that are polynomial on the number of participants. And second, we prove that the rank inequalities that are derived from the existence of two common informations can provide only lower bounds that are at most cubic in the number of participants
Secret sharing, rank inequalities, and information inequalities
© 2016 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.Beimel and Orlov proved that all information
inequalities on four or five variables, together with all information
inequalities on more than five variables that are known to date,
provide lower bounds on the size of the shares in secret sharing
schemes that are at most linear on the number of participants.
We present here another two negative results about the power of
information inequalities in the search for lower bounds in secret
sharing. First, we prove that all information inequalities on a
bounded number of variables can only provide lower bounds that
are polynomial on the number of participants. Second, we prove
that the rank inequalities that are derived from the existence of
two common informations can provide only lower bounds that
are at most cubic in the number of participants.Postprint (author's final draft
One-adhesive polymatroids
Adhesive polymatroids were defined by F. Mat\'u\v{s} motivated by entropy
functions. Two polymatroids are adhesive if they can be glued together along
their joint part in a modular way; and are one-adhesive, if one of them has a
single point outside their intersection. It is shown that two polymatroids are
one-adhesive if and only if two closely related polymatroids have any
extension. Using this result, adhesive polymatroid pairs on a five-element set
are characterized
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