Title
Optimal Information Rate of Secret Sharing Schemes on Trees
Abstract
The information rate for an access structure is the reciprocal of the load of the optimal secret sharing scheme for this structure. We determine this value for all trees: it is $(2-1/c)^{-1}$, where $c$ is the size of the largest core of the tree. A subset of the vertices of a tree is a core if it induces a connected subgraph and for each vertex in the subset one finds a neighbor outside the subset. Our result follows from a lower and an upper bound on the information rate that applies for any graph and happen to coincide for trees because of a correspondence between the size of the largest core and a quantity related to a fractional cover of the tree with stars.
Year
DOI
Venue
2013
10.1109/TIT.2012.2236958
IEEE Transactions on Information Theory
Keywords
DocType
Volume
graph theory,information theory,security of data,access structure,core,optimal information rate,secret sharing scheme,subgraph,trees,Entropy method,fractional packing and cover,graph,information rate,secret sharing scheme
Journal
59
Issue
ISSN
Citations 
4
0018-9448
3
PageRank 
References 
Authors
0.40
2
2
Name
Order
Citations
PageRank
László Csirmaz116315.86
Gábor Tardos21261140.58