Communication-time trade-offs in network synchronization
Proceedings of the fourth annual ACM symposium on Principles of distributed computing
Lower Bounds for Constant Depth Circuits for Prefix Problems
Proceedings of the 10th Colloquium on Automata, Languages and Programming
Property-Preserving Data Reconstruction
Algorithmica
New constructions for provably-secure time-bound hierarchical key assignment schemes
Theoretical Computer Science
Dynamic and Efficient Key Management for Access Hierarchies
ACM Transactions on Information and System Security (TISSEC)
SODA '09 Proceedings of the twentieth Annual ACM-SIAM Symposium on Discrete Algorithms
Lower bounds for local monotonicity reconstruction from transitive-closure spanners
APPROX/RANDOM'10 Proceedings of the 13th international conference on Approximation, and 14 the International conference on Randomization, and combinatorial optimization: algorithms and techniques
Local Monotonicity Reconstruction
SIAM Journal on Computing
Transitive-closure spanners: a survey
Property testing
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Given a directed graph G = (V,E) and an integer k ≥ 1, a Steiner k-transitive-closure-spanner (Steiner k-TC-spanner) of G is a directed graph H = (VH, EH) such that (1) V ⊆ VH and (2) for all vertices v, u ∈ V, the distance from v to u in H is at most k if u is reachable from v in G, and ∞ otherwise. Motivated by applications to property reconstruction and access control hierarchies, we concentrate on Steiner TC-spanners of directed acyclic graphs or, equivalently, partially ordered sets. We study the relationship between the dimension of a poset and the size, denoted Sk, of its sparsest Steiner k-TC-spanner. We present a nearly tight lower bound on S2 for d-dimensional directed hypergrids. Our bound is derived from an explicit dual solution to a linear programming relaxation of the 2-TC-spanner problem. We also give an efficient construction of Steiner 2-TC-spanners, of size matching the lower bound, for all low-dimensional posets. Finally, we present a nearly tight lower bound on Sk for d-dimensional posets.