This article investigates complexity and approximability properties of combinatorial optimization problems yielded by the notion of Shared Risk Resource Group (SRRG).Expand

The (Gromov) hyperbolicity is a topological property of a graph, which has recently applied in several different contexts, such as the design of routing schemes, network security, computational biology, the analysis of graph algorithms, and the classification of complex networks.Expand

We consider the following Minimum Connectivity Inference problem (MCI), which arises in structural biology: given vertex sets V i ⊆ V, i ∈ I, find a graph G = (V,E) minimizing the size of the edge set E, such that the sub-graph of G induced by each V i is connected.Expand

We consider the problem of finding a lightpath assignment for a given set of communication requests on a multifiber WDM optical network with wavelength translators.Expand

We propose a concept for respecting uncertain rates of redundant traffic within the GreenRE model, closing the gap between theoretical modeling and drawn-from life data.Expand

Let G be a connected graph, and let d(a, b) denotes the shortest path distance between vertices a and b of G. The graph G is δ-hyperbolic if for any vertices a, b, c, d of G, the two largest of the… Expand

In this paper we study several graph theoretic problems for which hardness results exist such as cycle problems (triangle detection, triangle counting, girth, diameter) and maximum matchings in graphs.Expand

We show that the shortest-path metric ${\textup{d}}$ of a connected graph $G$ is ${1}/{2}$-hyperbolic if and only if it satisfies the shortest path metric of a chordless cycle of length $4$.Expand

This work has been partially funded by the European project ISTFE CRESCCO, and has been done in the context of theCRC CORSOwith France Telecom and the European action COST 293.Expand