title: Evolution of robust network topologies: emergence of central backbones.
abstract: We model the robustness against random failure or an intentional attack of networks with an arbitrary large-scale structure. We construct a block-based model which incorporates--in a general fashion--both connectivity and interdependence links, as well as arbitrary degree distributions and block correlations. By optimizing the percolation properties of this general class of networks, we identify a simple core-periphery structure as the topology most robust against random failure. In such networks, a distinct and small "core" of nodes with higher degree is responsible for most of the connectivity, functioning as a central "backbone" of the system. This centralized topology remains the optimal structure when other constraints are imposed, such as a given fraction of interdependence links and fixed degree distributions. This distinguishes simple centralized topologies as the most likely to emerge, when robustness against failure is the dominant evolutionary force.
authors.affiliation: Institut für Theoretische Physik, Universität Bremen, Hochschulring 18, D-28359 Bremen, Germany. tiago@itp.uni-bremen.de
authors.forename: Tiago P
authors.initials: TP
authors.lastname: Peixoto
authors.forename: Stefan
authors.initials: S
authors.lastname: Bornholdt