arXiv subjects

Jesus Gomez-Gardenes

Publications and source records attributed to Jesus Gomez-Gardenes.

24 records · Page 2Linked to original sources

arXiv2006

Immunization of Real Complex Communication Networks

Most communication networks are complex. In this paper, we address one of the fundamental problems we are facing nowadays, namely, how we can efficiently protect these networks. To this end, we study an immunization strategy and found that it works as good as targeted immunization, but using only local information about the network topology. Our findings are supported with numerical simulations of the Susceptible-Infected-Removed (SIR) model on top of real communication networks, where immune nodes are previously identified by a covering algorithm. The results provide useful hints in the way to design and deploying a digital immune system.

physics.soc-ph↗

arXiv2005

Michaelis-Menten Dynamics in Complex Heterogeneous Networks

Biological networks have been recently found to exhibit many topological properties of the so-called complex networks. It has been reported that they are, in general, both highly skewed and directed. In this paper, we report on the dynamics of a Michaelis-Menten like model when the topological features of the underlying network resemble those of real biological networks. Specifically, instead of using a random graph topology, we deal with a complex heterogeneous network characterized by a power-law degree distribution coupled to a continuous dynamics for each network's component. The dynamics of the model is very rich and stationary, periodic and chaotic states are observed upon variation of the model's parameters. We characterize these states numerically and report on several quantities such as the system's phase diagram and size distributions of clusters of stationary, periodic and chaotic nodes. The results are discussed in view of recent debate about the ubiquity of complex networks in nature and on the basis of several biological processes that can be well described by the dynamics studied.

q-bio.MN↗

arXiv2005

Distance-d covering problems in scale-free networks with degree correlations

A number of problems in communication systems demand the distributed allocation of network resources in order to provide better services, sampling and distribution methods. The solution to these issues is becoming more challenging due to the increasing size and complexity of communication networks. We report here on an heuristic method that allows to find near-optimal solutions to the covering problem in real communication networks. The results show that the optimal allocation of resources strongly depends on the topology of the underlying networks. Whether a centralized or distributed design is to be used relies upon the degree correlations between connected vertices.

cond-mat.stat-mech↗

arXiv2004

Dynamics of jamming transitions in complex networks

We numerically investigate jamming transitions in complex heterogeneous networks. Inspired by Internet routing protocols, we study a general model that incorporates local traffic information through a tunable parameter. The results show that whether the transition from a low-traffic regime to a congested phase is of first or second order type is determined by the protocol at work. The microscopic dynamics reveals that these two radically different behaviors are due to the way in which traffic jams propagate through the network. Our results are discussed in the context of Internet dynamics and other transport processes that take place on complex networks and provide insights for the design of routing policies based on traffic awareness in communication systems.

cond-mat.stat-mech↗

arXiv2004

Improved routing strategies for Internet traffic delivery

We analyze different strategies aimed at optimizing routing policies in the Internet. We first show that for a simple deterministic algorithm the local properties of the network deeply influence the time needed for packet delivery between two arbitrarily chosen nodes. We next rely on a real Internet map at the autonomous system level and introduce a score function that allows us to examine different routing protocols and their efficiency in traffic handling and packet delivery. Our results suggest that actual mechanisms are not the most efficient and that they can be integrated in a more general, though not too complex, scheme.

cond-mat.other↗

arXiv2004

Local versus Global Knowledge in the Barabasi-Albert scale-free network model

The scale-free model of Barabasi and Albert gave rise to a burst of activity in the field of complex networks. In this paper, we revisit one of the main assumptions of the model, the preferential attachment rule. We study a model in which the PA rule is applied to a neighborhood of newly created nodes and thus no global knowledge of the network is assumed. We numerically show that global properties of the BA model such as the connectivity distribution and the average shortest path length are quite robust when there is some degree of local knowledge. In contrast, other properties such as the clustering coefficient and degree-degree correlations differ and approach the values measured for real-world networks.

cond-mat.stat-mech↗