26 research outputs found
Optimization in Networks
The recent surge in the network modeling of complex systems has set the stage
for a new era in the study of fundamental and applied aspects of optimization
in collective behavior. This Focus Issue presents an extended view of the state
of the art in this field and includes articles from a large variety of domains
where optimization manifests itself, including physical, biological, social,
and technological networked systems.Comment: Opening article of the CHAOS Focus Issue "Optimization in Networks",
available at http://link.aip.org/link/?CHA/17/2/htmlto
Congestion-gradient driven transport on complex networks
We present a study of transport on complex networks with routing based on
local information. Particles hop from one node of the network to another
according to a set of routing rules with different degrees of congestion
awareness, ranging from random diffusion to rigid congestion-gradient driven
flow. Each node can be either source or destination for particles and all nodes
have the same routing capacity, which are features of ad-hoc wireless networks.
It is shown that the transport capacity increases when a small amount of
congestion awareness is present in the routing rules, and that it then
decreases as the routing rules become too rigid when the flow becomes strictly
congestion-gradient driven. Therefore, an optimum value of the congestion
awareness exists in the routing rules. It is also shown that, in the limit of a
large number of nodes, networks using routing based on local information jam at
any nonzero load. Finally, we study the correlation between congestion at node
level and a betweenness centrality measure.Comment: 11 pages, 8 figure