530 research outputs found
A new design principle of robust onion-like networks self-organized in growth
Today's economy, production activity, and our life are sustained by social
and technological network infrastructures, while new threats of network attacks
by destructing loops have been found recently in network science. We inversely
take into account the weakness, and propose a new design principle for
incrementally growing robust networks. The networks are self-organized by
enhancing interwoven long loops. In particular, we consider the range-limited
approximation of linking by intermediations in a few hops, and show the strong
robustness in the growth without degrading efficiency of paths. Moreover, we
demonstrate that the tolerance of connectivity is reformable even from
extremely vulnerable real networks according to our proposed growing process
with some investment. These results may indicate a prospective direction to the
future growth of our network infrastructures.Comment: 21 pages, 10 figures, 1 tabl
An approximative calculation of the fractal structure in self-similar tilings
Fractal structures emerge from statistical and hierarchical processes in
urban development or network evolution. In a class of efficient and robust
geographical networks, we derive the size distribution of layered areas, and
estimate the fractal dimension by using the distribution without huge
computations. This method can be applied to self-similar tilings based on a
stochastic process.Comment: 5 pages, 6 figure
Simple Derivation of the Lifetime and the Distribution of Faces for a Binary Subdivision Model
The iterative random subdivision of rectangles is used as a generation model
of networks in physics, computer science, and urban planning. However, these
researches were independent. We consider some relations in them, and derive
fundamental properties for the average lifetime depending on birth-time and the
balanced distribution of rectangle faces.Comment: 2 figure
Recoverable DTN Routing based on a Relay of Cyclic Message-Ferries on a MSQ Network
An interrelation between a topological design of network and efficient
algorithm on it is important for its applications to communication or
transportation systems. In this paper, we propose a design principle for a
reliable routing in a store-carry-forward manner based on autonomously moving
message-ferries on a special structure of fractal-like network, which consists
of a self-similar tiling of equilateral triangles. As a collective adaptive
mechanism, the routing is realized by a relay of cyclic message-ferries
corresponded to a concatenation of the triangle cycles and using some good
properties of the network structure. It is recoverable for local accidents in
the hierarchical network structure. Moreover, the design principle is
theoretically supported with a calculation method for the optimal service rates
of message-ferries derived from a tandem queue model for stochastic processes
on a chain of edges in the network. These results obtained from a combination
of complex network science and computer science will be useful for developing a
resilient network system.Comment: 6 pages, 12 figures, The 3rd Workshop on the FoCAS(Fundamentals of
Collective Adaptive Systems) at The 9th IEEE International Conference on
SASO(Self-Adaptive and Self-Organizing systems), Boston, USA, Sept.21, 201
Spatially self-organized resilient networks by a distributed cooperative mechanism
The robustness of connectivity and the efficiency of paths are incompatible
in many real networks. We propose a self-organization mechanism for
incrementally generating onion-like networks with positive degree-degree
correlations whose robustness is nearly optimal. As a spatial extension of the
generation model based on cooperative copying and adding shortcut, we show that
the growing networks become more robust and efficient through enhancing the
onion-like topological structure on a space. The reasonable constraint for
locating nodes on the perimeter in typical surface growth as a self-propagation
does not affect these properties of the tolerance and the path length.
Moreover, the robustness can be recovered in the random growth damaged by
insistent sequential attacks even without any remedial measures.Comment: 34 pages, 12 figures, 2 table
Asymptotic behavior of the node degrees in the ensemble average of adjacency matrix
Various important and useful quantities or measures that characterize the
topological network structure are usually investigated for a network, then they
are averaged over the samples. In this paper, we propose an explicit
representation by the beforehand averaged adjacency matrix over samples of
growing networks as a new general framework for investigating the
characteristic quantities. It is applied to some network models, and shows a
good approximation of degree distribution asymptotically. In particular, our
approach will be applicable through the numerical calculations instead of
intractable theoretical analysises, when the time-course of degree is a
monotone increasing function like power-law or logarithm.Comment: 13 paghes, 7 figure
- …