20 research outputs found
A critical look at power law modelling of the Internet
This paper takes a critical look at the usefulness of power law models of the
Internet. The twin focuses of the paper are Internet traffic and topology
generation. The aim of the paper is twofold. Firstly it summarises the state of
the art in power law modelling particularly giving attention to existing open
research questions. Secondly it provides insight into the failings of such
models and where progress needs to be made for power law research to feed
through to actual improvements in network performance.Comment: To appear Computer Communication
Why the Internet Is So Small
During the last three decades the Internet has experienced fascinating evolution, both exponential growth in traffic and rapid expansion in topology. The size of the Internet becomes enormous, yet the network is very ‘small’ in the sense that it is extremely efficient to route data packets across the global Internet. This paper provides a brief review on three fundamental properties of the Internet topology at the autonomous systems (AS) level. Firstly the Internet has a power-law degree distribution, which means the majority of nodes on the Internet AS graph have small numbers of links, whereas a few nodes have very large numbers of links. Secondly the Internet exhibits a property called disassortative mixing, which means poorly-connected nodes tend to link with well-connected nodes, and vice versa. Thirdly the best-connected nodes, or the rich nodes, are tightly interconnected with each other forming a rich-club. We explain that it is these structural properties that make the global Internet so ‘small’
Network Transparency: Seeing the Neutral Network
Article published in the Northwestern Journal of Technology and Intellectual Property
Lock-Ins auf Netzeffektmärkten – Ergebnisse einer Simulationsstudie
Auf Märkten für Netzeffektgüter – wie beispielsweise Software – kommt es häufig zu so genannten Lock-Ins. Die Untersuchung von Zufallsnetzwerken sowie zwei sozialen Online-Netzwerken mithilfe eines agentenbasierten Simulationsprototypen zeigt, dass sowohl die Netzwerktopologie als auch die Netzeffektstärke einen wesentlichen Einfluss auf die Lock-In-Häufigkeit ausüben. Typischerweise steigt die Lock-In-Häufigkeit mit zunehmender Netzeffektstärke und Vermaschung der Netzwerke. In Topologien sozialer Netzwerke trifft dies jedoch nur teilweise zu
CYBER RELIABILITY OF CRITICAL PHYSICAL INFRASTRUCTURES
The paper considers the problem of constructing a full group of failure scenarios for physical infrastructures when subjected to cyber attacks (CAs). Physical infrastructures actually are systems of systems, or network of networks [1]. The main idea of the research rests on the assumption, that in order to damage any physical infrastructure by a cyber attack, it has to be able to produce a powerful enough physical impact on the most vulnerable part(s) of the infrastructure. Only civil engineering and industrial structures and installations connected to Internet and World Wide Web are considered. Hence, all infrastructures discussed below have to be elements of the Enterprise IoT or IoT, namely: electrical grids, oil, gas and product pipeline systems, water supply and disposal (waste) systems, rail networks, air traffic control and telecommunications (finance, commerce, business) networks, etc
The Dynamics of Internet Traffic: Self-Similarity, Self-Organization, and Complex Phenomena
The Internet is the most complex system ever created in human history.
Therefore, its dynamics and traffic unsurprisingly take on a rich variety of
complex dynamics, self-organization, and other phenomena that have been
researched for years. This paper is a review of the complex dynamics of
Internet traffic. Departing from normal treatises, we will take a view from
both the network engineering and physics perspectives showing the strengths and
weaknesses as well as insights of both. In addition, many less covered
phenomena such as traffic oscillations, large-scale effects of worm traffic,
and comparisons of the Internet and biological models will be covered.Comment: 63 pages, 7 figures, 7 tables, submitted to Advances in Complex
System
k-Dense communities in the Internet AS-level topology graph
In this paper we investigate the structure of the Internet by exploiting an efficient algorithm for extracting k-dense communities from the Internet AS-level topology graph. The analyses showed that the most well-connected communities consist of a small number of ASs characterized by a high level of clusterization, although they tend to direct a lot of their connections to ASs outside the community. In addition these communities are mainly composed of ASs that participate at the Internet Exchange Points (IXPs) and have a worldwide geographical scope. Regarding k-max-dense ASs we found that they play a primary role in the Internet connectivity since they are involved in a huge number of Internet connections (42% of Internet connections). We also investigated the properties of three classes of k-max-dense ASs: Content Delivery Networks, Internet Backbone Providers and Tier-1s. Specifically, we showed that CDNs and IBPs heavily exploit IXPs by participating in many of them and connecting to many IXP participant ASs. On the other hand, we found that a high percentage of connections originated by Tier-1 ASs are likely to involve national ASs which do not participate at IXPs