Unstructured Peer-to-Peer Botnet Simulation for Measuring Its Robustness

Malware attacks on the Internet have increasedsubstantially in recent years for which botnets are a root cause. A "botnet" is a network of compromised computers controlled by an attacker known as the "botmaster". To be able to effectively detect and defend against botnets, it is very important to have a good understanding of their construction procedure and propagation methodology. In this work, we study the construction of an unstructured peer-to-peer botnet, its propagation methodology, diurnal properties and robustness. This simulation shows that the more frequently a node updates its buddy list, the lesser is the process overhead involved

The power of indirect social ties

While direct social ties have been intensely studied in the context of computer-mediated social networks, indirect ties (e.g., friends of friends) have seen little attention. Yet in real life, we often rely on friends of our friends for recommendations (of good doctors, good schools, or good babysitters), for introduction to a new job opportunity, and for many other occasional needs. In this work we attempt to 1) quantify the strength of indirect social ties, 2) validate it, and 3) empirically demonstrate its usefulness for distributed applications on two examples. We quantify social strength of indirect ties using a(ny) measure of the strength of the direct ties that connect two people and the intuition provided by the sociology literature. We validate the proposed metric experimentally by comparing correlations with other direct social tie evaluators. We show via data-driven experiments that the proposed metric for social strength can be used successfully for social applications. Specifically, we show that it alleviates known problems in friend-to-friend storage systems by addressing two previously documented shortcomings: reduced set of storage candidates and data availability correlations. We also show that it can be used for predicting the effects of a social diffusion with an accuracy of up to 93.5%.Comment: Technical Repor

Territoriality in diurnal raptors: relative roles of recent evolution, diet and nest site

Animal territoriality, defined here as defence of well-delimited breeding areas to exclude competitors, has beenwidely studied. However, the phylogenetic and ecological characteristics influencing the variation in the expressionof this behaviour are poorly understood. We evaluated the effect of phylogeny and key ecological factors on territorialbehaviour and territory size in diurnal raptors from the western Palearctic and New World. To our knowledge, ourwork is the first comparative analysis of raptor territorial behaviour and territory size that accounts for phylogeneticrelationships. One important finding is that territorial behaviour has not been strongly conserved across evolutionarytime, but differences in territoriality of diurnal raptors have been influenced by recent evolution, which has ledto variations of this behaviour in response to changes in climate and habitat. Raptor current ecology is also associatedwith the expression of these traits. Species that capture more agile prey and nest in more protected sites weremost likely to be territorial. Additionally, territorial species that are bigger and capture more agile and bigger preydefended larger territories than species feeding on more vulnerable and smaller prey. We discuss potential mechanismsfor these patterns and the implications of our findings for future research on avian territoriality.Comisión Interministerial de Ciencia y Tecnología-CICYTREMEDINALMinisterio de Educación y Cienci