Evaluation of Attacks and Countermeasures in Large Scale Networks

Computer worms represent a serious threat for modern communication infrastructures. These epidemics can cause great damage such as financial losses or interruption of critical services which support lives of citizens. These worms can spread with a speed which prevents instant human intervention. Therefore automatic detection and mitigation techniques need to be developed. However, if these techniques are not designed and intensively tested in realistic environments, they may cause even more harm as they heavily interfere with high volume communication flows. We present a simulation model which allows studies of worm spread and counter measures in large scale multi-AS topologies with millions of IP addresses.

Structure and Rheology of Cationic Molecular Hydrogels of Quinuclidine Grafted Bile Salts. Influence of the Ionic Strength and Counter-Ion type

Quinuclidine grafted cationic bile salts are forming salted hydrogels. An extensive investigation of the effect of the electrolyte and counterions on the gelation has been envisaged. The special interest of the quinuclidine grafted bile salt is due to its broader experimental range of gelation to study the effect of electrolyte. Rheological features of the hydrogels are typical of enthalpic networks exhibiting a scaling law of the elastic shear modulus with the concentration (scaling exponent 2.2) modeling cellular solids in which the bending modulus is the dominant parameter. The addition of monovalent salt (NaCl) favors the formation of gels in a first range (0.00117 g cm-3 (0.02 M) < TNaCl < 0.04675 g cm-3 (0.8 M)). At larger salt concentrations, the gels become more heterogeneous with nodal zones in the micron scale. Small-angle neutron scattering experiments have been used to characterize the rigid fibers ( ≈ 68 Å) and the nodal zones. Stress sweep and creeprecovery measurements are used to relate the lack of linear viscoelastic domain to a mechanism of disentanglement of the fibers from their associations into fagots. The electrostatic interactions can be screened by addition of salt to induce a progressive evolution toward flocculation. SEM, UV absorbance, and SAXS study of the Bragg peak at large Q-values complete the investigation.

Improving fault detection and reliability in FDDI networks

FDDI (Fibre Distributed Data Interface) is a 100 Mbit/s token ring network with two counter rotating optical rings. In this paper various possible faults (like lost token, link failures, etc.) are considered, and fault detection and the ring recovery process in case of a failure and the reliability mechanisms provided are studied. We suggest a new method to improve the fault detection and ring recovery process. The performance improvement in terms of station queue length and the average delay is compared with the performance of the existing fault detection and ring recovery process through simulation. We also suggest a modification for the physical configuration of the FDDI networks within the guidelines set by the standard to make the network more reliable. It is shown that, unlike the existing FDDI network, full connectivity is maintained among the stations even when multiple single link failures occur. A distributed algorithm is proposed for link reconfiguration of the modified FDDI network when many successive as well as simultaneous link failures occur. The performance of the modified FDDI network under link failures is studied through simulation and compared with that of the existing FDDI network.

Link failure detection for maintaining session continuity in packet data networks

A link failure in the path of a virtual circuit in a packet data network will lead to premature disconnection of the circuit by the end-points. A soft failure will result in degraded throughput over the virtual circuit. If these failures can be detected quickly and reliably, then appropriate rerouteing strategies can automatically reroute the virtual circuits that use the failed facility. In this paper, we develop a methodology for analysing and designing failure detection schemes for digital facilities. Based on errored second data, we develop a Markov model for the error and failure behaviour of a T1 trunk. The performance of a detection scheme is characterized by its false alarm probability and the detection delay. Using the Markov model, we analyse the performance of detection schemes that use physical layer or link layer information. The schemes basically rely upon detecting the occurrence of severely errored seconds (SESs). A failure is declared when a counter, that is driven by the occurrence of SESs, reaches a certain threshold.For hard failures, the design problem reduces to a proper choice;of the threshold at which failure is declared, and on the connection reattempt parameters of the virtual circuit end-point session recovery procedures. For soft failures, the performance of a detection scheme depends, in addition, on how long and how frequent the error bursts are in a given failure mode. We also propose and analyse a novel Level 2 detection scheme that relies only upon anomalies observable at Level 2, i.e. CRC failures and idle-fill flag errors. Our results suggest that Level 2 schemes that perform as well as Level 1 schemes are possible.

Influence limitation in multi-campaign social networks: A Shapley value based approach

We investigate the problem of influence limitation in the presence of competing campaigns in a social network. Given a negative campaign which starts propagating from a specified source and a positive/counter campaign that is initiated, after a certain time delay, to limit the the influence or spread of misinformation by the negative campaign, we are interested in finding the top k influential nodes at which the positive campaign may be triggered. This problem has numerous applications in situations such as limiting the propagation of rumor, arresting the spread of virus through inoculation, initiating a counter-campaign against malicious propaganda, etc. The influence function for the generic influence limitation problem is non-submodular. Restricted versions of the influence limitation problem, reported in the literature, assume submodularity of the influence function and do not capture the problem in a realistic setting. In this paper, we propose a novel computational approach for the influence limitation problem based on Shapley value, a solution concept in cooperative game theory. Our approach works equally effectively for both submodular and non-submodular influence functions. Experiments on standard real world social network datasets reveal that the proposed approach outperforms existing heuristics in the literature. As a non-trivial extension, we also address the problem of influence limitation in the presence of multiple competing campaigns.

Terrorism, Charities and Diasporas: Contrasting the fundraising practices of Hamas and al Qaeda among Muslims in Europe

Gunning, Jeroen. 'Terrorism, Charities and Diasporas: Contrasting the fundraising practices of Hamas and al Qaeda among Muslims in Europe', In: Countering the Financing of Terrorism (New York: Routledge, 2007), pp.93-125 RAE2008

The Terrorism Virus: Contemporary Traits and Mechanisms

In order to present and understand the nature of modern terrorism it is important to realize its key properties as well the mechanisms that shape terrorism. Selected properties and mechanisms shaping modern terrorism which can be exemplified by the following: evolutionary nature of terrorism, asymmetry of terrorism, interferentiality of terrorism, multitude of components of terrorism, diffusion of terrorism, duality of terrorism, positive dimension of terrorism, terrorist as the system, diversity of terrorist activity goals, changeability of terrorist threat, the broad and narrow dimension of terrorism, counter-anti-terrorism, the confrontational and cooperational character of relations, calculation and operational strategy, disintegrational nature of terrorism, multidisciplinarity of terrorism, horizontal and vertical dimension of terrorism and a the few other traits or mechanisms.

Networks, agency and (de)stabilisation: the issue of navigation on the River Wye, UK

This paper assesses the way in which an actor network presiding over the management of the River Wye has stabilized through accepting a particular view on the issue of navigation. The paper provides an account of how the network was challenged by a dissonant actor who, through reviving an old company, developed a counter network. It is argued that network stabilization is a form of consensus-building and it is contended that the way in which an issue is defined is crucial in terms of the successful enrolment of actors. The paper illustrates some of the conflicts and complexities encountered in resource planning, suggesting that research of this nature should trace actors back through time as well as through space if dynamics between actors involved in rural planning and management are to be effectively understood.

Attacking anonymous web browsing at local area networks through browsing dynamics

The majority of current anonymous systems focus on improving anonymity at the network and website level in order to defend against traffic analysis attacks. However, the vulnerability of the connections between end users and the anonymous network do not attract any attention yet. For the first time, we reveal an end user browsing dynamics based attack on anonymous browsing systems at the LAN where the victim locates. This new attack method is fundamentally different from existing attack methodologies. In general, web surfers browse the web following certain patterns, such as requesting a web page, viewing it and requesting another page. The browsing pattern of a victim can be clearly observed by a local adversary when the victim is viewing the web without protection. Unfortunately, browsing dynamics releases rich information for attacking even though the web page content is encrypted. In order to show how a local eavesdropper can decipher which pages have been viewed with the knowledge of user browsing dynamics and the public information of a given website, we established a specific hidden Markov model to represent browsing dynamics for the website. By using this model, we can then identify the optimal of the accessed pages using the Viterbi algorithm. In order to confirm the effectiveness of the revealed attack method, we have conducted extensive experiments on a real data set. The results demonstrated that the attack accuracy can be more than 80%. A few possible counter-attack strategies are discussed at the end of the paper.

Netpeace and the cosmopolitan condition : multifaith movements and the politics of understanding

The ultramodern era has been characterized paradoxically as one of great fear and great hope. Reactions to the tragic events of September 11, 2001 provide evidence of this ambivalence whereby a politics of fear and exclusion permeated Western societies, accompanied by a growing interest in collaborative cosmopolitan solutions addressing the most pressing global risks of our times. Culturally, religiously and linguistically diverse (CRALD) community experiences in the state of Victoria, Australia well illustrate this dichotomy. Drawing on this case study, I argue that the rise of multifaith and multi-actor peacebuilding networks in ultramodernity provide evidence that cosmopolitan solutions can effectively counter global risks, in this case particularly terrorism, and advance common security among diverse faith communities and across diverse sectors. In so doing I develop a new netpeace framework arguing that the politics of fear is best countered by a politics of understanding.

The multifaith movement : global risks and cosmopolitan solutions

This book documents the ultramodern rise of the multifaith movement, as mulitfaith initiatives have been increasingly deployed as cosmopolitan solutions to counter global risks such as terrorism and climate change at the turn of the 21st century. These projects aim to enhance common security, particularly in Western societies following the events of September 11, 2001 and the July 2005 London bombings, where multifaith engagement has been promoted as a strategy to counter violent extremism. The author draws on interviews with 56 leading figures in the field of multifaith relations, including Paul Knitter, Eboo Patel, Marcus Braybrooke, Katherine Marshall, John Voll and Krista Tippett.
Identifying the principle aims of the multifaith movement, the analysis explores the benefits—and challenges—of multifaith engagement, as well as the effectiveness of multifaith initiatives in countering the process of radicalization. Building on notions of cosmopolitanism, the work proposes a new theoretical framework termed ‘Netpeace’, which recognizes the interconnectedness of global problems and their solutions. In doing so, it acknowledges the capacity of multi-actor peacebuilding networks, including religious and state actors, to address the pressing dilemmas of our times. The primary intention of the book is to assist in the formation of new models of activism and governance, founded on a ‘politics of understanding’ modeled by the multifaith movement.

Are the popular users always important for information dissemination in online social networks?

This article verifies the importance of popular users in OSNs. The results are counter-intuitive. First, for dissemination speed, a large amount of users can swiftly distribute information to the masses, but they are not highly-connected users. Second, for dissemination scale, many powerful forwarders in OSNs cannot be identified by the degree measure. Furthermore, to control dissemination, popular users cannot capture most bridges of social communities.

Psychological wellbeing among same-sex attracted and heterosexual parents: Role of connectedness to family and friendship networks

© 2015 Australian Association of Family Therapy. Increasing numbers of lesbian, gay and bisexual (LGB) adults are entering into parenthood. Previous studies indicate many of these parents receive little or no support from their families of origin due to family members' negative attitudes toward homosexuality. This study looks at the extent to which LGB parents report a lower sense of connectedness to family of origin and friendship networks than heterosexual parents and whether this has an impact on psychological wellbeing in either of these groups. Data were derived from two studies of parents: Work, Love, Play, a study of Australian and New Zealand LGB parents (n=324); and the Longitudinal Study of Australian Children, a population-based study of young children and parents (n=6460). Structural equation modelling was used to explore the relationships between: parent sexuality and family/friendship connectedness, family/friendship connectedness and psychological wellbeing, parent sexuality and psychological wellbeing. LGB parents reported feeling less connected to their families of origin but more connected to their friendship groups than heterosexual parents. Counter to previous studies, we found no difference in the psychological wellbeing of LGB parents compared to heterosexual parents when examining the direct effect of sexuality on psychological wellbeing. Clinical implications for counsellors and family therapists are discussed.