209 resultados para DDoS attacks


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Plasmodiophora brassicae is a protistan pathogen that attacks roots of brassicaceous plant species causing devastating disease. Resistance is characterised by restriction of the pathogen and susceptibility by the development of severely malformed roots (‘clubroots’) and stunting of the plant that is associated with alterations in the synthesis of cytokinin and auxin hormones. We are examining the susceptible response in Arabidopsis and whether suppression of key resistance factors by the pathogen contributes to susceptibility. The interaction is being studied using a number of approaches including microscopy of the infection process and development of the pathogen within roots and host gene expression analysis. Quantitative PCR was used to confirm the timing of infection of roots and showed that infection occurred at day four and colonisation increased thereafter to high levels by 23 days after inoculation by which time roots were showing systemic abnormalities. To investigate the basis of this compatible interaction we have conducted a time course experiment following infection of a susceptible ecotype of Arabidopsis (Col-0) to examine whole genome geneexpression changes in the host. Differential gene expression analysis of inoculated versus control roots showed that a higher number of genes had altered expression levels at day four compared to that at day seven and at day ten. At day four the expression levels of several genes known to be important for recognition and signal transduction in resistant interactions and genes involved in the biosynthesis of lignin, phenylpropanoids and ethylene were suppressed. Suppression by P. brassicae of specific plant defence responses appears to be a key component of susceptibility in this system.

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Internationally, normative discourses about literacy standards have rapidly proliferated and spaces for teachers to engage in serious intellectual inquiry seem to be shutting down. What counts, in current times, is increasingly only what can be counted. The onslaught of political and media attacks about standards has left many teachers with low morale and low energy. Many experienced teachers are doubting their own wisdom, despite years of successful practice; many novice teachers are wondering why they entered the profession.

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Globally, there has been enhanced media -and public interest in tall buildings following the terrorist attacks on the World Trade Centre in New York. In the Arab region, tall buildings have also become an important topic of debate. The Middle East is set to grow significantly over the next two decades. Soaring population and jobs growth will increase demands for the better use of residential and commercial office space. This is a vital issue for the growth in the economy of the region. The number of construction sites for tall buildings in the Arab world is staggering when compared to European developments. A statistical review of tall buildings has shown for example that the United Arab Emirates (UAE) by the year 2010 will outnumber UK and Germany together in the number of 30+ floors buildings by reaching (446 UAE) compared to [243 UK(130) + Germany(113)]. Today high buildings are considered flagship developments not only in the Arab World but also worldwide that play an important part in regeneration. Tall buildings are likely to continue to be relevant to the master planning of areas with good public transport access and capacity. A successful tall building must adhere to a set of clear urban design guidelines that affect the following areas: edges, use, public space, urban integration and environmental factors. This paper addresses this issue. The challenge for architects, urban designers, and planners in the Arab world is to provide the right type and quality of new space and new place that won't undermine the question of identity. The paper explores the nature of tall buildings in the Arab region and provides examples of the positive and negative transformation of the urban environments in a number of locales. The paper concludes by drawing some guidelines for future development of tall buildings in the Arab World.

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Understanding and managing information infrastructure (II) security risks is a priority to most organizations dealing with information technology and information warfare (IW) scenarios today (Libicki, 2000). Traditional security risk analysis (SRA) was well suited to these tasks within the paradigm of computer security, where the focus was on securing tangible items such as computing and communications equipment (NCS,1996; Cramer, 1998). With the growth of information interchange and reliance on information infrastructure, the ability to understand where vulnerabilities lie within an organization, regardless of size, has become extremely difficult (NIPC, 1996). To place a value on the information that is owned and used by an organization is virtually an impossible task. The suitability of risk analysis to assist in managing IW and information infrastructure-related security risks is unqualified, however studies have been undertaken to build frameworks and methodologies for modeling information warfare attacks (Molander, Riddile, & Wilson, 1996; Johnson, 1997; Hutchinson & Warren, 2001) which will assist greatly in applying risk analysis concepts and methodologies to the burgeoning information technology security paradigm, information warfare.

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Testing the integrational properties of visitor arrivals has important implications for policy, for if visitor arrivals are integrated of order one (nonstationary) then it implies that shocks to visitor arrivals are permanent. However, if visitor arrivals are found to be integrated or order zero (stationary) then this implies that shocks to visitor arrivals are temporary. In this paper we examine whether visitor arrivals to Australia are stationary or nonstationary, using the recently developed univariate and panel Lagrange multiplier tests, and the Im, Pesaran and Shin [Im, K.S., Pesaran, M.H., Shin, Y., 1997. Testing for Unit Roots in Heterogeneous Panels. Manuscript, Department of Applied Economics, University of Cambridge; Im, K.S., Pesaran, M.H., Shin, Y., 2003. Testing for Unit Roots in Heterogeneous Panels. Journal of Econometrics, 115, 53–74] panel t-test. Our exercise involves Australia’s 28 tourist source markets. Our main findings are: (1) that visitor arrivals to Australia from 28 tourist source markets are stationary, implying that any shock will have only a temporary effect and (2) the second structural break, which mainly coincides with the September 11 terrorist attacks and the Asian financial crisis, has slowed down the growth rate in visitor arrivals to Australia from 22 out of 28 (79%) of the tourism source markets.

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BGP (Border Gateway Protocol) is a fundamental component of the current Internet infrastructure. However, BGP is vulnerable to a variety of attacks, since it cannot ensure the authenticity of the path attributes announced by BGP routers. Despite several solutions have been proposed to address this vulnerability, none of them is operational in real-world due to their immense impact on original BGP. In this paper, we propose a Deployable Path Validation Authentication scheme, which can effectively validate the path of BGP. Through analysis and simulation we show that this scheme has little impact on the performance and memory usage for the original BGP, and can be adopted in practice as an operational approach.

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The vision of volunteer computing is to provide large scale computational infrastructure by using dynamic collections of donated desktop computers. There have been many works that highlighted the significant benefits of volunteer computing but little on the security and privacy threats associated with its exploitation. However, volunteer computing is vulnerable to a variety of attacks and presents numerous significant security threats to the stakeholders. This paper presents security and privacy threat taxonomy along with the security features developed to cope with such threats.

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Terrorist groups are currently using information and communication technologies (ICTs) to orchestrate their conventional physical attacks. More recently, terrorists have been developing a new form of capability within the cyber-arena to coordinate cyber-based attacks. This paper identifies that cyber-terrorism capabilities are an integral, imperative, yet under-researched component in establishing, and enhancing cyber-terrorism risk assessment models for SCADA systems. This paper is an extension of work previously published by Beggs and
Warren 2008, it presents a high level overview of a cyber-terrorism SCADA risk framework that has been adopted and validated by SCADA industry practitioners. The paper proposes a managerial framework which is designed to measure and protect SCADA systems from the threat of cyber-terrorism within Australia. The findings and results of an industry focus group are presented in support of the developed framework for SCADA industry adoption and acceptance.

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Security protocol analysis has been discussed for quite some time in the past few years. Although formal methods have been widely used to identify various vulnerabilities, mainly susceptibility to freshness attacks and impersonation, the arisen inconsistent data between principals and collusion attacks held by a group of dishonest principals have been largely ignored. Moreover, the previous methods focus on reasoning about certain security-related properties and detecting known attacks against secure message, whereas there have been insufficient efforts to handle the above hidden but powerful attacks. In this paper, we address these critical issues and prove the efficiency and intuitiveness of rule-based dependency models in defending a protocol against the attacks. This is able to provide a numerical estimation to measure he occurrence of these attacks. It will be useful in enhancing the current protocol analysis.

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Since the September 11, 2001 terrorist attacks in New York City, many countries including Australia and Malaysia have been able to justify the use biometric devices such as fingerprint scans, retina scans and facial recognition for identification and surveillance of its citizens and others in the name of national security. In addition, biometric devices are increasingly being used worldwide by organizations to keep track of their employees and their productivity, leading to concerns of privacy and civil rights violations. Taking the critical theory perspective, this paper will analyse the data collected and report on the findings of a survey carried out in Australia and Malaysia, with respect to the responses provided and opinions expressed to the survey's open ended and other questions by individuals as to their current use, experiences, preferences, concerns about the devices and the situations in which they think biometric devices should be used, including in their workplaces. This descriptive study uses both quantitative and qualitative data to examine what Australians and Malaysians think about the use of biometric devices in everyday situations and compare them as to their similarities and differences within the context of each nation's culture and political systems. The paper will then critically examine the ethical and civil rights issues involved in the use of biometric devices in everyday life and what regulatory and legal measures should be taken to safeguard the rights of citizens while maintaining security and productivity, in order to avoid the situation of Michel Foucault's Panopticon becoming an unpleasant everyday reality, which could negatively influence social justice and create social change due to its effects on individuals in two multicultural societies. the apper will argue about the need to educate the general public as to the issues of surveillance and privacy involved in the use of biometric devices in everyday situations.

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Summary: "In the wake of the September 11 and subsequent terrorist attacks, the academic and media commentaries on Islam the religion and Islam the basis for political ideology haves received an unprecedented high level of exposure and attention. The acts of political violence by extremist groups and the omnipresent war on terror have added fresh uncertainties to an already complex global order. Just as terrorism and counter-terrorism are locked in a mutually re-enforcing symbiosis, the sense of insecurity felt by Muslims and non-Muslims alike is mutually dependent and has the potential to escalate. This general assessment holds true for Muslims living in the Muslim world and beyond. The pervasive sense of being under attack physically and culturally by the United States and its allies has contributed to a growing unease among Muslims and re-enforced deep-seated mistrust of the ʻWestʼ. Public articulation of such misgivings has in turn, lent credence to Western observers who posit an inherent antipathy between the West and the Muslim world. The subsequent policies that have emerged in this context of fear and mutual distrust have contributed to the vicious cycle of insecurity. The present volume is anchored in the current debates on the uneasy and potentially mutually destructive relationship between the Muslim world and certain West countries. It brings together leading international scholars in this interdisciplinary field to deal with such inter-related questions as the nature of Islamism, the impact of the ʻwar on terrorʼ on the spread of militancy, the growing sense of being under siege by Muslim Diasporas and the many unintended ramifications of a security-minded world order. This volume deliberately focuses on these issues both at a broad theoretical level but more importantly in the form of a number of prominent case studies including Indonesia, Algeria and Turkey."--Publisher description.

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When the Institute of International Education reported a drop of 2.4% in international student enrollment in the United States in 2003/2004, the first absolute decline in foreign enrollments since 1971/1972 (Open Doors, 2004), many were quick to point fingers at visa policies instituted after the September 11, 2001 attacks. The "Visas Mantis" review—a security clearance required for foreign students studying any of roughly 200 scientific fields—was blamed for tarnishing the view of the United States as a welcoming place for international students. Although the review has certainly been the cause of increased visa delays and rejections, this article takes the view that it is not the only cause for the dip in foreign enrollments in the United States. Through econometric analyses, it is shown that other than the visa quagmires, improved access to domestic education opportunities and tuition fee increases can indeed explain the drop in foreign enrollments.

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Wireless broadcasting is an efficient way to broadcast data to a large number of users. Some commercial applications of wireless broadcasting, such as satellite pay-TV, desire that only those users who have paid for the service can retrieve broadcast data. This is often achieved by broadcast encryption, which allows a station securely to broadcast data to a dynamically changing set of privileged users through open air. Most existing broadcast encryption schemes can only revoke a pre-specified number of users before system re-setup or require high computation, communication and storage overheads in receivers. In this paper, we propose a new broadcast encryption scheme based on smart cards. In our scheme, smart cards are used to prevent users from leaking secret keys. Additionally, once an illegally cloned smart card is captured, our scheme also allows tracing of the compromised smart card by which illegal smart cards are cloned, and can then revoke all cloned smart cards. The new features of our scheme include minimal computation needs of only a few modular multiplications in the smart card, and the capability to revoke up to any number of users in one revocation. Furthermore, our scheme is secure against both passive and active attacks and has better performance than other schemes.

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This paper examines the emergent security risk that information warfare poses to critical infrastructure systems, particularly as governments are increasingly concerned with protecting these assets against attack or disruption. Initially it outlines critical infrastructure systems and the notion of information warfare. It then discusses the potential implications and examining the concerns and vulnerabilities such cyber attacks would pose, utilising exemplar online attack occurrences. It then examines the current Australian situation before suggesting some considerations to mitigate the potential risk that information warfare poses to critical infrastructure systems, and by association: government, industry and the wider community.

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Through an investigation of the idea of the stranger, this article seeks to blend theory with empirical research. It does this in three ways. First, it engages with a social theory of the stranger articulated in the work of Zygmunt Bauman. Second, it examines data from the Australian Election Study surveys between 1996 and 2007 in order to explore attitudinal changes towards groups of immigrants. The findings from this survey suggests that attitudes towards immigrants in general have fluctuated in Australia, despite the negative effects of economic globalization, the growth in neoliberal economic reforms and terrorist attacks in the West. Third, drawing on Bauman's theory of the stranger we provide an interpretation of these fluctuating attitudes through the idea of the hybrid stranger. Finally, we argue that a more nuanced understanding of these attitudes towards immigrants in Australia is possible when a theory of the stranger is informed by a discussion on the constitution of host self, the influence of the media, the role of government policy, and the impact of class and geography.