DFBotKiller: Domain-flux botnet detection based on the history of group activities and failures in DNS traffic

Each botnet needs an addressing mechanism to locate its command and control (C&C) server(s). This mechanism allows a botmaster to send commands to and receive stolen data from compromised hosts. To maximize the availability of the C&C server(s), botmasters have recently started to use domain-flux techniques. However, domain-flux botnets have some important characteristics that we can use to detect them. They usually generate a large number of DNS queries resolved to the same IP address and they often generate many failures in DNS traffic. The domain names in the DNS queries are randomly or algorithmically generated and their alphanumeric distribution is significantly different from legitimate ones. In this paper, we present DFBotKiller, a negative reputation system that considers the history of both suspicious group activities and suspicious failures in DNS traffic to detect domain-flux botnets. Our main goal is to automatically assign a high negative reputation score to each host that is involved in these suspicious domain activities. To identify randomly or algorithmically generated domain names, we use three measures, namely the Jensen-Shannon divergence, Spearman's rank correlation coefficient, and Levenshtein distance. We demonstrate the effectiveness of DFBotKiller to detect hosts infected by domain-flux botnets using multiple DNS queries collected from our campus network and a testbed network consisting of some bot-infected hosts. The experimental results show that DFBotKiller can make a good trade-off between the detection and false alarm rates.     

基本养老保险制度对企业年金的规制作用

基本养老保险和企业年金是一对互动的因子,基本养老保险处于主导地位,企业年金是有益的补充.基本养老保险的价值目标、制度安排、替代水平、财务状况和覆盖范围影响和制约着企业年金的性质、地位及发展的方向、空间、需求和规模.双因子的权变组合不仅构成了养老保险制度建设的基本内容,而且制约着养老保险的保障水平和发展方向.     

Are There Negative Returns to Aid?

The World Bank report Assessing Aid assumes that an inflow of aid, above a certain level, starts to have negative effects. In this analysis we empirically test this assumption. We find evidence for negative returns to aid at high levels of aid inflows. However, the results are sensitive to both the countries included in the sample and model specification. Moreover, the turning-point above which aid starts to have a negative effect on growth seems to be much higher than assumed in the background calculations for Assessing Aid.     

冷战后东盟对西方人权压力的反应及其影响

冷战结束后,以美国为主的西方社会不再对东南亚进行直接的军事干涉,而是增加了以人权为借口和手段对东盟施加的压力。面对西方压力,东盟在不同阶段作出了不尽相同的反应。在东盟与西方博弈以及走向一体化的过程中,人权逐渐演变为东盟的重要议题之一,已经并将继续对东盟的发展产生一些不可忽视的影响。     

西方警察亚文化研究述评

警察亚文化是西方警察科学研究的重要组成部分,西方学者从社会学角度进行的警察亚文化研究具有积极和消极方面的影响。应当从批判的视角述评西方警察亚文化研究,目的是认清其精华与糟粕,以供我国的警察文化研究借鉴利用,进而有利于我国和谐警察文化建设。     

大学生不良亚文化现象及其应对措施

大学生不良亚文化现象主是由社会不良环境、高校教育的弊端、家庭教育的缺失和大学生自身因素共同作用产生的后果，对大学生产生了诸多负面影响。因此，我们需对症下药，从社会、高校、家庭和大学生自身的角度出发，通过大力宣扬中华民族优秀传统文化，加强对文化市场的监督与管理，优化家庭环境等措施，减少乃至消除大学生不良亚文化现象带来的严重危害。     

Exploring the Consequences of Negative Political Advertising for Liberal Democracy

ABSTRACT

This paper explores existing thinking and research on the use of negative advertising strategies in political campaigning, and in particular examines their potential impact on liberal democracy. We ask what impacts negative forms of political communication may have on our system of government and democratic participation. Though political advertising makes up only a part of political discourse, an analysis of it is necessary given the increasing “marketisation” of political communication, coupled with concerns regarding the so called “democratic deficit.” In order to more truly evaluate its impact, the evidence pertaining to both the positive and detrimental consequences of employing negative ad strategies is examined. What emerges are some very real short-term benefits, some very real concerns over its use, and confusion over its “true” impact. Of particular note is the need for researchers and campaign managers to take a longer-term view of the potentially detrimental consequences of employing negative advertising strategies-to look beyond the short-term gains of winning elections and to consider the longer-term societal consequences of consistently employing advertising strategies characterised by the creation of doubt, fear, anxiety, violation and viciousness. We argue that the “winning” mentality of political ad campaigns needs to be balanced by a more “nurturing” orientation if the tenets of liberal democracy are to remain sustainable.     

The Impact of Negative Forensic Evidence on Mock Jurors’ Perceptions of a Trial of Drug-Facilitated Sexual Assault

Legal concerns with regard to the adverse impact of a negative toxicological screening for date-rape drugs in a case of drug-facilitated sexual assault (DFSA) were the focus of a recent Canadian case (R. v. Alouache, 2003). To assess the impact of a negative forensic report, as well as the impact of expert testimony explaining the many factors that may contribute to a negative outcome, participants (N=171) received a written trial stimulus in which the forensic evidence (negative report, negative report plus expert testimony, no negative report and no expert testimony control) and the complainant's beverage consumption (alcohol, cola) were systematically varied. Results indicate that a negative finding in the absence of expert testimony produced greater verdict leniency and more favourable evaluations of the defendant's case. In contrast, no differences were found between the case in which the expert testified and a case in which the negative report and expert testimony were omitted.

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Family Psychopathology and Perceived Stress of Both Domestic Violence and Negative Life Events as Predictors of Women’s Mental Health Symptoms

Using a diathesis–stress model, this study examined the development of depressive and anxiety symptoms in women who experience stressors of domestic violence (DV) and/or negative life events (NLEs) over the course of three years. Family history of affective mental health problems represented the diathesis. Using a person-oriented approach, 182 women were grouped into 6 risk profiles based on varying levels of DV and NLEs. Results showed that family history of psychopathology increased vulnerability to mental health disorders; however, the best predictor of symptoms was the presence of either stressor at any time. A quadratic relationship between the risk pattern and mental health symptoms indicated that fluctuations in depression were related to the pattern of stress experienced. Results support the diathesis–stress model for occurrence of depressive but not anxiety symptoms in women with DV and/or NLEs.     

浅谈网络对大学生的负面影响及相关对策

随着“网络时代”的到来 ,电脑网络已经成为大学生进行社会交往、消度闲暇时间的新一维空间。但是计算机网络在给人类带来益处的同时 ,也对大学生的成长造成了一些消极影响 ,主要表现在容易消解社会主义的意识形态和民族优秀文化 ,弱化青少年的道德意识 ,使大学生的处世态度趋向消极 ,诱发青年大学生的破坏欲望。这些问题应引起我们的高度警惕和重视