The Effects of Terrorism on Turkish Financial Markets

Abstract

In this research, we analyzed how Turkish financial markets and foreign investors in the stock market reacted to the terror attacks in Turkey. Our analysis, which was performed using the terror index for the stock market and the foreign exchange market, revealed that returns, abnormal returns, and cumulative abnormal returns were not affected by the terror attacks; however, foreign investors in the stock market were affected. When the geographic regions of the terror attacks were analyzed, the findings showed that foreign investors were negatively affected mainly by the terror attacks that occurred in southeast Anatolia. Attack type and target type were important only for foreign investors. An evaluation of the interaction between the terror attacks and the markets with the involvement of the terrorist organizations indicated that only the foreign investors in the stock market were affected by Al-Qaeda and PKK-linked terror attacks. An evaluation of the effect of terror attacks in foreign countries on Turkish financial markets revealed no effect on the domestic stock market and foreign exchange markets. We also examined the volatility spillovers from the terror index to the stock market and found that terrorist attacks increased the volatility of the stock market.     

African nations as proxies in covert cyber operations

The growth of the African Internet, and services related to the Internet, has been rapid over the last decade. Following this market expansion, a variety of service providers have started to provide access. A fast-growing market puts pressure on the providers to deliver services first and only then seek to secure the networks. Over time, industrialised nations have become more able to detect and trace cyber attacks against their networks. These tracking features are constantly developing and the precision in determining the origin of an attack is increasing. A state-sponsored cyber attacker, such as intelligence agencies and electronic warfare units, will seek to avoid detection, especially when the attacks are politically sensitive intelligence-gathering and intrusion forays into foreign states' networks. One way for the attacker to create a path that links the attacks and the originating country is by actions through a proxy. The less technologically mature developing nations offer an opportunity for cyber aggression due to their lower level of security under the quick expansion of the Internet-based market. Developing countries could be used as proxies, without their knowledge and consent, through the unauthorised usage of these countries' information systems in an attempt to attack a third country by a state-sponsored offensive cyber operation. If the purpose of the cyber attack is to destabilise a targeted society and the attack succeeds, the used proxies are likely to face consequences in their relations with foreign countries, even if the proxy was unaware of the covert activity.     

八轮MISTY1算法的相关密钥扩大飞来去器攻击

密钥扩展算法对分组密码的安全至关重要,目前各种攻击方法越来越关注密钥带来的影响.通过分析非线性函数FI和密钥扩展算法,并观察轮子密钥的排列方式,寻找到MISTY1算法一个包含290个弱密钥的、可应用于相关密钥扩大飞来去器攻击的弱密钥类.在弱密钥类的基础上,寻找到两条相互独立的相关密钥差分路径,从而构造了一个七轮MISTY1算法的相关密钥扩大飞来去器区分器,进而实现了对八轮MISTY1算法(不带最后FL层)的相关密钥扩大飞来去器攻击.攻击需要263个选择明文,攻击的计算复杂度是270.该攻击是第一个对不带最后FL层MISTY1算法的八轮攻击,且与同类攻击方法相比,攻击算法放宽了所需要的相关密钥的限制条件.     

Weakest‐link attacker‐defender games with multiple attack technologies

In this article, we examine a model of terrorism that focuses on the tradeoffs facing a terrorist organization that has two qualitatively different attack modes at its disposal. The terrorist organization's objective is to successfully attack at least one target. Success for the target government is defined as defending all targets from any and all attacks. In this context, we examine how terrorist entities strategically utilize an efficient but discrete attack technology — e.g., suicide attacks — when a more conventional mode of attack is available, and the optimal anti‐terrorism measures.© 2012 Wiley Periodicals, Inc. Naval Research Logistics, 2012     

SHA-512算法及其基于生日攻击的安全性分析

生日攻击是一种通用的碰撞攻击方法,它可用于攻击任何类型的散列函数。分析了SHA-512的算法原理,讨论了生日攻击的碰撞阈值和攻击步骤,并对SHA-512算法在生日攻击下的安全性进行了分析。通过分析得出SHA-512所有消息块处理完后得到了8个64位变量H0-H7的数据级联,并且输出散列码是512位,这对于攻击者来说是不可预测的,猜中的概率可以忽略,而找到目标消息的碰撞的计算复杂度为2256。所以,相对来说SHA-512的安全性比MD5,SHA-1等要高,采用SHA-512后将更能抵抗生日攻击,并能抵御已知密码分析攻击。     

MD5的一种新的碰撞攻击

模差分分析是结合整数模减差分和XOR差分而定义的一种新的差分,与单一的模减差分或XOR差分相比,2种差分结合能表达更多的消息,从而可以更有效地分析、破解现有的哈希函数.MD5是哈希函数的一种,对消息的差分分析是对哈希函数实施碰撞攻击的重要手段,从目前已知的基于差分技术的攻击事实看,主要采用的是6比特差分和1比特差分.提...     

无线自组织网络跨层攻击检测博弈模型

无线自组织网络中的跨层攻击具有比单层攻击更强的隐蔽性、更好的攻击效果或更低的攻击成本.为了检测无线自组织网络中的跨层攻击,提出了一种基于博弈论的攻击检测模型.由于攻击不可避免地会对各协议层的参数造成影响,因此模型从协议层攻防博弈的角度,建立起相应的策略矩阵和支付矩阵,并通过均衡分析得到该模型的混合策略纳什均衡解.仿真结...     

Allocating capacity in parallel queues to improve their resilience to deliberate attack

We develop models that lend insight into how to design systems that enjoy economies of scale in their operating costs, when those systems will subsequently face disruptions from accidents, acts of nature, or an intentional attack from a well‐informed attacker. The systems are modeled as parallel M/M/1 queues, and the key question is how to allocate service capacity among the queues to make the system resilient to worst‐case disruptions. We formulate this problem as a three‐level sequential game of perfect information between a defender and a hypothetical attacker. The optimal allocation of service capacity to queues depends on the type of attack one is facing. We distinguish between deterministic incremental attacks, where some, but not all, of the capacity of each attacked queue is knocked out, and zero‐one random‐outcome (ZORO) attacks, where the outcome is random and either all capacity at an attacked queue is knocked out or none is. There are differences in the way one should design systems in the face of incremental or ZORO attacks. For incremental attacks it is best to concentrate capacity. For ZORO attacks the optimal allocation is more complex, typically, but not always, involving spreading the service capacity out somewhat among the servers. © 2011 Wiley Periodicals, Inc. Naval Research Logistics, 2011     

移动Ad Hoc网络中“虫洞”攻击分析及算法设计

阐述了＂虫洞＂攻击原理,建立了攻击模型和流程图,针对典型路由协议进行了＂虫洞＂攻击分析及算法设计,并用OPNET软件对＂虫洞＂攻击进行仿真。仿真结果初步验证了＂虫洞＂攻击对Ad Hoc网络的危害性。     

Military support and transnational terrorism

Analysing the relationship between the provision of military support and the probability of becoming the target of a terrorist attack, this paper contributes to the literature on the causes of transnational terrorism. We find that deployment of military troops of country X in country Y increases the probability of a terrorist attack on citizens of country X by a terrorist group located in country Y. Exporting weapons to country Y seems to increase the probability of being attacked by the terrorists of this country Y as well. Deploying materials, however, does not seem to significantly influence the probability of attack. Including lagged values for our military support variables ensures that the causality direction is from military support to terrorist attacks. Moreover, these results indicate that while the effect of military deployment on the probability of attack lasts for more than 1 year, the effect is rather short-lived.     

A cost–benefit analysis of terrorist attacks

A cost–benefit analysis of terrorist attacks is developed and placed within a systematic theoretical structure. For the target or object of the attack, we consider the lost value of human lives, lost economic value, and lost influence value, counted as benefits for the terrorist. The corresponding losses for the terrorist are counted as costs. The terrorist attacks if benefits outweigh costs. Bounded rationality is enabled where the three kinds of benefits and costs can be weighted differently. We account for two ex ante probabilities of successful planning and attack, and enable the terrorist to assign different weights to its multiple stakeholders. We introduce multiple time periods, time discounting, attitudes towards risk, and subcategories for the benefits and costs. The cost–benefit analysis is illustrated with the 11 September 2001 attack, and 53 incidents in the Global Terrorism Database yielding both positive and negative expected utilities. The paper is intended as a tool for scientists and policy-makers, as a way of thinking about costs and benefits of terrorist attacks.     

颠覆性技术发展面临的挑战与对策

信息攻防作战力量既可以独立成军成战,又可以和各军兵种、各种武器平台无缝衔接、联合协同,以发挥无限的战争潜力,是以信息攻防新技术为支撑、以软硬打击新能力为标志的新型作战力量。从核心信息基础设施建设,信息攻击和防护能力建设以及信息攻防协同作战三个方面论述了信息攻防新型作战力量建设的重要问题及战法对策,对信息攻防作战的特点规律和技术手段进行了剖析。     

一种无线传感器网络中的Sybil攻击检测方案

Sybil攻击破坏无线传感器网络中的数据融合、公平资源分配等机制，因此对Sybil攻击的防范与检测具有很重要的意义。将一种基于到达时间差（TDOA）的三维定位引入到Sybil攻击的检测中，算法可以检测存在的Sybil攻击并对Sybil节点进行定位。通过性能分析证明该算法具有开销小、有效性高的特点。     

Budgetary savings from conscription and burden sharing in NATO

We study the spatial and temporal determinants of terrorism risk in Israel, using a geocoded database of Israeli terrorist attacks from 1949 to 2004. In selecting targets, terrorists seem to respond rationally to costs and benefits: they are more likely to hit targets more accessible from their own homebases and international borders, closer to symbolic centers of government administration, and in more heavily Jewish areas. We also examine the waiting time between attacks experienced by localities. Long periods without an attack signal lower risk for most localities, but higher risk for important areas such as regional or national capitals.     

警报关联图：一种网络脆弱性量化评估的新方法

作为一种基于模型的脆弱性分析技术,攻击图能够识别网络中存在的脆弱性和它们之间的相互关系,分析出可能的攻击路径和潜在威胁.论文在攻击图的基础上提出了警报关联图的概念,利用攻击图中蕴含的脆弱性先验知识,将实时IDS警报信息映射到攻击路径,动态反映攻击进程和攻击者意图.在此基础上提出了一种基于警报关联图的网络脆弱性量化评估方法,通过计算警报关联边的权值对网络脆弱性进行动态分析,这种方法结合了静态的网络脆弱性先验知识和动态变化的攻击者意图,能有效反映网络脆弱性在动态攻击情况下的变化.     

防空体系反制网电攻击的UML与Petri网模型

网电攻击装备的出现,给传统防空体系带来全面严峻的新威胁。通过分析"舒特"系统,得到网电攻击3种典型作战样式:物理摧毁、电子攻击和网络攻击,分别从物理层次、能量层次和网络层次探索了防空体系反制网电攻击策略。为描述防空体系反制网电攻击的对策、作战结构、作战步骤等问题,分别建立了统一建模语言(UML)和Petri网模型,从理论上初步探索了防空体系反制网电攻击的对策,具有一定的理论与现实意义。     

Interdiction models for delaying adversarial attacks against critical information technology infrastructure

Information technology (IT) infrastructure relies on a globalized supply chain that is vulnerable to numerous risks from adversarial attacks. It is important to protect IT infrastructure from these dynamic, persistent risks by delaying adversarial exploits. In this paper, we propose max‐min interdiction models for critical infrastructure protection that prioritizes cost‐effective security mitigations to maximally delay adversarial attacks. We consider attacks originating from multiple adversaries, each of which aims to find a “critical path” through the attack surface to complete the corresponding attack as soon as possible. Decision‐makers can deploy mitigations to delay attack exploits, however, mitigation effectiveness is sometimes uncertain. We propose a stochastic model variant to address this uncertainty by incorporating random delay times. The proposed models can be reformulated as a nested max‐max problem using dualization. We propose a Lagrangian heuristic approach that decomposes the max‐max problem into a number of smaller subproblems, and updates upper and lower bounds to the original problem via subgradient optimization. We evaluate the perfect information solution value as an alternative method for updating the upper bound. Computational results demonstrate that the Lagrangian heuristic identifies near‐optimal solutions efficiently, which outperforms a general purpose mixed‐integer programming solver on medium and large instances.     

一种动态门限群签名方案的安全性分析

门限群签名是群签名的推广,其中只有授权子集才能代表整个群体进行签名。一旦发生纠纷,签名成员的身份可以被追查出来。指出一种动态门限群签名方案有冗余,提出了针对该签名三种攻击。分析结果证明该门限群签名方案不具有防冒充性,不能抵抗合谋攻击,门限的动态更新、群成员注销和系统密钥更新也不安全。     

Market reactions to regulations on minerals from the democratic republic of the Congo

Using an event study approach to analyze stock market data from the United States, I investigate how regulations on conflict minerals sourced in the Democratic Republic of the Congo were perceived by investors. I find that for a subset of mining companies, stock returns were abnormally high when regulations in the US became more likely. I also find that returns were higher for communications equipment manufacturing companies when strong regulations in the DRC were announced. I argue that these responses were due to the competitive environments faced by each of these company types. These findings relate to debates surrounding the effects of the conflict mineral regulations. While some critics argue that reporting requirements were tantamount to a ban on minerals from the DRC, I find that stock returns for a subset of companies were sensitive to legislation in the DRC after legislation became law in the US, suggesting that market participants did not expect a complete trade ban on regulated mining and trading activities.     

在线学习的主用户仿冒攻击策略

在认知无线网络中,次用户通过频谱感知来学习频谱环境,从而接入那些没有被主用户占用的频谱空隙。事实上,多种恶意攻击的存在会影响次用户频谱感知的可靠性。只有深入研究恶意攻击策略,才能确保认知无线网络的安全。基于此,研究了一种认知无线网络中的欺骗性干扰策略,即主用户仿冒攻击策略,该攻击策略通过在信道上传输伪造的主用户信号来降低次用户频谱感知的性能。具体来说,将攻击策略问题建模为在线学习问题,并提出基于汤普森采样的攻击策略以实现在探索不确定信道和利用高性能信道间的权衡。仿真结果表明,与现有的攻击策略相比,提出的攻击策略能更好地通过在线学习优化攻击决策以适应非平稳的认知无线网络。