O presente trabalho tem como objetivo analisar como os atentados de 11 de setembro de 2001 foram representados em uma série de histórias em quadrinhos (HQs) do Capitão América, escrita por John Ney Rieber e desenhada por John Cassaday, publicadas entre junho e dezembro de 2002, nos EUA. Essas HQs dialogam com diversos problemas que incomodavam a sociedade norte-americana no período pós-atentados como, por exemplo, os sentimentos de medo, insegurança, vingança e a recém-lançada Guerra ao Terror. Estes são discutidos e interpretados, partindo de dois pontos de vista diferentes, o do Capitão América e o dos terroristas, ou seja, as HQs procuraram expor as justificativas dos dois lados envolvidos. Elas expõem diversas críticas às ações bélicas dos Estados Unidos e também dos terroristas e têm um forte caráter pacifista. Além disso, divulgam uma mensagem de esperança pautada nas ideias do Sonho Americano, que deve ser entendido como uma força de união e mobilização nacional, visando à superação de todos os problemas causados pelos atentados de 11 de setembro / This study aims to analyze how the attacks of September 11, 2001 were represented in a series of Captain America comics, written by John Ney Rieber and drawn by John Cassaday, published between June and December 2002 in USA. These comics dialogue with various problems that bothered the American society in the post-attack period, for example, the feelings of fear, insecurity, revenge and the newly launched War on Terror. These are discussed and interpreted, from two different points of view, that of Captain America and the terrorists, in other words, the comics sought to expose the reasons on both sides involved. They expose several criticisms of the military actions of the United States and also the terrorists and have a strong pacifist character. Moreover, disseminate a message of hope ruled by ideas of the American Dream, which must be understood as a force for unity and national mobilization, aimed at overcoming all the problems caused by the September 11 attacks

Denial of service attacks (DoS) are a common threat to many online services. These attacks aim to overcome the availability of an online service with massive traffic from multiple sources. By spoofing legitimate users, an attacker floods a target system with a high quantity of packets or connections to crash its network resources, bandwidth, equipment, or servers. Packet filtering methods are the most known way to prevent these attacks via identifying and blocking the spoofed attack from reaching its target. In this project, the extent of the DoS attacks problem and attempts to prevent it are explored. The attacks categories and existing countermeasures based on preventing, detecting, and responding are reviewed. Henceforward, a neural network learning algorithms and statistical analysis are utilized into the designing of our proposed packet filtering system.

The World Trade Center attacks on September 11, 2001 fundamentally transformed the context of reception for Muslim immigrants in the U.S., shifting it from neutral to negative while also brightening previously blurred boundaries between established residents and the Muslim minority. This study explores how second-generation Muslim immigrants have experienced and reacted to post-9/11 contexts of reception. It is based on an analysis of ten semi-structured in-depth interviews that were conducted throughout the Portland Metropolitan Area from January to April of 2016. It finds experiences of discrimination to be primarily affected by two factors: public institutions and gender. It also finds, furthermore, that research participants react to negative post-9/11 contexts of reception by redrawing bright boundaries to include themselves within the American mainstream. Because Islam itself has become politicized within post-9/11 contexts of reception, this study also explores how second-generation Muslim immigrants construct and maintain religious meaning as a form of political identity. It finds that research participants unilaterally construct a Localized Islam that is dynamic and variable in its response to familial and social pressures. The thesis concludes by putting forward a typology outlining its four primary forms of localization within contemporary social and political environments.

<p><i>Objectives.</i> To study the prevalence of musculoskeletal symptoms among farmers as compared to rural referents and to evaluate the effects of physical work exposures, psychosocial factors, lifestyle and comorbidity.</p><p><i>Material and methods.</i> A cross-sectional population-based survey of 1013 farmers and 769 matched referents was performed. Data on various symptoms, consultations and sick leave and information on primary health care and hospital admissions were obtained along with information on physical workload, psychosocial factors and lifestyle. </p><p><i>Results.</i> The farmers reported higher lifetime prevalence of symptoms from hands and forearms, low back and hips as compared to the referents. However, the farmers did not seek medical advice more often than the referents, and they reported significantly fewer sick leaves. After adjustment for the influence of physical work exposure, farmers still had a excess rate of low back pain (LBP) and hip symptoms as compared with the referents, while a lower rate of neck-shoulder symptoms was revealed. Several of the psychosocial variables were associated with LBP but the difference in LBP prevalence between farmers and referents could only be explained to some extent. LBP was associated with musculoskeletal symptoms other than LBP and with chest discomfort, dyspepsia, symptoms from mucous membranes, skin problems, work-related fever attacks, and primary care for digestive disorders. Presence of both respiratory and digestive disorders doubled the LBP prevalence.</p><p><i>Conclusions.</i> Symptoms from hips and low back were more frequent among farmers than among referents, but farmers did not seek more health care and reported fewer sick leaves than referents. Physical work exposure and psychosocial factors did not explain the differences in low back and hip symptoms between the two groups. Significant associations between LBP and digestive and respiratory disorders might indicate that these disorders may have etiological factors in common.</p>

Objectives. To study the prevalence of musculoskeletal symptoms among farmers as compared to rural referents and to evaluate the effects of physical work exposures, psychosocial factors, lifestyle and comorbidity. Material and methods. A cross-sectional population-based survey of 1013 farmers and 769 matched referents was performed. Data on various symptoms, consultations and sick leave and information on primary health care and hospital admissions were obtained along with information on physical workload, psychosocial factors and lifestyle. Results. The farmers reported higher lifetime prevalence of symptoms from hands and forearms, low back and hips as compared to the referents. However, the farmers did not seek medical advice more often than the referents, and they reported significantly fewer sick leaves. After adjustment for the influence of physical work exposure, farmers still had a excess rate of low back pain (LBP) and hip symptoms as compared with the referents, while a lower rate of neck-shoulder symptoms was revealed. Several of the psychosocial variables were associated with LBP but the difference in LBP prevalence between farmers and referents could only be explained to some extent. LBP was associated with musculoskeletal symptoms other than LBP and with chest discomfort, dyspepsia, symptoms from mucous membranes, skin problems, work-related fever attacks, and primary care for digestive disorders. Presence of both respiratory and digestive disorders doubled the LBP prevalence. Conclusions. Symptoms from hips and low back were more frequent among farmers than among referents, but farmers did not seek more health care and reported fewer sick leaves than referents. Physical work exposure and psychosocial factors did not explain the differences in low back and hip symptoms between the two groups. Significant associations between LBP and digestive and respiratory disorders might indicate that these disorders may have etiological factors in common.

The objective of this thesis is to analyze whether the EU can be considered as a &lsquo / limited&rsquo / military/strategic actor or as a civilian actor in the Post-Cold War international security architecture. In this framework, the impacts of the September 11 terrorist attacks and the US-led war in Iraq on the EU crisis management capabilities are analyzed more specifically. In this framework, firstly, the historical dynamics of European foreign and security policy from the Post-World War II period to the Post-September 11 period are analyzed. Secondly, the EU&rsquo / s changing role in the international arena together with its crisis management capability is evaluated. Thirdly, the EU&rsquo / s international actorness in the Post-September 11 era is discussed with a special reference to the US-led war in Iraq. In this general framework, following a brief analysis on reactions of the US and the EU against global terrorism, crisis management strategy of the EU during and after US-led war in Iraq is analyzed in detail. The last part allocated to, a critical analysis of the security actorness of the EU is made in order to conceptualize it and to draw a more theoretical framework. Moreover, it is mentioned in this thesis that while having triggering effect on the CFSP and ESDP, the 9/11 events and the US-led war in Iraq provides the emergence of new methods for crisis management and the European Security Strategy. Accordingly, considering the new international security context beginning with the end of Cold War period and transforming to another dimension by means of September 11 attacks, the main argument of this thesis is that the EU still tends to be a civilian actor as it was before and it is envisaged to be so in the foreseeable future despite its latest attempts to develop its common security and defence policies.

<p>In today’s society, serious organizations need protection against both internal and external attacks. There are many different technologies available that organizations can incorporate into their organization in order to enhance security for their networking applications. Unfortunately, security is way to often considered as an afterthought and therefore implemented as an external part of the applications. This is usually performed by introducing general security models and technologies.</p><p>However, an already developed, well structured and considered security approach – with proper implementation of security services and mechanisms – different security models can be used to apply security</p><p>within the security perimeter of an organization. It can range from built into the application to the edge of a private network, e.g. an appliance. No matter the choice, the involved people must possess security expertise to deploy the proposed security models in this paper, that have the soul purpose to secure applications.</p><p>By using the Recommendation X.800 as a comparison framework, the proposed models will be analyzed in detail and evaluated of how they provide the security services concerned in X.800. By reasoning about what security services that ought to be implemented in order to prevent or detect diverse security attacks, the organization needs to carry out a security plan and have a common understanding of the defined security policies.</p><p>An interesting finding during our work was that, using a methodology that leads to low KLOC-values results in high security, though low KLOC-values and high security go hand-in-hand.</p>

The continuous growth of traffic demand driven by the brisk increase in number of Internet users and emerging online services creates new challenges for communication networks. The latest advances in Wavelength Division Multiplexing (WDM) technology make it possible to build Transparent Optical Networks (TONs) which are expected to be able to satisfy this rapidly growing capacity demand. Moreover, with the ability of TONs to transparently carry the optical signal from source to destination, electronic processing of the tremendous amount of data can be avoided and optical-to-electrical-to-optical (O/E/O) conversion at intermediate nodes can be eliminated. Consequently, transparent WDM networks consume relatively low power, compared to their electronic-based IP network counterpart. Furthermore, TONs bring also additional benefits in terms of bit rate, signal format, and protocol transparency. However, the absence of O/E/O processing at intermediate nodes in TONs has also some drawbacks. Without regeneration, the quality of the optical signal transmitted from a source to a destination might be degraded due to the effect of physical-layer impairments induced by the transmission through optical fibers and network components. For this reason, routing approaches specifically tailored to account for the effect of physical-layer impairments are needed to avoid setting up connections that don’t satisfy required signal quality at the receiver. Transparency also makes TONs highly vulnerable to deliberate physical-layer attacks. Malicious attacking signals can cause a severe impact on the traffic and for this reason proactive mechanisms, e.g., network design strategies, able to limit their effect are required. Finally, even though energy consumption of transparent WDM networks is lower than in the case of networks processing the traffic at the nodes in the electronic domain, they have the potential to consume even less power. This can be accomplished by targeting the inefficiencies of the current provisioning strategies applied in WDM networks. The work in this thesis addresses the three important aspects mentioned above. In particular, this thesis focuses on routing and wavelength assignment (RWA) strategies specifically devised to target: (i) the lightpath transmission quality, (ii) the network security (i.e., in terms of vulnerability to physical-layer attacks), and (iii) the reduction of the network energy consumption. Our contributions are summarized below. A number of Impairment Constraint Based Routing (ICBR) algorithms have been proposed in the literature to consider physical-layer impairments during the connection provisioning phase. Their objective is to prevent the selection of optical connections (referred to as lightpaths) with poor signal quality. These ICBR approaches always assign each connection request the least impaired lightpath and support only a single threshold of transmission quality, used for all connection requests. However, next generation networks are expected to support a variety of services with disparate requirements for transmission quality. To address this issue, in this thesis we propose an ICBR algorithm supporting differentiation of services at the Bit Error Rate (BER) level, referred to as ICBR-Diff. Our approach takes into account the effect of physical-layer impairments during the connection provisioning phase where various BER thresholds are considered for accepting/blocking connection requests, depending on the signal quality requirements of the connection requests. We tested the proposed ICBR-Diff approach in different network scenarios, including also a fiber heterogeneity. It is shown that it can achieve a significant improvement of network performance in terms of connection blocking, compared to previously published non-differentiated RWA and ICBR algorithms.  Another important challenge to be considered in TONs is their vulnerability to physical-layer attacks. Deliberate attacking signals, e.g., high-power jamming, can cause severe service disruption or even service denial, due to their ability to propagate in the network. Detecting and locating the source of such attacks is difficult, since monitoring must be done in the optical domain, and it is also very expensive. Several attack-aware RWA algorithms have been proposed in the literature to proactively reduce the disruption caused by high-power jamming attacks. However, even with attack-aware network planning mechanisms, the uncontrollable propagation of the attack still remains an issue. To address this problem, we propose the use of power equalizers inside the network nodes in order to limit the propagation of high-power jamming attacks. Because of the high cost of such equipment, we develop a series of heuristics (incl. Greedy Randomized Adaptive Search Procedure (GRASP)) aiming at minimizing the number of power equalizers needed to reduce the network attack vulnerability to a desired level by optimizing the location of the equalizers. Our simulation results show that the equalizer placement obtained by the proposed GRASP approach allows for 50% reduction of the sites with the power equalizers while offering the same level of attack propagation limitation as it is possible to achieve with all nodes having this additional equipment installed. In turn, this potentially yields a significant cost saving.    Energy consumption in TONs has been the target of several studies focusing on the energy-aware and survivable network design problem for both dedicated and shared path protection. However, survivability and energy efficiency in a dynamic provisioning scenario has not been addressed. To fill this gap, in this thesis we focus on the power consumption of survivable WDM network with dynamically provisioned 1:1 dedicated path protected connections. We first investigate the potential energy savings that are achievable by setting all unused protection resources into a lower-power, stand-by state (or sleep mode) during normal network operations. It is shown that in this way the network power consumption can be significantly reduced. Thus, to optimize the energy savings, we propose and evaluate a series of energy-efficient strategies, specifically tailored around the sleep mode functionality. The performance evaluation results reveal the existence of a trade-off between energy saving and connection blocking. Nonetheless, they also show that with the right provisioning strategy it is possible to save a considerable amount of energy with a negligible impact on the connection blocking probability. In order to evaluate the performance of our proposed ICBR-Diff and energy-aware RWA algorithms, we develop two custom-made discrete-event simulators. In addition, the Matlab program of GRASP approach for power equalization placement problem is implemented. / <p>QC 20120508</p>

Current Security Information and Event Management systems (SIEMs) constitute the central platform of modern security operating centers. They gather events from various sensors (intrusion detection systems, anti-virus, firewalls, etc.), correlate these events, and deliver synthetic views for threat handling and security reporting. Research in SIEM technologies has traditionally focused on providing a comprehensive interpretation of threats, in particular to evaluate their importance and prioritize responses accordingly. However, in many cases, threat responses still require humans to carry out the analysis and decision tasks e.g., understanding the threats, defining the appropriate countermeasures and deploying them. This is a slow and costly process, requiring a high level of expertise, and remaining error-prone nonetheless. Thus, recent research in SIEM technology has focused on the ability to automate the process of selecting and deploying countermeasures. Several authors have proposed automatic response mechanisms, such as the adaptation of security policies, to overcome the limitations of static or manual response. Although these approaches improve the reaction process (making it faster and/or more efficient), they remain limited since these solutions do not analyze the impact of the countermeasures selected to mitigate the attacks. In this thesis, we propose a novel and systematic process to select the optimal countermeasure from a pool of candidates, by ranking them based on a trade-off between their efficiency in stopping the attack and their ability to preserve, at the same time, the best service to normal users. In addition, we propose a model to represent graphically attacks and countermeasures, so as to determine the volume of each element in a scenario of multiple attacks. The coordinates of each element are derived from a URI. This latter is mainly composed of three axes: user, channel, and resource. We use the CARVER methodology to give an appropriate weight to each element composing the axes in our coordinate system. This approach allows us to connect the volumes with the risks (i.e. big volumes are equivalent to high risk, whereas small volumes are equivalent to low risk). Two concepts are considered while comparing two or more risk volumes: Residual risk, which results when the risk volume is higher than the countermeasure volume; and Collateral damage, which results when the countermeasure volume is higher than the risk volume. As a result, we are able to evaluate countermeasures for single and multiple attack scenarios, making it possible to select the countermeasure or group of countermeasures that provides the highest benefit to the organization

Cryptographic hash functions are an important tool in cryptography to achieve certain security goals such as authenticity, digital signatures, digital time stamping, and entity authentication. They are also strongly related to other important cryptographic tools such as block ciphers and pseudorandom functions. The standard and widely used hash functions such as MD5 and SHA-1 follow the design principle of Merkle-Damgard iterated hash function construction which was presented independently by Ivan Damgard and Ralph Merkle at Crypto'89. It has been established that neither these hash functions nor the Merkle-Damgard construction itself meet certain security requirements. This thesis aims to study the attacks on this popular construction and propose schemes that offer more resistance against these attacks as well as investigating alternative approaches to the Merkle-Damgard style of designing hash functions. This thesis aims at analysing the security of the standard hash function Cellular Authentication and Voice Encryption Algorithm (CAVE) used for authentication and key-derivation in the second generation (2G) North American IS-41 mobile phone system. In addition, this thesis studies the analysis issues of message authentication codes (MACs) designed using hash functions. With the aim to propose some efficient and secure MAC schemes based on hash functions. This thesis works on three aspects of hash functions: design, cryptanalysis and applications with the following significant contributions: * Proposes a family of variants to the Damgard-Merkle construction called 3CG for better protection against specific and generic attacks. Analysis of the linear variant of 3CG called 3C is presented including its resistance to some of the known attacks on hash functions. * Improves the known cryptanalytical techniques to attack 3C and some other similar designs including a linear variant of GOST, a Russian standard hash function. * Proposes a completely novel approach called Iterated Halving, alternative to the standard block iterated hash function construction. * Analyses provably secure HMAC and NMAC message authentication codes (MACs) based on weaker assumptions than stated in their proofs of security. Proposes an efficient variant for NMAC called NMAC-1 to authenticate short messages. Proposes a variant for NMAC called M-NMAC which offers better protection against the complete key-recovery attacks than NMAC. As well it is shown that M-NMAC with hash functions also resists side-channel attacks against which HMAC and NMAC are vulnerable. Proposes a new MAC scheme called O-NMAC based on hash functions using just one secret key. * Improves the open cryptanalysis of the CAVE algorithm. * Analyses the security and legal implications of the latest collision attacks on the widely used MD5 and SHA-1 hash functions.