Defending Against IoT-Enabled DDoS Attacks at Critical Vantage Points on the Internet

The number of Internet of Things (IoT) devices continues to grow every year. Unfortunately, with the rise of IoT devices, the Internet is also witnessing a rise in the number and scale of IoT-enabled distributed denial-of-service (DDoS) attacks. However, there is a lack of network-based solutions targeted directly for IoT networks to address the problem of IoT-enabled DDoS. Unlike most security approaches for IoT which focus on hardening device security through hardware and/or software modification, which in many cases is infeasible, we introduce network-based approaches for addressing IoT-enabled DDoS attacks. We argue that in order to effectively defend the Internet against IoT-enabled DDoS attacks, it is necessary to consider network-wide defense at critical vantage points on the Internet. This dissertation is focused on three inherently connected and complimentary components: (1) preventing IoT devices from being turned into DDoS bots by inspecting traffic towards IoT networks at an upstream ISP/IXP, (2) detecting DDoS traffic leaving an IoT network by inspecting traffic at its gateway, and (3) mitigating attacks as close to the devices in an IoT network originating DDoS traffic. To this end, we present three security solutions to address the three aforementioned components to defend against IoT-enabled DDoS attacks

Online Accumulation: Reconstruction of Worm Propagation Path

Abstract. Knowledge of the worm origin is necessary to forensic analysis, and knowledge of the initial causal flows supports diagnosis of how network defenses were breached. Fast and accurate online tracing network worm during its propagation, help to detect worm origin and the earliest infected nodes, and is essential for large-scale worm containment. This paper introduces the Accumulation Algorithm which can efficiently tracing worm origin and the initial propagation paths, and presents an improved online Accumulation Algorithm using sliding detection windows. We also analyzes and verifies their detection accuracy and containment efficacy through simulation experiments in large scale network. Results indicate that the online Accumulation Algorithm can accurately tracing worms and efficiently containing their propagation in an approximately real-time manner

Host parasite interactions in a cestode with a complex life cycle, Schistocephalus solidus

Many parasites have complex life cycles, i.e. they have to pass through several host species to reach maturity. Hence complex life cycles often consist of invertebrate and vertebrate hosts, the parasite likely varies in the machinery required for infection, exploitation and transmission of each host. Does the ability to optimally exploit one host inevitably lead to a reduced ability for the parasite to exploit another host in its life cycle? To answer this question, I analysed parasite life history traits like transmission, infection, and establishment in the model system of the tapeworm Schistocephalus solidus in relation to its two intermediate hosts, a cyclopoid copepod, and the three-spined stickleback. In this thesis, I particularly focus on interactions with the hosts' immune systems and on constraints, which are potentially shaping the evolution of virulence in parasites with complex life cycles

Six RNA Viruses and Forty-One Hosts: Viral Small RNAs and Modulation of Small RNA Repertoires in Vertebrate and Invertebrate Systems

We have used multiplexed high-throughput sequencing to characterize changes in small RNA populations that occur during viral infection in animal cells. Small RNA-based mechanisms such as RNA interference (RNAi) have been shown in plant and invertebrate systems to play a key role in host responses to viral infection. Although homologs of the key RNAi effector pathways are present in mammalian cells, and can launch an RNAi-mediated degradation of experimentally targeted mRNAs, any role for such responses in mammalian host-virus interactions remains to be characterized. Six different viruses were examined in 41 experimentally susceptible and resistant host systems. We identified virus-derived small RNAs (vsRNAs) from all six viruses, with total abundance varying from “vanishingly rare” (less than 0.1% of cellular small RNA) to highly abundant (comparable to abundant micro-RNAs “miRNAs”). In addition to the appearance of vsRNAs during infection, we saw a number of specific changes in host miRNA profiles. For several infection models investigated in more detail, the RNAi and Interferon pathways modulated the abundance of vsRNAs. We also found evidence for populations of vsRNAs that exist as duplexed siRNAs with zero to three nucleotide 3′ overhangs. Using populations of cells carrying a Hepatitis C replicon, we observed strand-selective loading of siRNAs onto Argonaute complexes. These experiments define vsRNAs as one possible component of the interplay between animal viruses and their hosts

Shrinking the Malaria Map: A Prospectus on Malaria Elimination

\ud Thirty-nine countries across the world are making progress toward malaria elimination. Some are committed to nationwide elimination, while others are pursuing spatially progressive elimination within their borders. Influential donor and multilateral organizations are supporting their goals of achieving malaria-free status. With elimination back on the global agenda, countries face a myriad of questions. Should they change their programs to eliminate rather than control malaria? What tools are available? What policies need to be put into place? How will they benefit from elimination? Unfortunately, answers to these questions, and resources for agencies and country program managers considering or pursuing elimination, are scarce. The 39 eliminating countries are all positioned along the endemic margins of the disease, yet they naturally experience a variety of country characteristics and epidemiologies that make their malaria situations different from one another. The Malaria Elimination Group (MEG) and this Prospectus recognize\ud that there is no single solution, strategy, or time line that will be appropriate for every country, and each is encouraged to initiate a comprehensive evaluation of its readiness and strategy for elimination. The Prospectus is designed to guide countries in conducting these assessments. The Prospectus provides detailed and informed discussion on the practical means of achieving and sustaining zero transmission. It is designed as a road map, providing direction and options from which to choose an appropriate path. As on all maps, the destination is clearly marked, but the possible routes to reach it are numerous. The Prospectus is divided into two sections: Section 1 Eliminating Malaria comprises four chapters covering the strategic components important to the periods before, during, and after an elimination program. Section 2 Tools for the Job, comprises six chapters that outline basic information about how interventions in an elimination program will be different from those in a control setting. Chapter 1, Making the Decision, evaluates the issues that a country should consider when deciding whether or not to eliminate malaria. The chapter begins with a discussion about the quantitative and qualitative benefits that a country could expect from eliminating malaria and then recommends a thorough feasibility assessment. The feasibility assessment is based on three major components: operational, technical, and financial feasibility. Cross-border and regional collaboration is a key subject in this chapter. Chapter 2, Getting to Zero, describes changes that programs must consider when moving from sustained control to an elimination goal. The key strategic issues that must be addressed are considered, including supply chains, surveillance systems, intersectoral collaboration, political will, and legislative framework. Cross-border collaboration is again a key component in Getting to Zero. Chapter 3, Holding the Line, provides recommendations on how to conduct an assessment of two key factors that will affect preventing the reemergence of malaria once transmission is interrupted: outbreak risk and importation risk. The chapter emphasizes the need for a strong surveillance system in order to prevent and, if necessary, respond to imported cases. Chapter 4, Financing Elimination, reviews the cost-effectiveness of elimination as compared with sustained control and then presents the costs of selected elimination programs as examples. It evaluates four innovative financing mechanisms that must support elimination, emphasizing the need for predictable and stable financing. Case studies from Swaziland and two provinces in China are provided. Chapter 5, Understanding Malaria, considers malaria from the point of view of elimination and provides a concise overview of the current burden of the disease, malaria transmission, and the available interventions that can be used in an elimination program. Chapter 6, Learning from History, extracts important lessons from the Global Malaria Eradication Program and analyzes some elimination efforts that were successful and some that were unsuccessful. The chapter also reviews how the malaria map has been shrinking since 1900. xiv A Prosp ectus on Mala ria Elimi natio n\ud Chapter 7, Measuring Malaria for Elimination, provides a precise language for discussing malaria and gives the elimination discussion a quantitative structure. The chapter also describes the role of epidemiological theory and mathematical modeling in defining and updating an elimination agenda for malaria. Chapter 8, Killing the Parasite, outlines the importance of case detection and management in an elimination setting. Options for diagnosis, the hidden challenge of Plasmodium vivax in an elimination setting, and the impact of immunity are all discussed. Chapter 9, Suppressing the Vector, explores vector control, a necessary element of any malaria program. It considers optimal methods available to interrupt transmission and discusses potential changes, such as insecticide resistance, that may affect elimination efforts. Chapter 10, Identifying the Gaps — What We Need to Know, reviews the gaps in our understanding of what is required for elimination. The chapter outlines a short-term research agenda with a focus on the operational needs that countries are facing today. The Prospectus reviews the operational, technical, and financial feasibility for those working on the front lines and considers whether, when, and how to eliminate malaria. A companion document, A Guide on Malaria Elimination for Policy Makers, is provided for those countries or agencies whose responsibility is primarily to make the policy decisions on whether to pursue or support a malaria elimination strategy. The Guide is available at www.malaria eliminationgroup.org

Trematode parasites of mollusc hosts from marginal seas and their sensitivity to warming

Parasites, like the diverse Digenean trematodes, are crucial to ecosystems, influencing everything from ecological speciation to food webs and host behavior. However, knowledge deficits persist regarding their biodiversity, life cycles, and geographical distribution, which complicates our broader understanding of ecosystems and response to the crisis in biodiversity. Some parasites risk extinction before they are discovered, especially in rapidly warming Marginal Seas such as the Persian Gulf and Baltic Sea, as a result of the ongoing global warming accelerated by human activity. Therefore, it is imperative to investigate the effects of warming on host-parasite systems in these regions and to comprehend the thermal performance of parasites. This is especially true as basic information such as parasite biodiversity is still missing in some regions, while the impact of environmental change on parasite performance remains largely unknown even in well-studied areas. Within four chapters, this thesis aimed to explore the yet unknown trematode biodiversity in the Persian and Oman Gulfs via molecular identification of trematodes infecting the most abundant mud snail Pirenella cingulata. Next, we investigate the thermal sensitivity of two prevalent trematodes (Acanthotrema tridactyla and Cyathocotylidae gen. sp) infecting P. cingulata. Lastly, this thesis investigates the combined effect of warming and parasitism on mussel performance using Renicola roscovita infecting Mytilus edulis as the host-parasite system in the Baltic Sea

A fishy tale: the impact of multiple stressors on host behaviour, physiology, and susceptibility to infectious disease

Aquatic habitats are facing increased anthropogenic stressors that are associated with multiple species demise. The loss of species is, sadly, part of a wider global crisis with current extinction levels estimated to be a thousand-fold higher than the background extinction rate. Freshwater habitats in particular are facing higher rates of degradation than any other habitat and within these, fish species are being lost faster than their terrestrial counterparts. Beyond the importance of fish as keystone species, they are an invaluable source of protein for humanity and stocks are facing a state of collapse. A key threat facing the fish industry, including wild stocks, is increased infectious disease burdens. A major reason we are witnessing a continued increase in losses to disease is because fish species are experiencing increased stressors that are compromising host welfare that in turn impacts disease susceptibility. This PhD project focussed on how fish welfare is impacted by different biotic and abiotic stressors, with an emphasis on host immunity and disease resistance. To accomplish this project, freshwater fish host-parasite models were utilised permitting long-term monitoring of infections in real time. Most stressors investigated negatively impacted fish disease resistance, with the first stressor investigated being mechanical disturbance associated with routine transportation practices. Beyond the increased susceptibility to disease seen in fish hosts exposed to stressors, this PhD also revealed that noise pollution significantly increases host mortality rates. However, in response to the ecological stressor, flow, no changes to fish immune gene expressions or pathogen burdens were seen. With regards to implementing simple measures for effective disease control, this project has revealed how the addition of structural enrichment to fish tanks significantly improved disease resistance while also reducing agnostic behaviour. The universal physiological cost of infection by significantly increasing host metabolic rates was also revealed. The final experimental study assessed how one of the most prevalent contaminants, microplastic, impacted host disease resistance, growth and mortality. Microplastic at variable concentrations significantly increased disease susceptibility and host mortality. Ultimately, this PhD project has furthered our understanding of how multiple emerging and widespread stressors are impacting fish host welfare through the lens of host-pathogen dynamics