Risk Balance in Exchange Protocols

We study the behaviour of rational agents in exchange protocols which rely on trustees. We allow malicious parties to compromise the trustee by paying a cost and, thereby, present a game analysis that advocates exchange protocols which induce balanced risks on the participants. We also present a risk-balanced protocol for fair confidential secret comparison

Low-latency mix networks for anonymous communication

Every modern online application relies on the network layer to transfer information, which exposes the metadata associated with digital communication. These distinctive characteristics encapsulate equally meaningful information as the content of the communication itself and allow eavesdroppers to uniquely identify users and their activities. Hence, by exposing the IP addresses and by analyzing patterns of the network traffic, a malicious entity can deanonymize most online communications. While content confidentiality has made significant progress over the years, existing solutions for anonymous communication which protect the network metadata still have severe limitations, including centralization, limited security, poor scalability, and high-latency. As the importance of online privacy increases, the need to build low-latency communication systems with strong security guarantees becomes necessary. Therefore, in this thesis, we address the problem of building multi-purpose anonymous networks that protect communication privacy. To this end, we design a novel mix network Loopix, which guarantees communication unlinkability and supports applications with various latency and bandwidth constraints. Loopix offers better security properties than any existing solution for anonymous communications while at the same time being scalable and low-latency. Furthermore, we also explore the problem of active attacks and malicious infrastructure nodes, and propose a Miranda mechanism which allows to efficiently mitigate them. In the second part of this thesis, we show that mix networks may be used as a building block in the design of a private notification system, which enables fast and low-cost online notifications. Moreover, its privacy properties benefit from an increasing number of users, meaning that the system can scale to millions of clients at a lower cost than any alternative solution

Methodologies synthesis

This deliverable deals with the modelling and analysis of interdependencies between critical infrastructures, focussing attention on two interdependent infrastructures studied in the context of CRUTIAL: the electric power infrastructure and the information infrastructures supporting management, control and maintenance functionality. The main objectives are: 1) investigate the main challenges to be addressed for the analysis and modelling of interdependencies, 2) review the modelling methodologies and tools that can be used to address these challenges and support the evaluation of the impact of interdependencies on the dependability and resilience of the service delivered to the users, and 3) present the preliminary directions investigated so far by the CRUTIAL consortium for describing and modelling interdependencies

Two Cents for Strong Anonymity: The Anonymous Post-office Protocol

We introduce the {\em Anonymous Post-office Protocol (AnonPoP)}, a practical strongly-anonymous messaging system. AnonPoP offers anonymity against globally eavesdropping adversaries that control a majority of AnonPoP\u27s servers. AnonPoP design combines effectively known techniques such as (synchronous) mix-cascade and constant sending rate, with several new techniques including {\em request-pool}, {\em bad-server isolation} and {\em per-epoch mailboxes}. \newline AnonPoP is {\em affordable}, with monthly costs of $2$\textcent\ per client, and {\em efficient} with respect to latency, communication, and energy, making it suitable for mobile clients. We developed an API that allows other applications to use AnonPoP for adding strong anonymity. We validated the system and its usability by experiments in cloud-based deployment and simulations, including a POC Android messaging application and a `double-blinded\u27 usability study

Protecting an Industrial AC Drive Application against Cyber Sabotage

Vuonna 2010 havaittua, erittäin kehittynyttä tietokonevirusta nimeltä Stuxnet on kuvailtu myös ensimmäiseksi kybersodan aseeksi, koska eri lähteiden mukaan se tuhosi vähintään 1 000 uraania rikastavaa kaasusentrifugia Iranissa. Tämä kybersabotaasi suoritettiin tunkeutumalla teolliseen ohjausjärjestelmään, kytkemällä sentrifugeja ohjaavien taajuusmuuttajien suojatoiminnot pois päältä ja pyörittämällä niitä niin suurilla nopeuksilla, että keskipakoisvoimat aiheuttivat roottoreiden repeämisen. Dekantterit ovat toisenlaisia sentrifugeja, joita käytetään erottamaan kiinteät aineet nestemäisistä useilla eri teollisuudenaloilla, kuten esimerkiksi vedenkäsittelyssä ja kaivostoiminnassa. Dekantterisentrifugit, eli tarkemmin kiinteärumpuiset, ruuvipurkuiset lingot, käyvät usein epätahtikoneilla ja taajuusmuuttajilla. Olettaen, että Stuxnet-tapauksen kaltainen tuho voidaan estää sopivilla turvajärjestelmillä, toimenpiteitä dekantterilingon suojelemiseksi tutkittiin käyttäen kirjallisuutta ja nykyistä tietoturva- ja henkilöturvaominaisuustarjontaa seuraavilta uudenaikaisilta taajuusmuuttajilta, joissa on Ethernet-pohjainen kenttäväyläyhteys: ABB ACS880-01, Rockwell Allen-Bradley PowerFlex 755 ja Siemens SINAMICS S110. Rajoitetun arvioinnin tuloksena taajuusmuuttajien pahin kyberturvallisuuteen liittyvä haavoittuvuus on tyypillinen monille kenttäväyliä käyttäville automaatiolaitteille: täysivaltainen asetusten muutos on mahdollista oletusarvoisesti ilman minkäänlaista käyttäjähallintaa. Kuitenkin toiminnallisen turvallisuuden asetukset voidaan suojata salasanalla, joten standardoitu turvafunktio nimeltä turvallisesti rajoitettu nopeus on toteuttamiskelpoinen ratkaisu dekantterilingon suojelemiseksi kybersabotaasilta. Liitteenä olevaa tarkistuslistaa seuraamalla dekanttereissa käytettävät taajuusmuuttajat voidaan konfiguroida mahdollisimman hyvin kyberturvallisuuden kannalta.Discovered in 2010, the highly advanced computer virus called Stuxnet, also described as the first weapon of cyber warfare, reportedly destroyed at least 1,000 gas centrifuges enriching uranium in Iran. This kind of act of cyber sabotage was conducted by compromising the industrial control system, disabling protection functions of AC drives running the centrifuges, and making them spin at such high speeds that centrifugal forces caused their rotors to rupture. Decanters are another type of centrifuges used to separate solids from liquids in many industries including water treatment and mining for example. Also known as solid-bowl, scroll-discharge centrifuges, decanters are commonly powered by induction motors and AC drives. Assuming havoc similar to the Stuxnet case can be prevented with suitable safety systems, a review was conducted on the protection methods for decanter centrifuges based on literature and the current security and safety features of the following modern AC drives with Ethernet-based fieldbus connectivity: ABB ACS880-01, Rockwell Allen-Bradley PowerFlex 755, and Siemens SINAMICS S110. As a result of the limited assessment, the worst vulnerability related to cybersecurity of the AC drives is typical to many automation devices using fieldbuses: total configuration is possible remotely without any authentication by default. However, the functional safety configuration can be protected by means of a password, therefore allowing a standardized safety function called safely-limited speed (SLS) to become a viable solution for protecting the decanter centrifuge against cyber sabotage. By following the supplied checklist, it is possible to configure AC drives used with decanters optimally in terms of cybersecurity

Improving cyber security in industrial control system environment.

Integrating industrial control system (ICS) with information technology (IT) and internet technologies has made industrial control system environments (ICSEs) more vulnerable to cyber-attacks. Increased connectivity has brought about increased security threats, vulnerabilities, and risks in both technology and people (human) constituents of the ICSE. Regardless of existing security solutions which are chiefly tailored towards technical dimensions, cyber-attacks on ICSEs continue to increase with a proportionate level of consequences and impacts. These consequences include system failures or breakdowns, likewise affecting the operations of dependent systems. Impacts often include; marring physical safety, triggering loss of lives, causing huge economic damages, and thwarting the vital missions of productions and businesses. This thesis addresses uncharted solution paths to the above challenges by investigating both technical and human-factor security evaluations to improve cyber security in the ICSE. An ICS testbed, scenario-based, and expert opinion approaches are used to demonstrate and validate cyber-attack feasibility scenarios. To improve security of ICSs, the research provides: (i) an adaptive operational security metrics generation (OSMG) framework for generating suitable security metrics for security evaluations in ICSEs, and a list of good security metrics methodology characteristics (scope-definitive, objective-oriented, reliable, simple, adaptable, and repeatable), (ii) a technical multi-attribute vulnerability (and impact) assessment (MAVCA) methodology that considers and combines dynamic metrics (temporal and environmental) attributes of vulnerabilities with the functional dependency relationship attributes of the vulnerability host components, to achieve a better representation of exploitation impacts on ICSE networks, (iii) a quantitative human-factor security (capability and vulnerability) evaluation model based on human-agent security knowledge and skills, used to identify the most vulnerable human elements, identify the least security aspects of the general workforce, and prioritise security enhancement efforts, and (iv) security risk reduction through critical impact point assessment (S2R-CIPA) process model that demonstrates the combination of technical and human-factor security evaluations to mitigate risks and achieve ICSE-wide security enhancements. The approaches or models of cyber-attack feasibility testing, adaptive security metrication, multi-attribute impact analysis, and workforce security capability evaluations can support security auditors, analysts, managers, and system owners of ICSs to create security strategies and improve cyber incidence response, and thus effectively reduce security risk.PhD in Manufacturin

Investigations in the design and analysis of key-stream generators

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Understanding evolutionary processes during past Quaternary climatic cycles: Can it be applied to the future?

Climate change affected ecological community make-up during the Quaternary which was probably both the cause of, and was caused by, evolutionary processes such as species evolution, adaptation and extinction of species and populations

ENERGY JUSTICE AND U.S. ENERGY POLICY: CASE STUDY APPLICATIONS EXPLORING U.S. ENERGY POLICY THROUGH AN ENERGY JUSTICE FRAMEWORK

This thesis presents three examples of U.S. energy policy and demonstrates how these policies violate the principles of energy justice. First, requiring only Federal agencies to obtain a percentage of energy production from renewables violates the distributive energy justice principle through a lack of a federal renewable energy policy which distributes the potential for unequal electrical grid failure to populations. Second, U.S. energy policy violates the procedural energy justice principle through inequitable participation and poor knowledge dissemination that, in some cases, contributes to stagnant renewable targets during the decision-making process and inequitable distribution of the benefits associated with renewable energy arguably resulting from differential representation of economic groups in policy decision making. Third, the United States’ continued reliance on and subsidization of fossil fuel extraction and use, violates the prohibitive energy justice principle by causing physical harm to humans and the environment. Finally, a lack of federal renewable energy policy hinders comprehensive energy policy including diversifying the U.S. renewable energy portfolios. Considering energy policy through the framework of energy justice offers a means of evaluating existing policy and can improve future energy policy decision-making. Demanding energy justice ensures that all populations have equitable distribution, participation, and access to affordable, efficient, and clean energy technologies that contribute to obtaining basic needs