Developing a distributed electronic health-record store for India

The DIGHT project is addressing the problem of building a scalable and highly available information store for the Electronic Health Records (EHRs) of the over one billion citizens of India

Polynomial Size Analysis of First-Order Shapely Functions

We present a size-aware type system for first-order shapely function definitions. Here, a function definition is called shapely when the size of the result is determined exactly by a polynomial in the sizes of the arguments. Examples of shapely function definitions may be implementations of matrix multiplication and the Cartesian product of two lists. The type system is proved to be sound w.r.t. the operational semantics of the language. The type checking problem is shown to be undecidable in general. We define a natural syntactic restriction such that the type checking becomes decidable, even though size polynomials are not necessarily linear or monotonic. Furthermore, we have shown that the type-inference problem is at least semi-decidable (under this restriction). We have implemented a procedure that combines run-time testing and type-checking to automatically obtain size dependencies. It terminates on total typable function definitions.Comment: 35 pages, 1 figur

Smart workplaces: a system proposal for stress management

Over the past last decades of contemporary society, workplaces have become the primary source of many health issues, leading to mental problems such as stress, depression, and anxiety. Among the others, environmental aspects have shown to be the causes of stress, illness, and lack of productivity. With the arrival of new technologies, especially in the smart workplaces field, most studies have focused on investigating the building energy efficiency models and human thermal comfort. However, little has been applied to occupants’ stress recognition and well-being overall. Due to this fact, this present study aims to propose a stress management solution for an interactive design system that allows the adapting of comfortable environmental conditions according to the user preferences by measuring in real-time the environmental and biological characteristics, thereby helping to prevent stress, as well as to enable users to cope stress when being stressed. The secondary objective will focus on evaluating one part of the system: the mobile application. The proposed system uses several usability methods to identify users’ needs, behavior, and expectations from the user-centered design approach. Applied methods, such as User Research, Card Sorting, and Expert Review, allowed us to evaluate the design system according to Heuristics Analysis, resulting in improved usability of interfaces and experience. The study presents the research results, the design interface, and usability tests. According to the User Research results, temperature and noise are the most common environmental stressors among the users causing stress and uncomfortable conditions to work in, and the preference for physical activities over the digital solutions for coping with stress. Additionally, the System Usability Scale (SUS) results identified that the system’s usability was measured as “excellent” and “acceptable” with a final score of 88 points out of the 100. It is expected that these conclusions can contribute to future investigations in the smart workplaces study field and their interaction with the people placed there.Nas últimas décadas da sociedade contemporânea, o local de trabalho tem se tornado principal fonte de muitos problemas de saúde mental, como o stress, depressão e ansiedade. Os aspetos ambientais têm se revelado como as causas de stress, doenças, falta de produtividade, entre outros. Atualmente, com a chegada de novas tecnologias, principalmente na área de locais de trabalho inteligentes, a maioria dos estudos tem se concentrado na investigação de modelos de eficiência energética de edifícios e conforto térmico humano. No entanto, pouco foi aplicado ao reconhecimento do stress dos ocupantes e ao bem-estar geral das pessoas. Diante disso, o objetivo principal é propor um sistema de design de gestão do stress para um sistema de design interativo que permita adaptar as condições ambientais de acordo com as preferências de utilizador, medindo em tempo real as características ambientais e biológicas, auxiliando assim na prevenção de stress, bem como ajuda os utilizadores a lidar com o stress quando estão sob o mesmo. O segundo objetivo é desenhar e avaliar uma parte do projeto — o protótipo da aplicação móvel através da realização de testes de usabilidade. O sistema proposto resulta da abordagem de design centrado no utilizador, utilizando diversos métodos de usabilidade para identificar as necessidades, comportamentos e as expectativas dos utilizadores. Métodos aplicados, como Pesquisa de Usuário, Card Sorting e Revisão de Especialistas, permitiram avaliar o sistema de design de acordo com a análise heurística, resultando numa melhoria na usabilidade das interfaces e experiência. O estudo apresenta os resultados da pesquisa, a interface do design e os testes de usabilidade. De acordo com os resultados de User Research, a temperatura e o ruído são os stressores ambientais mais comuns entre os utilizadores, causando stresse e condições menos favoráveis para trabalhar, igualmente existe uma preferência por atividades físicas sobre as soluções digitais na gestão do stresse. Adicionalmente, os resultados de System Usability Scale (SUS) identificaram a usabilidade do sistema de design como “excelente” e “aceitável” com pontuação final de 88 pontos em 100. É esperado que essas conclusões possam contribuir para futuras investigações no campo de estudo dos smart workplaces e sua interação com os utilizadores

Scaling Distributed Ledgers and Privacy-Preserving Applications

This thesis proposes techniques aiming to make blockchain technologies and smart contract platforms practical by improving their scalability, latency, and privacy. This thesis starts by presenting the design and implementation of Chainspace, a distributed ledger that supports user defined smart contracts and execute user-supplied transactions on their objects. The correct execution of smart contract transactions is publicly verifiable. Chainspace is scalable by sharding state; it is secure against subsets of nodes trying to compromise its integrity or availability properties through Byzantine Fault Tolerance (BFT). This thesis also introduces a family of replay attacks against sharded distributed ledgers targeting cross-shard consensus protocols; they allow an attacker, with network access only, to double-spend resources with minimal efforts. We then build Byzcuit, a new cross-shard consensus protocol that is immune to those attacks and that is tailored to run at the heart of Chainspace. Next, we propose FastPay, a high-integrity settlement system for pre-funded payments that can be used as a financial side-infrastructure for Chainspace to support low-latency retail payments. This settlement system is based on Byzantine Consistent Broadcast as its core primitive, foregoing the expenses of full atomic commit channels (consensus). The resulting system has extremely low-latency for both confirmation and payment finality. Finally, this thesis proposes Coconut, a selective disclosure credential scheme supporting distributed threshold issuance, public and private attributes, re-randomization, and multiple unlinkable selective attribute revelations. It ensures authenticity and availability even when a subset of credential issuing authorities are malicious or offline, and natively integrates with Chainspace to enable a number of scalable privacy-preserving applications

Security of Contactless Smart Card Protocols

Tato práce analyzuje hrozby pro protokoly využívající bezkontaktní čipové karty a představuje metodu pro poloautomatické hledání zranitelností v takových protokolech pomocí model checkingu. Návrh a implementace bezpečných aplikací jsou obtížné úkoly, i když je použit bezpečný hardware. Specifikace na vysoké úrovni abstrakce může vést k různým implementacím. Je důležité používat čipovou kartu správně, nevhodná implementace protokolu může přinést zranitelnosti, i když je protokol sám o sobě bezpečný. Cílem této práce je poskytnout metodu, která může být využita vývojáři protokolů k vytvoření modelu libovolné čipové karty, se zaměřením na bezkontaktní čipové karty, k vytvoření modelu protokolu a k použití model checkingu pro nalezení útoků v tomto modelu. Útok může být následně proveden a pokud není úspěšný, model je upraven pro další běh model checkingu. Pro formální verifikaci byla použita platforma AVANTSSAR, modely jsou psány v jazyce ASLan++. Jsou poskytnuty příklady pro demonstraci použitelnosti navrhované metody. Tato metoda byla použita k nalezení slabiny bezkontaktní čipové karty Mifare DESFire. Tato práce se dále zabývá hrozbami, které není možné pokrýt navrhovanou metodou, jako jsou útoky relay. This thesis analyses contactless smart card protocol threats and presents a method of semi-automated vulnerability finding in such protocols using model checking. Designing and implementing secure applications is difficult even when secure hardware is used. High level application specifications may lead to different implementations. It is important to use the smart card correctly, inappropriate protocol implementation may introduce a vulnerability, even if the protocol is secure by itself. The goal of this thesis is to provide a method that can be used by protocol developers to create a model of arbitrary smart card, with focus on contactless smart cards, to create a model of the protocol, and to use model checking to find attacks in this model. The attack can be then executed and if not successful, the model is refined for another model checker run. The AVANTSSAR platform was used for the formal verification, models are written in the ASLan++ language. Examples are provided to demonstrate usability of the proposed method. This method was used to find a weakness of Mifare DESFire contactless smart card. This thesis also deals with threats not possible to cover by the proposed method, such as relay attacks.

FLACOS’08 Workshop proceedings

The 2nd Workshop on Formal Languages and Analysis of Contract-Oriented Software (FLACOS’08) is held in Malta. The aim of the workshop is to bring together researchers and practitioners working on language-based solutions to contract-oriented software development. The workshop is partially funded by the Nordunet3 project “COSoDIS” (Contract-Oriented Software Development for Internet Services) and it attracted 25 participants. The program consists of 4 regular papers and 10 invited participant presentations

Junos Pulse Secure Access Service Administration Guide

This guide describes basic configuration procedures for Juniper Networks Secure Access Secure Access Service. This document was formerly titled Secure Access Administration Guide. This document is now part of the Junos Pulse documentation set. This guide is designed for network administrators who are configuring and maintaining a Juniper Networks Secure Access Service device. To use this guide, you need a broad understanding of networks in general and the Internet in particular, networking principles, and network configuration. Any detailed discussion of these concepts is beyond the scope of this guide.The Juniper Networks Secure Access Service enable you to give employees, partners, and customers secure and controlled access to your corporate data and applications including file servers, Web servers, native messaging and e-mail clients, hosted servers, and more from outside your trusted network using just a Web browser. Secure Access Service provide robust security by intermediating the data that flows between external users and your company’s internal resources. Users gain authenticated access to authorized resources through an extranet session hosted by the appliance. During intermediation, Secure Access Service receives secure requests from the external, authenticated users and then makes requests to the internal resources on behalf of those users. By intermediating content in this way, Secure Access Service eliminates the need to deploy extranet toolkits in a traditional DMZ or provision a remote access VPN for employees. To access the intuitive Secure Access Service home page, your employees, partners, and customers need only a Web browser that supports SSL and an Internet connection. This page provides the window from which your users can securely browse Web or file servers, use HTML-enabled enterprise applications, start the client/server application proxy, begin a Windows, Citrix, or Telnet/SSH terminal session, access corporate e-mail servers, start a secured layer 3 tunnel, or schedule or attend a secure online meeting

An introduction to Quality of Security Services

We examine the concept of security as a dimension of Quality of Service in distributed systems. We provide a discussion and examples of user- specified security variables and show how the range of service levels associated with these variables can support the provision of Quality of Security Service. We also discuss various design implications regarding security ranges provided in a QoS-aware distributed system. Our goal has been to provide an understanding of QoSS and variant security, and to determine whether these concepts can be useful in improving security service and system performance in QoS-aware distributed systems. We described the general requirements for system attributes to participate in the provision of Quality of Service, and described how certain security attributes might meet these requirements. We then described various forms of user and application security "ranges "and showed how these ranges can make sense in relation to existing security policies, when those ranges are presented as user choices. Finally we described security ranges as forming a coherent system of relationships in a distributed multi-tiered system. Our conclusion is that it may be possible for security to be a semantically meaningful dimension of Quality of Service without compromising existing security policies. Further study is needed to understand the effectiveness of QoSS in improving system performance in QoS-aware systems.Approved for public release; distribution is unlimited