From supply chains to demand networks. Agents in retailing: the electrical bazaar

A paradigm shift is taking place in logistics. The focus is changing from operational effectiveness to adaptation. Supply Chains will develop into networks that will adapt to consumer demand in almost real time. Time to market, capacity of adaptation and enrichment of customer experience seem to be the key elements of this new paradigm. In this environment emerging technologies like RFID (Radio Frequency ID), Intelligent Products and the Internet, are triggering a reconsideration of methods, procedures and goals. We present a Multiagent System framework specialized in retail that addresses these changes with the use of rational agents and takes advantages of the new market opportunities. Like in an old bazaar, agents able to learn, cooperate, take advantage of gossip and distinguish between collaborators and competitors, have the ability to adapt, learn and react to a changing environment better than any other structure. Keywords: Supply Chains, Distributed Artificial Intelligence, Multiagent System.Postprint (published version

Modeling network traffic on a global network-centric system with artificial neural networks

This dissertation proposes a new methodology for modeling and predicting network traffic. It features an adaptive architecture based on artificial neural networks and is especially suited for large-scale, global, network-centric systems. Accurate characterization and prediction of network traffic is essential for network resource sizing and real-time network traffic management. As networks continue to increase in size and complexity, the task has become increasingly difficult and current methodology is not sufficiently adaptable or scaleable. Current methods model network traffic with express mathematical equations which are not easily maintained or adjusted. The accuracy of these models is based on detailed characterization of the traffic stream which is measured at points along the network where the data is often subject to constant variation and rapid evolution. The main contribution of this dissertation is development of a methodology that allows utilization of artificial neural networks with increased capability for adaptation and scalability. Application on an operating global, broadband network, the Connexion by Boeingʼ network, was evaluated to establish feasibility. A simulation model was constructed and testing was conducted with operational scenarios to demonstrate applicability on the case study network and to evaluate improvements in accuracy over existing methods --Abstract, page iii

Analysis and selection of the simulation environment

This document provides the initial report of the Simulation work package (Work Package 4,WP4) of the CATNETS project. It contains an analisys of the requirements for a simulation tool to be used in CATNETS and an evaluation of a number of grid and general purpose simulators with respect to the selected requirements. A reasoned choice of a suitable simulator is performed based on the evaluation conducted. -- Diese Arbeit analysiert die Anforderungen an eine Simulationsumgebung für die Analyse der Katallaxie. Anhand von Kennzahlen wird die Auswahl der Simulationsumgebung bestimmt.Grid Computing

Survey on Various Aspects of Clustering in Wireless Sensor Networks Employing Classical, Optimization, and Machine Learning Techniques

A wide range of academic scholars, engineers, scientific and technology communities are interested in energy utilization of Wireless Sensor Networks (WSNs). Their extensive research is going on in areas like scalability, coverage, energy efficiency, data communication, connection, load balancing, security, reliability and network lifespan. Individual researchers are searching for affordable methods to enhance the solutions to existing problems that show unique techniques, protocols, concepts, and algorithms in the wanted domain. Review studies typically offer complete, simple access or a solution to these problems. Taking into account this motivating factor and the effect of clustering on the decline of energy, this article focuses on clustering techniques using various wireless sensor networks aspects. The important contribution of this paper is to give a succinct overview of clustering

Identity Management and Authorization Infrastructure in Secure Mobile Access to Electronic Health Records

We live in an age of the mobile paradigm of anytime/anywhere access, as the mobile device is the most ubiquitous device that people now hold. Due to their portability, availability, easy of use, communication, access and sharing of information within various domains and areas of our daily lives, the acceptance and adoption of these devices is still growing. However, due to their potential and raising numbers, mobile devices are a growing target for attackers and, like other technologies, mobile applications are still vulnerable. Health information systems are composed with tools and software to collect, manage, analyze and process medical information (such as electronic health records and personal health records). Therefore, such systems can empower the performance and maintenance of health services, promoting availability, readability, accessibility and data sharing of vital information about a patients overall medical history, between geographic fragmented health services. Quick access to information presents a great importance in the health sector, as it accelerates work processes, resulting in better time utilization. Additionally, it may increase the quality of care. However health information systems store and manage highly sensitive data, which raises serious concerns regarding patients privacy and safety, and may explain the still increasing number of malicious incidents reports within the health domain. Data related to health information systems are highly sensitive and subject to severe legal and regulatory restrictions, that aim to protect the individual rights and privacy of patients. Along side with these legislations, security requirements must be analyzed and measures implemented. Within the necessary security requirements to access health data, secure authentication, identity management and access control are essential to provide adequate means to protect data from unauthorized accesses. However, besides the use of simple authentication models, traditional access control models are commonly based on predefined access policies and roles, and are inflexible. This results in uniform access control decisions through people, different type of devices, environments and situational conditions, and across enterprises, location and time. Although already existent models allow to ensure the needs of the health care systems, they still lack components for dynamicity and privacy protection, which leads to not have desire levels of security and to the patient not to have a full and easy control of his privacy. Within this master thesis, after a deep research and review of the stat of art, was published a novel dynamic access control model, Socio-Technical Risk-Adaptable Access Control modEl (SoTRAACE), which can model the inherent differences and security requirements that are present in this thesis. To do this, SoTRAACE aggregates attributes from various domains to help performing a risk assessment at the moment of the request. The assessment of the risk factors identified in this work is based in a Delphi Study. A set of security experts from various domains were selected, to classify the impact in the risk assessment of each attribute that SoTRAACE aggregates. SoTRAACE was integrated in an architecture with requirements well-founded, and based in the best recommendations and standards (OWASP, NIST 800-53, NIST 800-57), as well based in deep review of the state-of-art. The architecture is further targeted with the essential security analysis and the threat model. As proof of concept, the proposed access control model was implemented within the user-centric architecture, with two mobile prototypes for several types of accesses by patients and healthcare professionals, as well the web servers that handles the access requests, authentication and identity management. The proof of concept shows that the model works as expected, with transparency, assuring privacy and data control to the user without impact for user experience and interaction. It is clear that the model can be extended to other industry domains, and new levels of risks or attributes can be added because it is modular. The architecture also works as expected, assuring secure authentication with multifactor, and secure data share/access based in SoTRAACE decisions. The communication channel that SoTRAACE uses was also protected with a digital certificate. At last, the architecture was tested within different Android versions, tested with static and dynamic analysis and with tests with security tools. Future work includes the integration of health data standards and evaluating the proposed system by collecting users’ opinion after releasing the system to real world.Hoje em dia vivemos em um paradigma móvel de acesso em qualquer lugar/hora, sendo que os dispositivos móveis são a tecnologia mais presente no dia a dia da sociedade. Devido à sua portabilidade, disponibilidade, fácil manuseamento, poder de comunicação, acesso e partilha de informação referentes a várias áreas e domínios das nossas vidas, a aceitação e integração destes dispositivos é cada vez maior. No entanto, devido ao seu potencial e aumento do número de utilizadores, os dispositivos móveis são cada vez mais alvos de ataques, e tal como outras tecnologias, aplicações móveis continuam a ser vulneráveis. Sistemas de informação de saúde são compostos por ferramentas e softwares que permitem recolher, administrar, analisar e processar informação médica (tais como documentos de saúde eletrónicos). Portanto, tais sistemas podem potencializar a performance e a manutenção dos serviços de saúde, promovendo assim a disponibilidade, acessibilidade e a partilha de dados vitais referentes ao registro médico geral dos pacientes, entre serviços e instituições que estão geograficamente fragmentadas. O rápido acesso a informações médicas apresenta uma grande importância para o setor da saúde, dado que acelera os processos de trabalho, resultando assim numa melhor eficiência na utilização do tempo e recursos. Consequentemente haverá uma melhor qualidade de tratamento. Porém os sistemas de informação de saúde armazenam e manuseiam dados bastantes sensíveis, o que levanta sérias preocupações referentes à privacidade e segurança do paciente. Assim se explica o aumento de incidentes maliciosos dentro do domínio da saúde. Os dados de saúde são altamente sensíveis e são sujeitos a severas leis e restrições regulamentares, que pretendem assegurar a proteção dos direitos e privacidade dos pacientes, salvaguardando os seus dados de saúde. Juntamente com estas legislações, requerimentos de segurança devem ser analisados e medidas implementadas. Dentro dos requerimentos necessários para aceder aos dados de saúde, uma autenticação segura, gestão de identidade e controlos de acesso são essenciais para fornecer meios adequados para a proteção de dados contra acessos não autorizados. No entanto, além do uso de modelos simples de autenticação, os modelos tradicionais de controlo de acesso são normalmente baseados em políticas de acesso e cargos pré-definidos, e são inflexíveis. Isto resulta em decisões de controlo de acesso uniformes para diferentes pessoas, tipos de dispositivo, ambientes e condições situacionais, empresas, localizações e diferentes alturas no tempo. Apesar dos modelos existentes permitirem assegurar algumas necessidades dos sistemas de saúde, ainda há escassez de componentes para accesso dinâmico e proteção de privacidade , o que resultam em níveis de segurança não satisfatórios e em o paciente não ter controlo directo e total sobre a sua privacidade e documentos de saúde. Dentro desta tese de mestrado, depois da investigação e revisão intensiva do estado da arte, foi publicado um modelo inovador de controlo de acesso, chamado SoTRAACE, que molda as diferenças de acesso inerentes e requerimentos de segurança presentes nesta tese. Para isto, o SoTRAACE agrega atributos de vários ambientes e domínios que ajudam a executar uma avaliação de riscos, no momento em que os dados são requisitados. A avaliação dos fatores de risco identificados neste trabalho são baseados num estudo de Delphi. Um conjunto de peritos de segurança de vários domínios industriais foram selecionados, para classificar o impacto de cada atributo que o SoTRAACE agrega. O SoTRAACE foi integrado numa arquitectura para acesso a dados médicos, com requerimentos bem fundados, baseados nas melhores normas e recomendações (OWASP, NIST 800-53, NIST 800-57), e em revisões intensivas do estado da arte. Esta arquitectura é posteriormente alvo de uma análise de segurança e modelos de ataque. Como prova deste conceito, o modelo de controlo de acesso proposto é implementado juntamente com uma arquitetura focada no utilizador, com dois protótipos para aplicações móveis, que providênciam vários tipos de acesso de pacientes e profissionais de saúde. A arquitetura é constituída também por servidores web que tratam da gestão de dados, controlo de acesso e autenticação e gestão de identidade. O resultado final mostra que o modelo funciona como esperado, com transparência, assegurando a privacidade e o controlo de dados para o utilizador, sem ter impacto na sua interação e experiência. Consequentemente este modelo pode-se extender para outros setores industriais, e novos níveis de risco ou atributos podem ser adicionados a este mesmo, por ser modular. A arquitetura também funciona como esperado, assegurando uma autenticação segura com multi-fator, acesso e partilha de dados segura baseado em decisões do SoTRAACE. O canal de comunicação que o SoTRAACE usa foi também protegido com um certificado digital. A arquitectura foi testada em diferentes versões de Android, e foi alvo de análise estática, dinâmica e testes com ferramentas de segurança. Para trabalho futuro está planeado a integração de normas de dados de saúde e a avaliação do sistema proposto, através da recolha de opiniões de utilizadores no mundo real