Solutions and Tools for Secure Communication in Wireless Sensor Networks

Secure communication is considered a vital requirement in Wireless Sensor Network (WSN) applications. Such a requirement embraces different aspects, including confidentiality, integrity and authenticity of exchanged information, proper management of security material, and effective prevention and reaction against security threats and attacks. However, WSNs are mainly composed of resource-constrained devices. That is, network nodes feature reduced capabilities, especially in terms of memory storage, computing power, transmission rate, and energy availability. As a consequence, assuring secure communication in WSNs results to be more difficult than in other kinds of network. In fact, trading effectiveness of adopted solutions with their efficiency becomes far more important. In addition, specific device classes or technologies may require to design ad hoc security solutions. Also, it is necessary to efficiently manage security material, and dynamically cope with changes of security requirements. Finally, security threats and countermeasures have to be carefully considered since from the network design phase. This Ph.D. dissertion considers secure communication in WSNs, and provides the following contributions. First, we provide a performance evaluation of IEEE 802.15.4 security services. Then, we focus on the ZigBee technology and its security services, and propose possible solutions to some deficiencies and inefficiencies. Second, we present HISS, a highly scalable and efficient key management scheme, able to contrast collusion attacks while displaying a graceful degradation of performance. Third, we present STaR, a software component for WSNs that secures multiple traffic flows at the same time. It is transparent to the application, and provides runtime reconfigurability, thus coping with dynamic changes of security requirements. Finally, we describe ASF, our attack simulation framework for WSNs. Such a tool helps network designers to quantitatively evaluate effects of security attacks, produce an attack ranking based on their severity, and thus select the most appropriate countermeasures

Service Quality and Profit Control in Utility Computing Service Life Cycles

Utility Computing is one of the most discussed business models in the context of Cloud Computing. Service providers are more and more pushed into the role of utilities by their customer's expectations. Subsequently, the demand for predictable service availability and pay-per-use pricing models increases. Furthermore, for providers, a new opportunity to optimise resource usage offers arises, resulting from new virtualisation techniques. In this context, the control of service quality and profit depends on a deep understanding of the representation of the relationship between business and technique. This research analyses the relationship between the business model of Utility Computing and Service-oriented Computing architectures hosted in Cloud environments. The relations are clarified in detail for the entire service life cycle and throughout all architectural layers. Based on the elaborated relations, an approach to a delivery framework is evolved, in order to enable the optimisation of the relation attributes, while the service implementation passes through business planning, development, and operations. Related work from academic literature does not cover the collected requirements on service offers in this context. This finding is revealed by a critical review of approaches in the fields of Cloud Computing, Grid Computing, and Application Clusters. The related work is analysed regarding appropriate provision architectures and quality assurance approaches. The main concepts of the delivery framework are evaluated based on a simulation model. To demonstrate the ability of the framework to model complex pay-per-use service cascades in Cloud environments, several experiments have been conducted. First outcomes proof that the contributions of this research undoubtedly enable the optimisation of service quality and profit in Cloud-based Service-oriented Computing architectures

A simulation approach for increased safety in advanced C-ITS scenarios

Com os recentes desenvolvimentos em diferentes áreas de conhecimento, como redes de comunicação sem fio e sensores, bem como a evolução recente em vários tópicos na área da Computação, os Sistemas Inteligentes e Cooperativos de Transporte (CITSs) tornaram-se um tema muito importante, e espera-se que comecem a ser cada vez mais implementados num futuro próximo. Nesta tese, é feita uma análise sobre estes sistemas e diferentes possiveis cenários focando no cenário de Platooning, assim como sobre comunicações Veículo-a-Tudo (V2X) com foco no ETSI ITS-G5, o standard europeu mais amplamente aceite na indústria automóvel para este tipo de comunicações. O desenvolvimento de duas ferramentas de co-simulação para análise de cenários C-ITS usando comunicações veículo para veículo (V2V), foi feito no contexto desta tese. COPADRIVe é uma ferramenta de co-simulação que junta um simulador de rede e um simulador robótico. A outra ferramenta de co-simulação, é uma ferramenta hardware-in-the-loop que úne um simulador robótico com comunicações feitas através de hardware real, On-Board units (OBUs). Ambas as ferramentas foram desenvolvidas e usadas como forma de análise e teste de situações de Platooning e componentes de software para implementação neste tipo de cenários. Este desenvolvimento teve origem na necessidade de existência deste tipo de ferramentas para suporte dos desenvolvimentos feitos no contexto dos Projetos europeus de I&D SafeCOP e ENABLE-S3, onde o CISTER participava ativamente.With the developments in different areas like Wireless Communication Networks and sensors, as well as, the recent evolution on various topics on Computing, Cooperative Intelligent Transportation Systems(C-ITSs) became a hot topic for research, and are expected to be increasingly deployed in the future. From the different possible scenarios, in this thesis, we focus in analyzing Cooperative Platooning and particularly, in enabling a set of simulation tools capable of encompassing the supporting Vehicle-to-Everything(V2X) communications guaranteed by the ETSI ITS-G5, the most widely accepted European standard on the automotive industry for these kind of communications. Therefore this thesis presents the development of two co-simulation tools for analysis of C-ITS scenarios using Vehicle-to-Vehicle(V2V) communications. First, COPADRIVe is a co-simulation tool joining together a network simulator and a robotic simulator. The other co-simulation tool, uses a a hardware-in-theloop approach one bridging a robotic simulator with real communications via OnBoard-Units (OBUs). Both tools were developed and used as the means to test and analyze Platooning scenarios and software components relevant in such applications, importantly. These tools’ were developed in line with the R&D European Projects SafeCOP and ENABLE-S3, where CISTER was and active participant