Modeling Strategies to Improve the Dependability of Cloud Infrastructures

Cloud computing presents some challenges that need to be overcome, such as planning infrastructures that maintain availability when failure events and repair activities occur. Cloud infrastructure planning that addresses the dependability aspects is an essential activity because it ensures business continuity and client satisfaction. Redundancy mechanisms cold standby, warm standby and hot standby can be allocated to components of the cloud infrastructure to maintain the availability levels agreed in service level agreement (SLAs). Mathematical formalisms based on state space such as stochastic Petri nets and based on combinatorial as reliability block diagrams can be adopted to evaluate the dependability of cloud infrastructures considering the allocation of different redundancy mechanisms to its components. This chapter shows the adoption of the mathematical formalisms stochastic Petri nets and reliability block diagrams to dependability evaluation of cloud infrastructures with different redundancy mechanisms

Survey on Integration of Consensus Mechanisms in IoT-based Blockchains

While IoT systems are increasingly present in different areas of society, ensuring their data’s privacy, security, and inviolability becomes paramount. In this direction, Blockchain has been used to protect the security and immutability of data generated by IoT devices and sensors. At the heart of Blockchain solutions, consensus algorithms are crucial in ensuring the security of creating and writing data in new blocks. Choosing which consensus algorithms to utilise is critical because of a fundamental tradeoff between their security strength and response time. However, recent surveys of consensus mechanisms for IoT-based Blockchain focused on individually using and analysing these algorithms. Investigating the integration between these algorithms to address IoT-specific requirements better is a promising approach. In this context, this paper presents a literature review that explains and discusses consensus algorithms in IoT environments and their combinations. The review analyses eight dimensions that help understand existing proposals: ease of integration, scalability, latency, throughput, power consumption, configuration issues, integrated algorithms, and adversary tolerance. The final analysis also suggests and discusses open challenges in integrating multiple consensus algorithms considering the particularities of IoT systems

An Approach for Reducing the Gap between BPMN Models and Implementation Artifacts

The need for using high-level modeling tools (e.g. BPMN) isincreasing considerably. The proliferation of the service oriented architectures (SOA) is also apparent. In this context, there is a gap between the developed model and its execution. This work introduces the MoSC Translator which translates models produced in BPMN into executable WS-BPEL processes

Towards Generating Richer Code by Binding Security Abstractions to BPMN Task Types

This paper presents an approach for binding security requirements to different BPMN task types to create secure executable business processes.This paper presents an approach for binding security requirements to different BPMN task types to create secure executable business processes

Composição adaptativa de Web services

Web services têm desempenhado um importante papel no desenvolvimento de aplicações distribuídas. Em particular, a possibilidade de composição de serviços já implementados com o intuito de prover uma nova funcionalidade se constitui uma abordagem interessante para a construção de sistemas distribuídos e de processos de negócios (business processes), na medida em que diminui o tempo total de desenvolvimento e promove a reusabilidade de serviços já testados e utilizados. A possibilidade de realizar a composição de web services de forma dinâmica, em tempo de execução, aparece nesse contexto com uma elevada importância. A composição dinâmica permite que mudanças sejam percebidas pelo sistema durante a sua execução, sem a necessidade de reinicialização de sistemas, o que poderia levar a indisponibilidade do serviço e a possível perda de clientes. Algumas propostas têm surgido para composição dinâmica de web services, mas elas não adotam especificações já estáveis e notadamente difundidas, como WS-BPEL. Ao mesmo tempo, estas propostas usualmente implicam em modificações nas regras da especificação dos processos de negócios, dificultando ainda mais a implementação do sistema. Este trabalho propõe uma nova abordagem para possibilitar a adaptabilidade na composição de web services através de modificações na semântica da primitiva de invocação de serviços, mantendo a sintaxe do principal padrão existente para este fim (WS-BPEL) inalterada. A partir das modificações propostas, programadores podem definir composições dinâmicas de web services sem alterar o código fonte da aplicação. Como implementar a adaptação passa a ser tarefa do ambiente e não do programador, o que torna esta tarefa mais transparente para o mesmo. Por fim, a adaptabilidade surgiria como mais uma possibilidade no projeto, mantendo todas as outras características da composição inalterada

UP-Home: A Self-Adaptive Solution for Smart Home Security

Smart home devices are vulnerable to attacks that put their users’ security at risk. Vulnerabilities are discovered very frequently and can expose these devices through unsecured services. Meanwhile, the lack of standardisation in upgrade methods makes smart homes a potentially vulnerable environment. Furthermore, many manufacturers release their products and then abandon them, refusing to support security updates. As a result, security updates are needed to deal with the emergence of new attacks. There are several proposals to promote security in smart homes. However, there are rare solutions where changes for security purposes occur with little or no human intervention. This paper presents UP-Home, a self-adaptive solution that manages the security of smart homes. UP-Home aims to ensure that smart home devices meet the security requirements set by industry standards. The solution can continually identify and mitigate smart home security vulnerabilities. With autonomous computing techniques, UP-Home seeks to ensure the self-protection of devices and, consequently, the entire smart home. With the UP-Home evalu-ation, it was possible to notice significant improvements in the security of the smart home without any human intervention

UP-Home: A Self-Adaptive Solution for Smart Home Security

Smart home devices are vulnerable to attacks that put their users’ security at risk. Vulnerabilities are discovered very frequently and can expose these devices through unsecured services. Meanwhile, the lack of standardisation in upgrade methods makes smart homes a potentially vulnerable environment. Furthermore, many manufacturers release their products and then abandon them, refusing to support security updates. As a result, security updates are needed to deal with the emergence of new attacks. There are several proposals to promote security in smart homes. However, there are rare solutions where changes for security purposes occur with little or no human intervention. This paper presents UP-Home, a self-adaptive solution that manages the security of smart homes. UP-Home aims to ensure that smart home devices meet the security requirements set by industry standards. The solution can continually identify and mitigate smart home security vulnerabilities. With autonomous computing techniques, UP-Home seeks to ensure the self-protection of devices and, consequently, the entire smart home. With the UP-Home evalu-ation, it was possible to notice significant improvements in the security of the smart home without any human intervention