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- Approaches for Optimizing Virtual Machine Placement and Migration in Cloud EnvironmentsPublication . Filho, Manoel C. Silva; Monteiro, Cláudio C.; Inácio, Pedro R. M.; Freire, MárioCloud computing is a model for providing computing resources as a utility which faces several challenges on management of virtualized resources. Accordingly, virtual machine placement and migration are crucial to achieve multiple and conflicting goals. Regarding the complexity of these tasks and plethora of existing proposals, this work surveys the state-of-the-art in the area. It presents a cloud computing background, a review of several proposals, a discussion of problem formulations, advantages and shortcomings of reviewed works. Furthermore, it highlights the challenges for new solutions and provides several open issues, showing the relevancy of the topic in an increasing and demanding market.
- A User Trust System for Online Games: Part IPublication . Cardoso, Rui Costa; Freire, Mario; Gomes, AbelIn virtual worlds (including computer games), users develop trust relationships from their in-world interactions with others. However, these trust relationships end up not being represented in the data structures (or databases) of such virtual worlds, though they sometimes appear associated with reputation and recommendation systems. In addition, as far as we know, the user is not provided with a personal trust tool to sustain his/her decision-making while he/she interacts with other users in the virtual or game world. In order to come up with a computational formal representation of these personal trust relationships, we need to succeed in converting in-world interactions into reliable sources of trust-related data. In this paper, we develop the required formalisms to gather and represent in-world interactions-which are based on the activity theory-as well as a method to convert in-world interactions into trust networks. In the companion paper, we use these trust networks to produce a computational trust decision based on subjective logic. This solution aims at supporting in-world user (or avatar) decisions about others in the game world.
- Applications of artificial immune systems to computer security: A surveyPublication . Fernandes, Diogo A. B.; Freire, Mario; Fazendeiro, Paulo; Inácio, Pedro R. M.For the last two decades, artificial immune systems have been studied in various fields of knowledge. They were shown to be particularly effective tools at detecting anomalous behavior in the security domain of computer systems. This article introduces the principles of artificial immune systems and surveys several works applying such systems to computer security problems. The works herein discussed are summarized and open issues are pointed out afterwards, elaborating on a novel applicability of these systems to cloud computing environments.
- Blockchain-based Decentralized Application for Electronic Voting Using an Electronic IDPublication . Monteiro, José Diogo Soares Albergaria Serejo; Sequeiros, João B. F.; Freire, Mario; Inácio, Pedro R. M.In this work, we present a decentralized and self-tallying electronic voting protocol that substantially enhances the privacy of voters and diminishes centralization. ese properties are accomplished through a symbiotic relationship between the Ethereum Blockchain and the Portuguese electronic ID. Unlike previously proposed Blockchain e-voting protocols, this is the rst implementation that more closely ful lls most of the security requirements of a real-world voting scheme. Furthermore, our system improves currently in-use e-Voting systems by using a self-tallying protocol. us, each voting citizen is able to compute the election tally and has complete control over their own vote. e execution of this protocol is enforced using the consensus mechanism that safeguards the Ethereum Blockchain. To prove its feasibility, we tested the implementation on the o cial PoW (Proof of Work) test network of Ethereum (Ropsten). e - nancial and computational breakdowns are on par with the leading Blockchain e-voting protocol.
- Security Challenges of the Internet of ThingsPublication . Samaila, Musa Gwani; Neto, Miguel; Fernandes, Diogo A. B.; Freire, Mario; Inácio, Pedro R. M.The Internet of Things (IoT) is an environment in which ordinary and complex consumer products, buildings, bridges, animals or even people, etc. are embedded with sensors, equipped with a variety of communication technologies and given unique identifiers that can enable them connect to the Internet. This allows them to talk to each other, collect data and transfer data over the Internet. IoT has the potential to enhance the way we do things by increasing productivity and efficiency. It also has the prospects of delivering significant business benefits. Nonetheless, implementing secure communication in the IoT and integrating security mechanisms into some of its devices have been a major impediment to its progress, resulting in many privacy concerns. Although IoT is a hybrid network of the Internet, many security solutions for the Internet cannot be directly used on the resource-constrained devices of the IoT, hence the need for new security solutions. In this chapter, we discuss the security challenges of the IoT. First, we discuss some basic concepts of security and security requirements in the context of IoT. We then consider fundamental security issues in the IoT and thereafter highlight the security issues that need immediate attention.
- Security Threats and Possible Countermeasures in Applications Covering Different Industry DomainsPublication . Samaila, Musa Gwani; Sequeiros, João B. F.; Freire, Mario; Inácio, Pedro R. M.The world is witnessing the emerging role of Internet of Things (IoT) as a technology that is transforming different industries, global community and its economy. Currently, a plethora of interconnected smart devices have been deployed for diverse pervasive applications and services, and billions more are expected to be connected to the Internet in the near future. The potential benefits of IoT include improved quality of life, convenience, enhanced energy efficiency, and more productivity. Alongside these potential benefits, however, come increased security risks and potential for abuse. Arguably, this is partly because many IoT start-ups and electronics hobbyists lack security expertise, and some established companies do not make security a priority in their designs, and hence they produce IoT devices that are often ill-equipped in terms of security. In this paper, we discuss different IoT application areas, and identify security threats in IoT architecture. We consider security requirements and present typical security threats for each of the application domains. Finally, we present several possible security countermeasures, and introduce the IoT Hardware Platform Security Advisor (IoT-HarPSecA) framework, which is still under development. IoT-HarPSecA is aimed at facilitating the design and prototyping of secure IoT devices.
- CloudSim Plus: a Cloud Computing Simulation Framework Pursuing Software Engineering Principles for Improved Modularity, Extensibility and CorrectnessPublication . Filho, Manoel C. Silva; Oliveira, Raysa L.; Monteiro, Cláudio C.; Inácio, Pedro R. M.; Freire, MarioCloud computing is an established technology to provide computing resources on demand that currently faces several challenges. Main challenges include management of shared resources, energy consumption, load balancing, resource provisioning and allocation, and fulfilment of service level agreements (SLAs). Due to its inherent complexity, cloud simulation is largely used to experiment new models and algorithms. This work presents CloudSim Plus, an open source simulation framework that pursues conformance to software engineering principles and object-oriented design in order to provide an extensible, modular and accurate tool. Based on the CloudSim framework, it aims to improve several engineering aspects, such as maintainability, reusability and extensibility. This work shows the benefits of CloudSim Plus, its particular features, how it ensures more accuracy, extension facility and usage simplicity.
- Challenges of Securing Internet of Things DevicesPublication . Samaila, Musa Gwani; Neto, Miguel; Fernandes, Diogo A. B.; Freire, Mario; Inácio, Pedro R. M.The current vision of the Internet of Things (IoT) is to ensure that everything from everywhere is connected to the Internet at all times using Internet Protocol (IP). This idea has the potential of making homes, cities, electric grids, among others, safer, more efficient, and easier to manage. Nevertheless, a number of obstacles still remain to fully realize the IoT vision, with security and privacy among the most critical. Ensuring security and privacy in the IoT is particularly complicated, especially for the resource-constrained devices due to finite energy supply and low computing power. These factors are typically at odds with most of the existing security protocols and schemes proposed for the IoT because of the intensive computational nature of the cryptographic algorithms involved. This paper performs an extensive comparison of previous surveys on the subject, and shows its novelty with respect to the previous work. It describes 9 application domains and presents, in detail, security requirements, system models, threat models along with protocols and technologies for those 9 application areas. The survey also performs an exhaustive examination of some existing mechanisms and approaches proposed in the literature for ensuring security and privacy of IoT devices. Finally, it outlines some open research issues associated with IoT security.
- A Tutorial Introduction to IoT Design and Prototyping with ExamplesPublication . Meruje, Manuel; Samaila, Musa Gwani; Franqueira, Virginia; Freire, Mario; Inácio, Pedro R. M.The dramatic drop in the price of computing hardware, coupled with the recent breakthroughs in embedded systems design that enabled the integration of high-level software and low-level electronics, have created a paradigm shift in embedded systems development. This has led to the development of different varieties of user-friendly Internet of Things (IoT) hardware development platforms for IoT prototyping. The ubiquity of such prototyping platforms has undoubtedly contributed towards the explosive growth of the IoT, which is already seeping into all areas of human endeavor, including transportation, logistics, business, and healthcare. Building IoT projects that can be controlled over the Internet can be challenging, especially for beginners. This chapter discusses the design and development of prototypes for IoT applications with focus on Arduino and Raspberry Pi platforms. The aim is to provide insightful information on best practices for designing and prototyping IoT projects, as well as to serve as step-by-step guidelines for beginners.
- A User Trust System for Online Games: Part IIPublication . Cardoso, Rui Costa; Freire, Mario; Gomes, AbelRepresenting, manipulating, and inferring trust from the user point of view certainly is a grand challenge in virtual worlds, including online games. When someone meets an unknown individual, the question is “Can I trust him/her or not?” This requires the user to have access to a representation of trust about others, as well as a set of operators to undertake inference about the trustability of other users/players. In this paper, we employ a trust representation generated from in-world data in order to feed individual trust decisions. To achieve that purpose, we assume that such a representation of trust already exists; in fact, it was proposed in another paper of ours. Thus, the focus here is on the trust mechanisms required to infer trustability of other users/players. More specifically, we use an individual trust representation deployed as a trust network as base to the inference mechanism that employs two subjective logic operators (consensus and discount) to automatically derive trust decisions. The proposed trust inference system has been validated through OpenSimulator scenarios, which has led to a 5% increase on trustability of avatars in relation to the reference scenario (without trust).