ESTGV - DI - Artigo em revista científica, não indexada ao WoS/Scopus
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- Openstack: a virtualization overviewPublication . Martins, Pedro Oliveira; Mechraoui, Faouzi; Caldeira, FilipeThe major cloud computing software companies offer a new concept, on which resources are virtualized to provide these as a service on the internet. Currently, there are multiple service providers, and additional options to virtualize services on-premises. OpenStack is an open-source alternative to create virtual local or cloud setups, which supports petabytes of data, unlimited scale, and configurable networking. These features make this tool suitable for large scale virtualization, reducing maintenance costs and optimizing hardware resource utilization (e.g., schools, government). This paper presents an overview of the study of the OpenStack software, oriented to build a scalable hosting architecture suitable for an educational setup. Functional and architectural details are discussed to implement unique cloud computing to fit virtualization purposes. An experimental virtualization setup is described in the scope of an educational scenario. Finally, a guideline to configure OpenStack is given.
- On the Use of Ontology Data for Protecting Critical InfrastructuresPublication . Henriques, João; Caldeira, Filipe; Cruz, Tiago; Simões, PauloModern societies increasingly depend on products and services provided by Critical Infrastructures (CI). The Security Information and Event Management (SIEM) systems in charge of protecting these CIs usually collect and process data from specialised sources. However, they usually integrate only a small fraction of the whole data sources existing in the CI. Valuable generic data sources are missing in this process, such as human resources databases, staff check clocks, and outsourced service providers. To address this gap, the authors propose a framework that takes a Semantic Web approach for automated collection and processing of corporate data from multiple heterogeneous sources.
- Policy-based networking: Applications to firewall managementPublication . Caldeira, Filipe; Monteiro, E.This paper describes a policy-based approach to firewall management. The Policy-Based Networking (PBN) architecture proposed by the Policy Framework Group of lnternet Engineering Task Force (1ETF) is analysed, together with the communication protocols, policy specification languages, and the necessary information models. An overview of policy specification languages applicability to PBN architecture is presented paying particular attention to the specification of security policies through Security Policy Specification Language (SPSL). The Common Open Policy Service protocol (coPs) and its variant, coPs for Policy provisioning (COPS-PR), both used for the transport of policy information, are also presented. The paper continues with a description of an application of the PBN architecture to firewall management. The proposed architecture is presented and its implementation issues are analysed with some usage examples. The paper concludes with the evaluation of the policybased approach to firewall management.
- Trust Based Interdependency Weighting for On-Line Risk Monitoring in Interdependent Critical InfrastructuresPublication . Caldeira, Filipe; Schaberreiter, Thomas; Varrette, Sébastien; Monteiro, Edmundo; Simões, Paulo; Bouvry, Pascal; Khadraoui, DjamelCritical infrastructure (CI) services are constantly consumed by the society and are not expected to fail. A common definition states that CIs are so vital to our society that a disruption would have a severe impact on both the society and the economy. CI sectors include, amongst others, electricity, telecommunication and transport. CIs can be mutually dependent on each others services and a failure in one of these elements can cascade to another (inter)dependent CI. CI security modelling was introduced in previous work to enable on-line risk monitoring in CIs that depend on each other by exchanging risk alerts expressed in terms of a breach of Confidentiality, a breach of Integrity and degrading Availability (C,I,A). While generally providing a solid basis for risk monitoring, there is no way of evaluating if a risk alert received from an external CI is accurate. In this paper we propose a solution to this problem by adding a trust based component to the CI security model in order to improve its accuracy and resilience to inconsistent or inaccurate risk alerts provided by (inter)dependent CIs, allowing to evaluate the correctness of the received alerts. The proposed approach is validated on a realistic scenario by evaluating a dependency between the computing and the telecommunication sectors in the context of the Grid'5000 platform.
- Design of Data Management Service Platform for Intelligent Electric Vehicle Charging Controller Multi-charger ModelPublication . Baptista, Pedro; Rosado, José; Caldeira, Filipe; Cardoso, FilipeThe electric charging solutions for the residential market imply, in many situations, an increase in the contracted power in order to allow to perform an efficient charging cycle that starts when the charger is connected and ends when the VE battery is fully charged. However, the increase in contracted power is not always the best solution for faster and more efficient charging. With a focus on the residential market, the presented architecture is suitable for single-use and shared connection points, which are becoming common in apartment buildings without a closed garage, allowing for sharing the available electrical connections to the grid. The multi-charger architecture allows using one or several common charging points by applying a mesh network of intelligent chargers orchestrated by a residential gateway. Managing the generated data load involves enabling data flow between several independent data producers and consumers. The data stream ingestion system must be scalable, resilient, and extendable.
- Intelligent beacon location and fingerprintingPublication . Martins, Pedro; Abbasi, Maryam; Sa, Filipe; Celiclio, Jose; Morgado, Francisco; Caldeira, FilipeThe complex way radio waves propagate indoors, leads to the derivation of location using fingerprinting techniques. In this cases, location is computed relying on WiFi signals strength mapping. Recent Bluetooth Low Energy (BLE) provides new opportunities to explore positioning. Indoor location identification plays a fundamental role as a business and personal level. At a business level, indoor location pinpointing where GPS signal is nonexistent is used to advise users and send push notifications (e.g., stores publicity, guide persons with special needs, or even for emergency evacuation). In this work is studied how BLE beacons radio signals can be used for indoor location scenarios, as well as their precision. The proposed study is performed inside the campus of Viseu Polytechnic Institute, using hundreds of students, each with his smart-phone, as proof of concept. Experimental results show that BLE allows having less than 1.5 meters error approximately 90% of the times.
- Beacons positioning detection, a novel approachPublication . Morgado, Francisco; Martins, Pedro; Caldeira, FilipeRecent Bluetooth Low Energy (BLE) beacons provide new opportunities to explore positioning. Beacon positioning determination using current approaches is supported by pre-calculated formulas, for generic beacons, whereas the position can be accurately estimated with a low error up to a small distance; or based on fingerprinting the signal for the given space. In both cases, the accuracy variate depending on hardware specifications and other conditions such as beacon brand, wrap material, temperature, wind, location, surrounding interference, battery strength, among others. This paper introduces a method for beacon-based positioning, based on signal strength measurements at key distances for each beacon. This method allows for different beacon types, brands, and conditions. Depending on each situation (i.e., hardware and location) it is possible to adapt the distance measuring curve to minimize errors and support higher distances, while at the same time keeping good precision. Moreover, this paper also presents a comparison with traditional positioning method, using formulas for distance estimation, and then position triangulation. Performed tests took place at the library of the campus of the Polytechnic Institute of Viseu. Experimental results show that the proposed position technique has 13.2% better precision than triangulation, for distances up to 10 meters.
- A Ghost Cell-Based Data Structure for Multiresolution MeshesPublication . Rodrigues, Rui; Morgado, José Francisco; Silva, Frutuoso; Gomes, AbelMultiresolution meshes enable us to build representations of geometric objects at different Levels of Detail (LODs). We introduce a multiresolution scheme whose data structure allows us to separately re- store the geometry and topology of a mesh during the refinement process. Additionally, we use a topological criterion (not a geometric criterion, as usual in the literature) to quickly simplify a mesh, what seems to make the corresponding simplification algorithm adequate for real-time appli- cations such as, for example, on-line computer games.
- Trust and reputation management for critical infrastructure protectionPublication . Caldeira, Filipe; Monteiro, Edmundo; Simoes, PauloToday's critical communication technologies (ICTs) to deliver their services with the required level of quality and availability. ICT security plays a major role in CI protection and risk prevention for single and also for interconnected CIs were cascading effects might occur because of the interdependencies that exist among different CIs. This work addresses the problem of ICT security in interconnected CIs. Trust and reputation management using the policy-based management paradigm is the proposed solution to be applied at the CI interconnection points for information exchange. The proposed solution is being applied to the Security Mediation Gateway being developed in the scope of the European FP7 MICIE project, to allow information exchange among interconnected CIs.
- Design and implementation of a mediation system enabling secure communication among Critical InfrastructuresPublication . Castrucci, Marco; Neri, Alessandro; Caldeira, Filipe; Aubert, Jocelyn; Khadraoui, Djamel; Aubigny, Matthieu; Harpes, Carlo; Simoes, Paulo; Suraci, Vincenzo; Capodieci, PaoloNowadays, the increase of interdependencies among different Critical Infrastructures (CI) makes it more and more difficult to protect without using a systemic approach that considers a single infrastructure as part of a complex system of infrastructures. A strong collaboration among CI owners is required to avoid, or at least to limit the propagation of failures from one infrastructure to another and to put CI in safety mode. The key element enabling this required cooperation is the possibility for them to exchange relevant information related to the status of their infrastructures and to the services provided. In this paper, we present a middleware solution that allows CIs sharing real-time information, enabling the design and implementation of fault mitigation strategies and mechanisms to prevent the cascading phenomena generated by the failure propagation from one infrastructure to another.