Filipe Caldeira

Prof. Dr. Filipe Caldeira

Informatics Department, Polytechnic Institute of Viseu, Viseu, Portugal
orcid

Research Focus & Metrics

Academic Career Length

24Years (2003-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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17 July 2020 in Electronics
Verified
Journal Article
Open access
PDF file
João HenriquesJoão Henriques
João Henriques
Filipe CaldeiraFilipe Caldeira
Filipe Caldeira
Tiago CruzTiago Cruz
Tiago Cruz
Paulo SimoesPaulo Simoes
Paulo Simoes
Computing and networking systems traditionally record their activity in log files, which have been used for multiple purposes, such as troubleshooting, accounting, post-incident analysis of security breaches, capacity planning and anomaly detection. In earlier systems those log files were processed manually by system administrators, or with the support of basic applications for filtering, compiling and pre-processing the logs for specific purposes. However, as the volume of these log files continues to grow (more logs per system, more systems per domain), it is becoming increasingly difficult to process those logs using traditional tools, especially for less straightforward purposes such as anomaly detection. On the other hand, as systems continue to become more complex, the potential of using large datasets built of logs from heterogeneous sources for detecting anomalies without prior domain knowledge becomes higher. Anomaly detection tools for such scenarios face two challenges. First, devising appropriate data analysis solutions for effectively detecting anomalies from large data sources, possibly without prior domain knowledge. Second, adopting data processing platforms able to cope with the large datasets and complex data analysis algorithms required for such purposes. In this paper we address those challenges by proposing an integrated scalable framework that aims at efficiently detecting anomalous events on large amounts of unlabeled data logs. Detection is supported by clustering and classification methods that take advantage of parallel computing environments. We validate our approach using the the well known NASA Hypertext Transfer Protocol (HTTP) logs datasets. Fourteen features were extracted in order to train a k-means model for separating anomalous and normal events in highly coherent clusters. A second model, making use of the XGBoost system implementing a gradient tree boosting algorithm, uses the previous binary clustered data for producing a set of simple interpretable rules. These rules represent the rationale for generalizing its application over a massive number of unseen events in a distributed computing environment. The classified anomaly events produced by our framework can be used, for instance, as candidates for further forensic and compliance auditing analysis in security management.

1 June 2021 in Future Generation Computer Systems
Verified
Journal Article
Closed access
LRLuis Rosa
Luis Rosa
Tiago CruzTiago Cruz
Tiago Cruz
MFMiguel Borges de Freitas
Miguel Borges de Freitas
PQPedro Quitério
Pedro Quitério
João HenriquesJoão Henriques
João Henriques
Paulo SimoesPaulo Simoes
Paulo Simoes

1 January 2024 in IEEE Access
Verified
Journal Article
Open access
João HenriquesJoão Henriques
João Henriques
Filipe CaldeiraFilipe Caldeira
Filipe Caldeira
Tiago CruzTiago Cruz
Tiago Cruz
Paulo SimoesPaulo Simoes
Paulo Simoes
The broadening dependency and reliance that modern societies have on essential services provided by Critical Infrastructures is increasing the relevance of their trustworthiness. However, Critical Infrastructures are attractive targets for cyberattacks, due to the potential for considerable impact, not just at the economic level but also in terms of physical damage and even loss of human life. Complementing traditional security mechanisms, forensics and compliance audit processes play an important role in ensuring Critical Infrastructure trustworthiness. Compliance auditing contributes to checking if security measures are in place and compliant with standards and internal policies. Forensics assist the investigation of past security incidents. Since these two areas significantly overlap, in terms of data sources, tools and techniques, they can be merged into unified Forensics and Compliance Auditing (FCA) frameworks. In this paper, we survey the latest developments, methodologies, challenges, and solutions addressing forensics and compliance auditing in the scope of Critical Infrastructure Protection. This survey focuses on relevant contributions, capable of tackling the requirements imposed by massively distributed and complex Industrial Automation and Control Systems, in terms of handling large volumes of heterogeneous data (that can be noisy, ambiguous, and redundant) for analytic purposes, with adequate performance and reliability. The achieved results produced a taxonomy in the field of FCA whose key categories denote the relevant topics in the literature. Also, the collected knowledge resulted in the establishment of a reference FCA architecture, proposed as a generic template for a converged platform. These results are intended to guide future research on forensics and compliance auditing for Critical Infrastructure Protection.

9 October 2020
Verified
Conference Paper
Closed access
RMRicardo Martins
Ricardo Martins
Filipe CaldeiraFilipe Caldeira
Filipe Caldeira
FSFilipe Sa
Filipe Sa
MAMaryam Abbasi
Maryam Abbasi
PMPedro Martins
Pedro Martins
The motivation for developing a self-service platform for employees arises precisely from the idea that in all organizations there are tasks that could be automated in order to redirect work resources to more important tasks. The proposed application consists of the development of a self-service platform, for personal information and scheduling tasks, aimed at the employees instead of all the solutions that are in the market that aim their platform to the Human Resources. We focus on the employers giving them more responsibility to make their own personal management like, change their personal info, book their vacations and other, giving to the Human Resources the tasks of managing all these actions made by the employers. At the end of the work, it is expected that the final solution to be considered as an example of success with regards to the theme of business automation and innovation, using the low-code application Outsystems to perform the full proposed application development.

16 June 2023 in International Journal of Critical Infrastructure Protection
Verified
Journal Article
Open access
João HenriquesJoão Henriques
João Henriques
Filipe CaldeiraFilipe Caldeira
Filipe Caldeira
Tiago CruzTiago Cruz
Tiago Cruz
Paulo SimoesPaulo Simoes
Paulo Simoes

9 August 2024 in Computers
Verified
Journal Article
Open access
PDF file
BNBruno Nascimento
Bruno Nascimento
RSRui Santos
Rui Santos
João HenriquesJoão Henriques
João Henriques
MBMarco V. Bernardo
Marco V. Bernardo
Filipe CaldeiraFilipe Caldeira
Filipe Caldeira
The shift from traditional monolithic architectures to container-based solutions has revolutionized application deployment by enabling consistent, isolated environments across various platforms. However, as organizations look for improved efficiency, resilience, security, and scalability, the limitations of container-based applications, such as their manual scaling, resource management challenges, potential single points of failure, and operational complexities, become apparent. These challenges, coupled with the need for sophisticated tools and expertise for monitoring and security, drive the move towards cloud-native architectures. Cloud-native approaches offer a more robust integration with cloud services, including managed databases and AI/ML services, providing enhanced agility and efficiency beyond what standalone containers can achieve. Availability, scalability, and security are the cornerstone requirements of these cloud-native applications. This work explores how containerized applications can be customized to address such requirements during their shift to cloud-native orchestrated environments. A Proof of Concept (PoC) demonstrated the technical aspects of such a move into a Kubernetes environment in Azure. The results from its evaluation highlighted the suitability of Kubernetes in addressing such a demand for availability and scalability while safeguarding security when moving containerized applications to cloud-native environments.