Papers by Nikolaos Pitropakis
Machine Learning and Knowledge Extraction
A common privacy issue in traditional machine learning is that data needs to be disclosed for the... more A common privacy issue in traditional machine learning is that data needs to be disclosed for the training procedures. In situations with highly sensitive data such as healthcare records, accessing this information is challenging and often prohibited. Luckily, privacy-preserving technologies have been developed to overcome this hurdle by distributing the computation of the training and ensuring the data privacy to their owners. The distribution of the computation to multiple participating entities introduces new privacy complications and risks. In this paper, we present a privacy-preserving decentralised workflow that facilitates trusted federated learning among participants. Our proof-of-concept defines a trust framework instantiated using decentralised identity technologies being developed under Hyperledger projects Aries/Indy/Ursa. Only entities in possession of Verifiable Credentials issued from the appropriate authorities are able to establish secure, authenticated communicatio...
Review and Critical Analysis of Privacy-Preserving Infection Tracking and Contact Tracing
Frontiers in Communications and Networks
The outbreak of viruses have necessitated contact tracing and infection tracking methods. Despite... more The outbreak of viruses have necessitated contact tracing and infection tracking methods. Despite various efforts, there is currently no standard scheme for the tracing and tracking. Therefore, many nations of the world have developed their own ways where carriers of disease could be tracked and their contacts traced. These are generalized methods developed either in a distributed manner giving citizens control of their identity or in a centralized manner where a health authority gathers data on those who are carriers. This paper outlines some of the most significant approaches that have been established for contact tracing around the world. A comprehensive review on the key enabling methods used to realize the infrastructure around these infection tracking and contact tracing methods is also presented, and recommendations are made for the most effective way to develop such a practice.
A taxonomy and survey of attacks against machine learning
Computer Science Review
It's All in the Cloud: Reviewing Cloud Security
2013 IEEE 10th International Conference on Ubiquitous Intelligence and Computing and 2013 IEEE 10th International Conference on Autonomic and Trusted Computing, 2013
Cloud computing is gradually replacing traditional IT infrastructures. However, an important issu... more Cloud computing is gradually replacing traditional IT infrastructures. However, an important issue that has emerged through that revolution is the preservation of an adequate level of security for the infrastructure. Currently there are many researchers working in the area of cloud security and privacy protection, proposing several solutions that address the threats against cloud infrastructures. This paper provides a thorough review of the research work in the area presenting the solutions that have been proposed so far.
Towards an augmented authenticator in the Cloud
2014 IEEE International Symposium on Signal Processing and Information Technology (ISSPIT), 2014
Till All Are One: Towards a Unified Cloud IDS
Lecture Notes in Computer Science, 2015
It's All in the Cloud: Reviewing Cloud Security
2013 IEEE 10th International Conference on Ubiquitous Intelligence and Computing and 2013 IEEE 10th International Conference on Autonomic and Trusted Computing, 2013
ABSTRACT Cloud computing is gradually replacing traditional IT infrastructures. However, an impor... more ABSTRACT Cloud computing is gradually replacing traditional IT infrastructures. However, an important issue that has emerged through that revolution is the preservation of an adequate level of security for the infrastructure. Currently there are many researchers working in the area of cloud security and privacy protection, proposing several solutions that address the threats against cloud infrastructures. This paper provides a thorough review of the research work in the area presenting the solutions that have been proposed so far.
A practical steganographic approach for matroska based high quality video files
ABSTRACT Several steganographic algorithms have been proposed for protecting message secrecy agai... more ABSTRACT Several steganographic algorithms have been proposed for protecting message secrecy against unauthorized "reads". The most used method for hiding a message relies on embedding the secret message in Least Significant Bit (LSB) on the cover object. Though various digital formats have been proposed in literature to be used as cover objects, little attention has been paid on Matroska multimedia containers. In this work, we propose a practical method for applying steganography in these types of files. The proposed method consists of three distinct phases. The first one encrypts the hidden message, the second embeds it to the stego cover, while at the final step the stego cover is attached to a Matroska container. We tested our approach in various scenarios in order to evaluate the introduced overhead. Results shows that the use of several sizes for TXT and WAV files did not introduce considerable overhead. Depending on the file size the introduce overhead can be between 1 to 3 seconds.
Behaviour reflects personality: detecting co-residence attacks on Xen-based cloud environments
Cloud computing is gradually becoming the most popular option of Information Technology infrastru... more Cloud computing is gradually becoming the most popular option of Information Technology infrastructures. However, an important issue that has emerged through that revolution is the preservation of an adequate level of security for the infrastructure and the confrontation of malicious insiders. This paper proposes a methodology for detecting the co-residency attack in the kernel layer of a Xen-based cloud environment, using an implementation of the Smith–Waterman genetic algorithm. The proposed approach has been explored in a test bed environment, producing results that verify its effectiveness.
If you want to know about a hunter, study his prey: detection of network based attacks on KVM based cloud environments
Uploads
Papers by Nikolaos Pitropakis