Visible to the public Biblio

Filters: Author is Kolokotronis, Nicholas  [Clear All Filters]
2021-08-11
Mathas, Christos-Minas, Vassilakis, Costas, Kolokotronis, Nicholas.  2020.  A Trust Management System for the IoT domain. 2020 IEEE World Congress on Services (SERVICES). :183–188.
In modern internet-scale computing, interaction between a large number of parties that are not known a-priori is predominant, with each party functioning both as a provider and consumer of services and information. In such an environment, traditional access control mechanisms face considerable limitations, since granting appropriate authorizations to each distinct party is infeasible both due to the high number of grantees and the dynamic nature of interactions. Trust management has emerged as a solution to this issue, offering aids towards the automated verification of actions against security policies. In this paper, we present a trust- and risk-based approach to security, which considers status, behavior and associated risk aspects in the trust computation process, while additionally it captures user-to-user trust relationships which are propagated to the device level, through user-to-device ownership links.
2020-02-24
Brotsis, Sotirios, Kolokotronis, Nicholas, Limniotis, Konstantinos, Shiaeles, Stavros, Kavallieros, Dimitris, Bellini, Emanuele, Pavué, Clément.  2019.  Blockchain Solutions for Forensic Evidence Preservation in IoT Environments. 2019 IEEE Conference on Network Softwarization (NetSoft). :110–114.
The technological evolution brought by the Internet of things (IoT) comes with new forms of cyber-attacks exploiting the complexity and heterogeneity of IoT networks, as well as, the existence of many vulnerabilities in IoT devices. The detection of compromised devices, as well as the collection and preservation of evidence regarding alleged malicious behavior in IoT networks, emerge as areas of high priority. This paper presents a blockchain-based solution, which is designed for the smart home domain, dealing with the collection and preservation of digital forensic evidence. The system utilizes a private forensic evidence database, where the captured evidence is stored, along with a permissioned blockchain that allows providing security services like integrity, authentication, and non-repudiation, so that the evidence can be used in a court of law. The blockchain stores evidences' metadata, which are critical for providing the aforementioned services, and interacts via smart contracts with the different entities involved in an investigation process, including Internet service providers, law enforcement agencies and prosecutors. A high-level architecture of the blockchain-based solution is presented that allows tackling the unique challenges posed by the need for digitally handling forensic evidence collected from IoT networks.
2020-01-21
Kolokotronis, Nicholas, Brotsis, Sotirios, Germanos, Georgios, Vassilakis, Costas, Shiaeles, Stavros.  2019.  On Blockchain Architectures for Trust-Based Collaborative Intrusion Detection. 2019 IEEE World Congress on Services (SERVICES). 2642-939X:21–28.
This paper considers the use of novel technologies for mitigating attacks that aim at compromising intrusion detection systems (IDSs). Solutions based on collaborative intrusion detection networks (CIDNs) could increase the resilience against such attacks as they allow IDS nodes to gain knowledge from each other by sharing information. However, despite the vast research in this area, trust management issues still pose significant challenges and recent works investigate whether these could be addressed by relying on blockchain and related distributed ledger technologies. Towards that direction, the paper proposes the use of a trust-based blockchain in CIDNs, referred to as trust-chain, to protect the integrity of the information shared among the CIDN peers, enhance their accountability, and secure their collaboration by thwarting insider attacks. A consensus protocol is proposed for CIDNs, which is a combination of a proof-of-stake and proof-of-work protocols, to enable collaborative IDS nodes to maintain a reliable and tampered-resistant trust-chain.