Journals

T. Giannetsos and T. Dimitriou, “LDAC: A Localized and Decentralized Algorithm for Efficiently Countering Wormholes in Mobile Wireless Networks”, International Journal of Computer and System Sciences, 2013.    [BibTex]

Short Abstract:  In this work, we present a novel lightweight countermeasure for the wormhole attack, called LDAC (Localized-Decentralized Algorithm for Countering wormholes). It is completely localized and works by looking for simple evidence that no attack is taking place, using only connectivity information, as implied by the underlying communication graph. LDAC is not confined to static networks but extends naturally to dynamic and even mobile ones. Rigorous arguments that prove the correctness of the algorithm are coupled with detailed performance evaluation along with an implementation on real sensor devices that demonstrates its efficiency in terms of memory requirements and processing overhead.

A. Michalas, T. Dimitriou, T. Giannetsos, N. Komninos and N. R. Prasad. “Vulnerabilities of Decentralized Additive Reputation Systems Regarding the Privacy of Individual Votes”, Published in the Wireless Personal Communications journal, Volume 66, Number 3, July 2012.    [BibTex]      Distinguished journal paper

Short Abstract: In this paper, we focus on attacks and defense mechanisms in additive reputation systems. We start by surveying the most important protocols that aim to provide privacy between individual voters. Then, we categorize attacks against additive reputation systems considering both malicious querying nodes and malicious reporting nodes that collaborate in order to undermine the vote privacy of the remaining users. To the best of our knowledge this is the first work that provides a description of such malicious behavior under both semi-honest and malicious model. In light of this analysis we demonstrate the inefficiencies of existing protocols.

T. Giannetsos, T. Dimitriou and N. R. Prasad. “People-centric Sensing in Assistive Healthcare: Privacy Challenges and Directions”. Security and Communication Networks Journal, 2011.    [BibTex]

Short Abstract:  In this paper, we discuss our vision for people-centric sensing in assistive healthcare environments and study the security challenges it brings. This highly dynamic and mobile setting presents new challenges for information security, data privacy and ethics, caused by the ubiquitous nature of data traces originating from sensors carried by people. We aim to instigate discussion on these critical issues because people-centric sensing will never succeed without adequate provisions on security and privacy. To that end, we discuss the latest advances in security and privacy protection strategies that hold promise in this new exciting paradigm. We hope this work will better highlight the need for privacy in people-centric sensing applications and spawn further research in this area.

T. Giannetsos, T. Dimitriou, I. Krontiris and N. R. Prasad. “Arbitrary Code Injection through Self-propagating Worms in Von Neumann Architecture Devices”. Computer Oxford Journal for the Algorithms, Protocols, and Future Applications of WSNs Special Issue, Volume 53, 2010.    [BibTex]

Short Abstract: In this paper, we demonstrate how to execute malware on wireless sensor nodes that are based on the Von Neumann architecture. We achieve this by exploiting a buffer overflow vulnerability to smash the call stack and intrude a remote node over the radio channel. By breaking the malware into multiple packets, the attacker can inject arbitrarily long malicious code to the node and completely take control of it. Then we proceed to show how the malware can be crafted to become a self-replicating worm that broadcasts itself and infects the network in a hop-by-hop manner. To our knowledge, this is the first instance of a self-propagating worm that provides a detailed analysis along with instructions in order to execute arbitrary malicious code.