Visible to the public Biblio

Filters: Author is Papadopoulos, Stavros  [Clear All Filters]
2020-04-13
Papachristou, Konstantinos, Theodorou, Traianos, Papadopoulos, Stavros, Protogerou, Aikaterini, Drosou, Anastasios, Tzovaras, Dimitrios.  2019.  Runtime and Routing Security Policy Verification for Enhanced Quality of Service of IoT Networks. 2019 Global IoT Summit (GIoTS). :1–6.
The Internet of Things (IoT) is growing rapidly controlling and connecting thousands of devices every day. The increased number of interconnected devices increase the network traffic leading to energy and Quality of Service efficiency problems of the IoT network. Therefore, IoT platforms and networks are susceptible to failures and attacks that have significant economic and security consequences. In this regard, implementing effective secure IoT platforms and networks are valuable for both the industry and society. In this paper, we propose two frameworks that aim to verify a number of security policies related to runtime information of the network and dynamic flow routing paths, respectively. The underlying rationale is to allow the operator of an IoT network in order to have an overall control of the network and to define different policies based on the demands of the network and the use cases (e.g., achieving more secure or faster network).
2017-08-22
Demertzis, Ioannis, Papadopoulos, Stavros, Papapetrou, Odysseas, Deligiannakis, Antonios, Garofalakis, Minos.  2016.  Practical Private Range Search Revisited. Proceedings of the 2016 International Conference on Management of Data. :185–198.

We consider a data owner that outsources its dataset to an untrusted server. The owner wishes to enable the server to answer range queries on a single attribute, without compromising the privacy of the data and the queries. There are several schemes on "practical" private range search (mainly in Databases venues) that attempt to strike a trade-off between efficiency and security. Nevertheless, these methods either lack provable security guarantees, or permit unacceptable privacy leakages. In this paper, we take an interdisciplinary approach, which combines the rigor of Security formulations and proofs with efficient Data Management techniques. We construct a wide set of novel schemes with realistic security/performance trade-offs, adopting the notion of Searchable Symmetric Encryption (SSE) primarily proposed for keyword search. We reduce range search to multi-keyword search using range covering techniques with tree-like indexes. We demonstrate that, given any secure SSE scheme, the challenge boils down to (i) formulating leakages that arise from the index structure, and (ii) minimizing false positives incurred by some schemes under heavy data skew. We analytically detail the superiority of our proposals over prior work and experimentally confirm their practicality.