Detection and mitigation of the eclipse attack in chord overlays

Distributed Hash Table-based overlays are widely used to support efficient information routing and storage in structured peerto- peer networks, but they are also subject to numerous attacks aimed at disrupting their correct functioning. In this paper we analyze the impact of the Eclipse attack on a Chord-based overlay in terms of number of key lookups intercepted by a collusion of malicious nodes. We propose a detection algorithm for the individuation of ongoing attacks to the Chord network, relying on features that can be independently estimated by each network peer, which are given as input to a C4.5-based binary classifier. Moreover, we propose some modifications to the Chord routing protocol in order to mitigate the effects of such attacks. The countermeasures can operate in a distributed fashion or assume the presence of a centralized trusted entity and introduce a limited traffic overhead. The effectiveness of the proposed mitigation techniques has been shown through numerical results.