Security of peer-to-peer data storage
par Nouha Oualha, Telecom Paristech, Paris

Mardi 27 avril à 14h
Salle des Séminaires, LIRMM

Résumé
Self-organizing algorithms and protocols have recently received a lot of interest in mobile ad-hoc networks as well as in peer-to-peer (P2P) systems, as illustrated by file sharing or VoIP. P2P storage, whereby peers collectively leverage their storage resources towards ensuring the reliability and availability of user data, is an emerging feld of application. P2P storage however brings up far-reaching security issues that have to be dealt with, in particular with respect to peer selfishness, as illustrated by free-riding attacks. The continuous observation of the behavior of peers and monitoring of the storage process is an important requirement to secure a storage system against such attacks. Detecting peer misbehavior requires appropriate primitives like proofs of data possession, a form of proof of knowledge whereby the holder interactively tries to convince the verifier that it possesses some data without actually retrieving them or copying them at the verifier. We propose and review several proof of data possession protocols. We in particular study how data verification and maintenance can be handed over to volunteers to accommodate peer churn.