1. Fireflies: Scalable Intrusion-Tolerant Overlay Networking Robbert van Renesse and Maya Haridasan, Cornell University Håvard Johansen, Tromsø University, Norway André Allevana, University of Waterloo, Canada

2. Overlay Networks gaining in popularity Internet Multicast Routing Resilient Routing Content-based Routing Important additional functionality without changing Internet: Fragile, insecure routes Nodes easily “eclipsed”  No good for secure applications DHTs often used, but:

3. Fireflies Structure MembershipGossip Pinging Set Reconciliation Deliver within  Accuse and rebut Monitor & Suspect Exchang e diffs EACH COMPONENT IS PROBABILISTIC 2t + 1 virtual rings: t chosen such that each member has no more than t byzantine predecessors with high probability Each member monitors its 2t + 1 successors 4 protocol components

4. Partial view gossip with connections Erdös & Rényi: if probability of link is high enough, graph will be connected with high probability Chung & Lu: such a graph will have logarithmic diameter #members accusation rate (accs/sec) Bandwidth (bytes/sec) PlanetLab Experiment