Attrition Defenses for a Peer-to-Peer Digital Preservation System

In peer-to-peer systems, attrition attacks include both traditional, network-level denial of service attacks as well as application-level attacks in which malign peers conspire to waste loyal peers' resources. We describe several defenses for the LOCKSS peer-to-peer digital preservation system that help ensure that application-level attrition attacks even from powerful adversaries are less effective than simple network-level attacks, and that network-level attacks must be intense, widespread, and prolonged to impair the system.