Date Added: May 2011
A wide range of distributed applications requires some form of confidential communication between groups of users. In particular, the messages exchanged between the users and the identity of group members should not be visible to external observers. Classical approaches to confidential group communication rely upon centralized servers, which limit scalability and represent single points of failure. In this paper, the authors present WHISPER, a fully decentralized middleware that supports confidential communications within groups of nodes in large-scale systems. It builds upon a peer sampling service that takes into account network limitations such as NAT and firewalls.