ur design for FeedTree, a system which replaces the polling component of news feeds with peer-to-peer multicast. The design, based on the Scribe group communication system, offers timely and efficient delivery of micronews by sharing the burden of delivery among cooperating peers in the network. Messages in the FeedTree system may optionally be cryptographically signed by the publisher to defend against spoofed content from malicious nodes.
http://trac.feedtree.net/project/wiki/FeedTree