I think that in both cases, Usenet serves as an example (and an old one) of how the problem might be solved. At worst, what happens is that messages arrive in

I think that in both cases, Usenet serves as an example (and an old one) of how the problem might be solved. At worst, what happens is that messages arrive in a different order than they were posted, hence the importance of "References" headers and quoting posts (the rest becomes a UI problem). Digital signing defeats forgery (if the network fractures, then your signed messages will only appear in one of the pieces of the network until the fracture is resolved), and encryption and mix-nets protect privacy. So let's say you wanted to build a social networking system on top of Usenet. Here is one approach: * Use attribute-based encryption to distribute keys to your friends; this allows you to control who can see the posts you make * To post, you encrypt, sign, and encrypt again your message; then you send it through a mix-net to alt.anonymous.messages * Your friends all download from alt.anonymous.messages, decrypting those messages they can decrypt. Your signature tells them who made the post, and ABE ensures that only those who have permission to see the post can decrypt it. You can imagine extensions for commenting on posts, or creating groups, etc. You can also see that Usenet is not really relevant -- any P2P broadcast system could be used.