@Aljoscha

I think we could implement deleting messages with current messages/feeds

That is an interesting proposal, but it does rely on fully trusting your replication peers, something that both Dominic and I are reluctant to do.

I don't think it should require fully trusting replication peers. Replication peers would be able to deny sending you messages from someone's feed - but they can do that already. Decisions would be local as to whether to skip a sequence number when requesting a feed if you expect a banned message at that sequence number (vs. keep trying to replicate it, waiting for a peer who doesn't consider it banned to send it to you), and whether to drop a received message if it is a banned one, and whether to omit sending a message that is banned. The interesting part is which messages to consider banned - which would be common to any such implementation for message banning, I think. I would imagine people could publish a message identifying a message to ban, and the reason, and the sequence number and previous message id. Then you could consider a message to be banned based some configurable heuristic including number of people who declared it banned, your follow-hops to them, etc.

Thanks for clarifying the bit about message id hashing. Being able to calculate the message id with the hash of the content instead of the content itself seems like a good idea to me for the next version, to help enable seperate replication.