Is it possible, for an other client, to 'trust' a client in a network

Question

I'm considering a problem in which a node lives in a network of many nodes. Nodes come and go. Each new node is spawned from an other (trusted) node (at least I could do that). Data is being transmitted between the nodes. No central authority exists.

Is it possible for a receiving node to know that the transmitting node is trusted? I'm looking for all sorts of attack vectors. The server running the node could be compromised. Man in the middle attacks? How does Bittorrent prevent malicious bytes entering the network (do they at all)? Could public/private encryption play a role?

Answer 1

Try looking into PGP, which uses the 'web of trust' concept. It sounds to me like that's what you're looking for.