Super Testnet on Nostr: It works like onion messages. Before bolt12, by default, you send someone money by ...
It works like onion messages. Before bolt12, by default, you send someone money by creating a path to their node: Alice pays Bob to pay Carol to pay Dave to pay Edna to pay Filbert. Filbert's invoice tells Alice how to construct a path to his node, and consequently Alice can find Filbert's node on the network, and construct a path to him.
With bolt12, the default way to send money is by creating a paty to a "rendezvous" node: Alice pays Bob to pay Carol to pay Dave...but she doesn't know anything beyond that. Filbert's node is talking to Dave waiting for him to say "I've got a message for you, but I don't know who it's from." (But it's from Alice.) Filbert's node then decrypts/reads the message and tells Dave "you should have a payment from someone that is meant to come to me. Let's finish the route." And then they finish the route together (Dave -> Edna -> Filbert) and settle the payment.
By this method, Alice never learns where Filbert's node is on the network and does not know where she sent the money. Also, lightning payments are atomic, so this is all done without ever letting any routing node (Bob, Carol, Dave, or Edna) ever have custody of the funds. Each routing node can either forward the payment or cancel the payment, but not keep the payment for themselves.
With bolt12, the default way to send money is by creating a paty to a "rendezvous" node: Alice pays Bob to pay Carol to pay Dave...but she doesn't know anything beyond that. Filbert's node is talking to Dave waiting for him to say "I've got a message for you, but I don't know who it's from." (But it's from Alice.) Filbert's node then decrypts/reads the message and tells Dave "you should have a payment from someone that is meant to come to me. Let's finish the route." And then they finish the route together (Dave -> Edna -> Filbert) and settle the payment.
By this method, Alice never learns where Filbert's node is on the network and does not know where she sent the money. Also, lightning payments are atomic, so this is all done without ever letting any routing node (Bob, Carol, Dave, or Edna) ever have custody of the funds. Each routing node can either forward the payment or cancel the payment, but not keep the payment for themselves.