
>>> luke's server responds with a list of transaction IDs that contain "spam", and provides a "zero knowledge proof" that proves to knots nodes that those "spam" transactions are valid, without having to download them. >>> A "zero knowledge proof" solution, that proves transaction is valid without having to download the "spam" part of it, is an excellent idea. Every node operator can define their own definition of "spam" and choose the authoritative server(s) providing the list of txid containing the "spam". This will bring to life new competing full node implementations that will stay 100% compatible with current network protocol. #Bitcoin future is bright!