Quote from: franky1 on December 13, 2015, 02:21:13 AM

Quote from: RoadTrain on December 13, 2015, 02:04:12 AM

Quote from: jbreher on December 13, 2015, 01:50:11 AM

Quote from: RoadTrain on December 12, 2015, 09:29:13 PM

Fraud proof is simply some compact data telling you that Bitcoin rules were violated. For many of the rules we can create compact proofs that they were violated.

Nope. Still not getting it. A block with all associated signatures already contains everything needed to determine whether or not it is fraudulent.

It does, but not everything can be proven fraudulent compactly at the moment, in a way compatible with lightweight clients. Fraud proofs are allowing for a lite client to be aware of bad blocks without fully downloading and verifying them.

By fully verifying the blockchain you are proving that it's valid (good). By using fraud proof you are proving that something is invalid (bad). Notice the difference.

no... because full nodes make blocks (via mining pools ofcourse).. and if other users with full nodes see a invalid tx/block.. they ignore it, dont relay it.. end of
the real stupid thing would be to relay a tx/block knowing its bad/wrong..

its a simple concept.

imagine bank notes.. someone hands you a hand written piece of paper with scribbles on it.. you throw it in the bin and tell the person who created to go screw themselves.. you dont accept it. mark it as counterfeit and then hand it out to the next customer..

The default policy is already not to relay invalid data. But it doesn't help under adversarial circumstances. It doesn't help if there's miner collusion, and you are getting invalid data from them and have no means to know it's invalid. It doesn't help if they are relaying invalid data to you on purpose.

SW with these modifications allows for a more scalable and safe lite node approach, where you verify (perhaps randomly) some percentage of data.