>You can not apply any changes to existing blocks, as that will invalidate >their PoW.
The changes are not being applied to the block headers. Instead what is being modified is which transactions are sent with a block. For instance in Bitcoin if you delete a transaction when sending a block people will treat that block as invalid until they have the complete transaction set. However in MW cut-throughs means that there are legitimate reasons for not sending the entire block. Thus I can send a subset of the transaction set and everyone should be fine with it as long as it validates according the MW rules. >Can you show in detail what that final claimed utxo set looks like, how it is >consistent with the set of kernels of valid blocks, but different from the >result of processing all transactions from those blocks? Invalid block B1 (Tx1.out)<--(Tx2.in,Tx2.out) (Tx1.out)<--(Tx3.in,Tx3.out) Tx3 is deleted from B1, Tx5 is added in a new block such that the kernels balance out: Valid Block B1 (Tx1.out)<--(Tx2.in,Tx2.out) Valid Block B2 (Tx4.out)<--(Tx5.in, Tx5.out) On Thu, Mar 16, 2017 at 10:45 AM, John Tromp <[email protected]> wrote: > dear Ethan, > >> I can see how aggregate block is confusing terminology. I'm going to >> avoid using it in the future. >> >> What I meant was that the blocks B1+B2 are sent together and that >> possible cut-throughs have already been applied in both blocks. > > You can not apply any changes to existing blocks, as that will > invalidate their PoW. > I think what you're trying to do is construct some set of kernels and utxo set > that is claimed to summarize a valid block history when in actuality > there was no such history. > > Can you show in detail what that final claimed utxo set looks like, > how it is consistent with the set of kernels of valid blocks, but > different from the result > of processing all transactions from those blocks? > > Btw, one thing that confuses me in your argument is that you say that > cut-through can eliminate double spending. I don't see how that happens. > If tx1 double spends an output, then tx1 combined with later tx will still > doublespend that output. And tc1 combined with earlier tx will result > in earlier doublespends?! > > regards, > -John -- Mailing list: https://launchpad.net/~mimblewimble Post to : [email protected] Unsubscribe : https://launchpad.net/~mimblewimble More help : https://help.launchpad.net/ListHelp
