Le 25/08/2016 à 09:39, Jonas Schnelli via bitcoin-dev a écrit :
> (I think this case if not completely unrealistic):
> 
> What would happen, if a user gave out 21 addresses, then address0 had
> receive funds in +180 days after generation where address21 had receive
> funds immediately (all other addresses never received a tx).
> 
> In a scan, address0 would be detected at <address-birthday>+180 days
> which would trigger the resize+20 of the address-lookup-window, but, we
> would require to go back 180day in order to detect received transaction
> of address21 (new lookup-window) in that case.
> 
> Or do I misunderstand something?
> 
> 

That case is not unrealistic; a merchant might generate addresses that
are beyond their gap limit, and orders get filled at a later date.

In that case you will not get the same result when restoring your wallet
in a block-scanning wallet and in Electrum.

The lack of consideration for these cases is another issue with BIP44.