On Tue, Dec 3, 2013 at 12:44 AM, Mike Hearn wrote: > PPv1 doesn't have any notion of fee unfortunately. I suppose it could be > added easily, but we also need to launch the existing feature set. > Lets bang out a merchant-pays-fee extension. How about: SPEC: optional uint64 allowfee tag number=1000 Allow up to allowfee satoshis to be deducted from the amount paid to be used to pay Bitcoin network transaction fees. A wallet implementation must not reduce the amount paid for fees more than allowfee, and transaction fees must be equal to or greater than the amount reduced. :ENDSPEC Rationale: we don't want wallet software giving users discounts-- sending transactions that are amount-allowfee without paying any fee. We also want to allow users to pay MORE in fees, if they need to (fragmented wallet, maybe, or big CoinJoin transaction) or decide to. PS: I think there was also consensus that the BIP72 request=... should be shortened to just r=... (save 6 chars in QR codes). Unless somebody objects, I'll change the BIP and the reference implementation code to make it so... -- -- Gavin Andresen