Hi Cezary, This is indeed the right place for such questions at the moment.
Cezary Dziemian <cezary.dziem...@gmail.com> writes: > 1. After LN starts, some group of users will use it, other not. If for > example, I would like to receive payment for coffee from some user, I don't > know if user uses LN or not. So, when someone buy something from me, do I > need to ask him what kind of payment he would like to use (LN or on-chain)? > The best would be, if I show him some qr code contains both public address > and LN invoice and his wallet could choose how to pay. But this cannot be > done this way, right? Yes, the transition is kind of painful. You can use a BOLT 11 QR code, which can contain a fallback address, but that still requires their app understand BOLT11 enough to extract it. If they understand the BIP70 payment protocol, it could include an alternate payment mechanism, but it seems nobody actually uses this. > 2. Lets imagine, that someone send me invoice. I send payment and someone > in the middle doesn't cooperate fast. My payment is waiting and until time > lock period lapse I don't know if my payment will be processed or not. What > to do then? This is the worst case, yes. It's actually two cases: one where the payment has failed, and one where it has succeeded and you don't know yet. If it's succeeded you'll get your goods (the recipient sees nothing wrong), so you don't care that you have to wait for the money to be deducted. If it hasn't, it's almost certainly going to fail, and you can either wait or try again with a new invoice (your wallet won't let to pay the same one twice unless it's definitely failed). For 1.1 you'd be able to reuse the same invoice safely, as long as the merchant was honest if it received two payments and rejects the second. > 3. Am I right that this decremental time lock is strongly related with > block confirmation time? If there would be currency that have very fast > confirmation time (like 5 seconds) then time lock period could be short > what can potentially solve problem described in paragraph 2? Somewhat, but not that low, because you still need a margin to turn around payments. In practice, if payments are so unreliable that you have to worry about this case, then something's horribly wrong! Cheers, Rusty. _______________________________________________ Lightning-dev mailing list Lightning-dev@lists.linuxfoundation.org https://lists.linuxfoundation.org/mailman/listinfo/lightning-dev