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0 sats \ 4 replies \ @BitcoinFoqus 18 Jun 2023 \ on: Daily discussion thread
Can someone please explain to me how offline payments with lightning works? I’ve seen two videos on Twitter, one with a card and one recently with a ring. Just wondering conceptually how something like that even works.
I believe this is how it works ..
- one of the participants has to be online
- the offline device sends the online device a LNURL
- the online device makes a request to using LNURL
- if the online device is paying, it does a lnurl-pay
- if the online device is receiving, it does a lnurl-withdrawal
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Ok, sounds like I need to learn how lnurl works.
If the online receiving device does lnurl-withdrawal, how does the sender authorize withdrawal of the sats? Or is it pre-authorization and then it’s authorized or signed or whatever when the user next gets online?
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iirc it requires entering a pin on the online receiving device
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Yeah, it's similar to a QR code but with NFC.
The link goes to the server, ideally controlled by you and not a company, and there you can setup anything you want to allow, say a maximum of sats, etc.
Boltcards are ideal for this. Note that you don't need to have an account with them to buy or use the card. And they ship worldwide, they are nice cards.
You can create your own open source boltcard server here
Create and host contactless payment cards using bitcoin over the lightning network
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