I am getting familiar of how ecash works. What I understand is that what you have on your device are multiple tokens of different denominations. So how can the Fedi app (which uses fedimint) send exact amounts offline? From what I understand the amount you can send ahould be composed from the available tokens. Which shouldn't always add up exactly to the required amount (unless you are lucky). How does that work?
72 sats \ 1 reply \ @anon 6 Nov
In offline e-cash, you still need an online mint to initially create and validate tokens. The mint provides the cryptographic signatures that make the tokens valid. When you go offline, you carry pre-signed tokens of various denominations. These tokens can be exchanged directly without real-time verification from the mint, but the mint must have originally signed and authorized those specific tokens. So "offline" really means peer-to-peer exchange using pre-validated tokens, but the initial token creation and validation still requires an online mint.
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Yes, exactly what i was talking about. But my tests on fedi app offline never say that you don't have the required tokens. No matter what value i type it never fails (offline that is). This seems very unlikely (unless the ballance is completely composed of 1 sat tokens of course).
It does not work that way. Yes it is true that it accumulates in your wallet but they are composed of SATS from different mints. You can send SATS from a specific token mints but if you want to send all of them in just one token mint you have to swap it. Swapping will incur a minimal fee. If your balance is composed of SATS from different mints you cannot send all them in a wallet of a specific token unless you trust it and want to swap it directly in your wallet.
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