https://www.taler.net/

“privacy friendly online transactions”

I came across this and it’s looks interesting it seems to have been out for a while and seems to work well in the demo.

it sounds a bit like Blockchain, but it doesn’t seem to be. which i would think makes it more appealing because the setup was easy… but i can’t find any examples of it being used in the wild.

i was expecting to see more cases that used it when i saw there is funding for it from https://nlnet.nl/

i think this could be good to add into my app. but i wonder if it might not be a good idea if it hasnt established itself as reliable in the wild.

  • Kissaki@programming.devEnglish
    2·
    2 days ago

    I looked at Wikipedia; Taler then Blind signature, then looked for docs on GNU Taler where I didn’t immediately find any technical overview of how that works. Phind gave me a seemingly reasonable and understandable answer. (Surely sourced from somewhere.)

    When we multiply the original message by rere, sign it, and then multiply by r−1r−1, the blinding factors cancel out while preserving the signature.

    The success of this process relies on two critical properties:

    • The blinding factor must be relatively prime to N
    • The RSA keypair must satisfy the congruence relation red≡r(modN)red≡r(modN)

    The magic is that you can

    1. Apply a mathematical operation on your data
    2. Sign that data
    3. Revert/Invert the mathematical operation

    and the signature remains valid.

    It does sound like magic. But isn’t most of cryptography like that?

    There’s a python example in there as well, with such a calculation. I didn’t go through it though.