RSA blind signatures II

Hi!
My question in November/December on RSA blind signatures turned into a
discussion about Big Integer. I feel that  within the discussion my
initial point got lost. But also nobody rejected the idea to include
blind signatures within the Web Crypto API (I'm *not* asking for a
general Big Integer API). This is why I would like to underline the idea
with a few use cases. Chaum-based digital cash systems (e.g. opencoin)
use tokens to represent values. The user's wallet would be implemented
as a client-side JavaScript application to store the digital tokens
locally and not to expose them to (potentially insecure/untrusted)
servers. The system works without any account on a central server and
could store the tokens in the client exclusively. The wallet is used to
manage the tokens. This includes to top-up the pre-paid value in the
wallet or to deposit the amount to a bank account (which would not be
part of the very system). The wallet can be used to pay purchases done
in online shops directly within the webbrowser without the need for an
external application. The wallet could also transfer coins in a
peer-to-peer manner via WebRTC, webmail or other interfaces. Mobile apps
could be used to pay purchases during real physical shopping. All we
would need (for performance reasons) is RSA blind signatures being
supported by the Web Crypto API. Please let me know what you think.

Regards,
Stefan

Received on Monday, 21 January 2013 14:41:46 UTC