[Cryptography] [ANNOUNCE] HashCash Digital Cash

[Patrick Chkoreff]

Ashish Gulhati wrote on 06/22/2017 03:34 AM:

> A vault can't block transactions, as it doesn’t see transactions, all it 
> sees are coins to be verified/spent. All transactions happen out of sight of
> the vault, when one user directly transfers coins to another.

Right.  So if I want to pay my friend Charles, I just send him one of my
coins directly and now he has a copy of it.  For his own peace of mind,
he should then exchange that coin with a new one at the vault though.
Is that correct?

By the way, how does my own wallet know that I've sent that coin off, so
it can mark it as no longer usable and I don't accidentally try to spend
it again?  I suppose that has something to do with the "Export" process.
 Am I right?

I would try it myself, but I've been busy with other things today.  I
did attempt to download the CPAN software though.  (What follows might
look like a complaint but it really isn't.)

I noticed your advice to apt-get install all the prerequisites first to
make it faster, but I decided to be cheeky and use the bare-bones "cpan
Crypt::HashCash" instead, just to see how terrible it would be.  You
see, I've been programming Perl for about 20 years now, and the CPAN
installer has always been a nail-biting experience that often craps out.
 Normally instead of using CPAN, I just go to each package individually,
do a "wget", unpack the tar.gz, and do the "make install" process manually.

So, sure enough, CPAN ran and ran for many many minutes, spewing its
test results and scary warnings about "LWP" and "deprecated" this and
that, but finally finished.  However, when I run "vault.pl", I see this:

  Can't locate Authen/TuringImage.pm in ...

It's OK though, I didn't expect the raw naked cpan install to work.
Again, I was just being cheeky and daring.  When I get some time I'll do
the apt-get install prerequisites and try it again.


Oh, I'm also curious how you managed to do blinding with Elliptic Curve
cryptography.  I've seen one old paper on the subject, but haven't
pursued it.  I've been intending to try blinding operations using DJB's
"TweetNaCl" some day.


-- Patrick