Is there a Brands certificate reference implementation?

[An Metet]

Steve Furlong writes:
> Does anyone know of a reference implementation for Stefan Brands's
> digital certificate scheme? Alternatively, does anyone have an email
> address for Brands so I can ask him myself? (I haven't gotten anything
> back from ZKS's "contact us" address. But I don't know if Brands is
> still at ZKS.)

I will give you some pointers, but in exchange, Steve Furlong, you are
commanded to fix your cypherpunks archive at
http://archives.abditum.com/cypherpunks/index.html.  Despite your comments
on the web page as of February 13, none of the year 2004 links work.

You were already pointed to www.credentica.com, but it's not a very
informative page, is it?  Just a logo and a mailto.  Well, there is at
least some "hidden" content, at
http://www.credentica.com/technology/technology.html.  This has a paper
on Brands' technology and some information on his book.

In late 2002 I saw email from Brands with two return addresses,
brands at credentica.com and sbrands at videotron.ca.

As for implementations, there was library called NCash created by Swedish
student Niels MC6ller, described briefly at
http://www.lysator.liu.se/~nisse/hacks.html: "For my master of science
thesis, I implemented an offline digital cash system invented by Stefan
Brands. I haven't done anything about it since I got my MSc degree,
but the information about it is still available."

Well, the information isn't available, not there, anyway.  But if you
hunt around, you can find an announcement about NCash at
http://www.privacy.nb.ca/cryptography/archives/coderpunks/new/1998-02/0008.html
and the source code plus a technical paper are at
http://munitions.vipul.net/dolphin.cgi?action=render&category=09.

The good news is that the source code is available; the bad news is that
it is written in Pike.  No, I'd never heard of it, either.  Apparently it
is some Swedish language that was all the rage back in 1997.  However it
seems to be a pretty straightforward language, kind of Pythonish with a C
like syntax, so it might be feasible to port it to something more modern,
probably Python.  Or you could get the latest Pike interpreter and see
how well they've maintained backwards compatibility all these years.
According to the announcement, you'll also need the Pike crypto library,
but my guess is that it's been incorporated into the Pike package by
this time.

I'm sure you're aware that Brands credentials are patented up the wazoo.
Like Chaum, Brands prefers to publish his work in the pages of the
U.S. Patent Office.  That's why they're both so rich.