From: cman@communities.com (Douglas Barnes)
Date: Sat, 28 Oct 1995 06:40:18 +0800
To: cypherpunks@toad.com
Subject: Re: newsweek oct 30 Levy digital cash article
Message-ID: <v02120d08acb716a45144@[199.2.22.120]>
MIME-Version: 1.0
Content-Type: text/plain



Vlad the Inhaler writes:
>
>you apparently didn't notice but there were some other posts on this
>list about writing down the random seed that a person used to generate
>the cash, and then being able to restore the cash somehow based on knowing
>the random seed, however privacy is sacrified in this case apparently.
>this with the Chaumian implementation, from what I understood.
>

I would not say that privacy is "sacrificed" if, in fact, Digicash
has implemeneted this "write down the original random seed" backup
method. Worst case scenario -- you write down the seed, and when the
police break down your door, they find that you've written it down.
Well, if things have progressed to that point, you're in pretty
serious trouble anyhow, and if you're expecting this to happen you
have a simple remedy -- back up & encrypt your wallet rather than
writing the seed down. Or, put the seed in a little text file,
encrypt the text file, and back it up.

I suspect, however, that this means that the Digicash wallet doesn't
pick up new bits of entropy to "groom" it's random state. Also, it
was unclear where this state came from, but it's hopefully not just
text entered by the user. (I could see getting the state from something
like keystrokes or mouse clicks, then having the user write down a
checksummed, error-corrected string as a preferred alternative.)