From: dmandl@lehman.com (David Mandl)
Date: Wed, 23 Feb 94 09:19:13 PST
To: rondavis@datawatch.com
Subject: Re: Mac encryption
Message-ID: <9402231713.AA28724@disvnm2.lehman.com>
MIME-Version: 1.0
Content-Type: text/plain


> From: Ron Davis <rondavis@datawatch.com>
> 
> > dmandl@panix.com said:
> >
> >Cypherpunks do have an interest in all forms of crypto, but there are
> >very good reasons why public key is more desirable than symmetric for "our
> >purposes."  This is at the very root of the crypto revolution and the
> >cypherpunk ethos.  Have you done the basic reading?  (That's a serious
> >question, not sarcasm.)
> 
>         Depends on what the required reading list for this group is.
>         I thought that our purposes were to promote the privacy of
>         individuals through the use of cryptography.  This can be done
>         in the contexts I talked about with symmetric as well as PK crypto.

The invention (discovery?) of public-key crypto changed the world, and
makes practical everyday use of crypto infinitely easier.  It also makes
the kinds of specific things cypherpunks are interested in much more
practical (or POSSIBLE).  If you correspond with hundreds of people on a
regular basis, including people you don't know and people you may send
something to once and never deal with again, it is impractical to say the
least to have to generate and exchange keys.  That's the basic argument.
Why was public key crypto invented at all?  Why are people interested in
using it?  Practically, it's really fundamentally different from symmetric
crypto, which is of very limited use in the situation we're all in now
(anonymous communication, the net, quick hit-and-run dissemination of
information, digital signatures, etc., etc.).  PGP also has the "web of
trust" structure built in.  This is worlds away from basic symmetric
crypto.

This is really basic stuff, so I'm hesitant to discuss it on the list.

>         Maybe I have the wrong idea about "our purposes", please correct me
>         if I'm wrong.

If you're relatively new to the list, try to get your hands on some of the
basic cypherpunk material, like tcmay's Crypto-Anarchy manifesto, the
cypherpunk articles in Wired or Whole Earth Review, etc.  There are many
different views represented on the list, but I think we all agree on the
significance and importance of pk crypto.

Symmetric is fine for hiding things from your boss.  PK is intended for
different purposes.

> >And of course, it does all the public-key encryption and key-management as
> >well.  A pretty incredible package, considering its size and cost.
> 
>         You're right its free.  If something is free you can't really complain
>         about it.  If it does anything its a bargan.

I didn't mean to insult PGP by claiming that it's worth the price ($0).  It's
actually worth much more.  I was just saying that for free it's an astounding
deal.

   --Dave.