At 10:28 PM 9/16/04 +0200, Hadmut Danisch wrote:

Because PKC works for this Alice&Bob communication scheme. If you connect to a web server, then what you want to know, or what authentication means is: "Are you really www.somedomain.com?" That's the Alice&Bob model. SSL is good for that.

What makes you think verislime or other CAs are authenticating? You can't sue them, they are 0wn3d by a State (and so can issue false certs, just like States issue false meatspace IDs), etc.

If I send you an encrypted e-mail, I do want that _you_ Ed Gerck, can read it only. That's still the Alice&Bob model. PGP and S/MIME are good for that.

What makes you think that EG is a physical entity, if you haven't met him and learned to trust him through out of band channels?

The sender of an e-mail does not need to pretend beeing a particular person or sender. Any identity of the 8 (10?) billion humans on earth will do it.

What makes you think that, given 1e10 humans, there are 1e10 identities? Ie, why do you think there is a one-to-one mapping?

PKC is good as long as the communication model is a closed and relatively small user group. A valid signature of an unknown sender has at least the meaning that the sender belongs to that user group.

PKC is only as good as the means by which you obtain the public key. A server, a CA, are all worthless. The emperor has no clothes, get used to it.