Re: The future will be easy to use

At 15:30 11/28/95 -0500, Carl Ellison wrote:
>BTW -- PGP currently lacks a way for me to note, when I sign a key, how it
>is that I trust that key (by personal meeting, by attribution, by message
>association, ...).  A signed attribute record would let me record that
>information for myself as well as for others.

There is more to this problem than how it is that I trust the key.  There
is also what I trust it for.  I just added a key to my key ring that I will
use for sending confidental data to a client site.  I trust that no one can
access the secret key who is not also inside their firewall.  However, the
key is on a multi-user system, so I do not trust that it is accessable to
only one person.  Since the data I intend to send will be publicly
available inside the firewall, I don't have to trust more than the
firewall.

It is hard to see how to record the information about how much I trust the
receipent's systems security.

Bill


-----------------------------------------------------------------
Bill Frantz                   Periwinkle  --  Computer Consulting
(408)356-8506                 16345 Englewood Ave.
frantz@netcom.com             Los Gatos, CA 95032, USA

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>Date: Wed, 29 Nov 1995 00:10:16 -0800
>From: frantz@netcom.com (Bill Frantz)

>It is hard to see how to record the information about how much I trust the
>receipent's systems security.

I don't see a computer-understandable way to do that either -- but you have
provided an example of a human-readable way in your prior paragraph:

>			     I just added a key to my key ring that I will
>use for sending confidental data to a client site.  I trust that no one can
>access the secret key who is not also inside their firewall.  However, the
>key is on a multi-user system, so I do not trust that it is accessable to
>only one person.  Since the data I intend to send will be publicly
>available inside the firewall, I don't have to trust more than the
>firewall.

You could sign a small message consisting of:

	a) that paragraph
	b) the subject public key (or its good-enough hash)
	c) your public key (or its good-enough hash)

with your key and let that attribute declaration do the job.  It would only
be humans who could interpret it, but in the end it's humans who need to.
The computer should be able to find and use (b) and (c) -- but leave the
human to interpret (a).

I grant that they'd rather let the machine do the thinking for them, but
that may not be possible -- especially at this time in the evolution of
generally available security, before we learn patterns to codify in
computer-understandable abbreviations.

 - Carl

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|Carl M. Ellison      cme@tis.com    http://www.clark.net/pub/cme	   |
|Trusted Information Systems, Inc.   http://www.tis.com/                   |
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