Re: [perpass] Web-of-trust CAs

[Phillip Hallam-Baker <[e-mail]>]

On Mon, Oct 21, 2013 at 2:58 PM, DataPacRat <[e-mail]> wrote:

> I've just posted a new version of a draft for an extension to the
> current vCard format, "Signed vCards" [1]. The general idea is to use
> existing encryption techniques to turn an existing format for
> "identity description" into one for "identity authentication",
> including non-email-based identifiers, change of identifiers over
> time, publication and revocation of keys, and so forth.
>
> The reason I'm putting all of this together is that, after finding out
> just how brittle the current Certificate Authority system is, I wanted
> to have a replacement that was much mushier and resistant to root-CA
> hijacking, possibly based on some form of web-of-trust. I'm currently
> trying to teach myself enough about webfist [2] to see if it can be
> adapted for the purpose, likely by replacing its current DKIM-based
> authentication system. My thought is that if that can be made to work,
> then it may be feasible to try combining Signed vCards with CA-style
> certificates.
>
> There's also the possibility that I'm completely deluded about the
> whole approach. I'm not an expert in the field; I'm just trying to
> find a solution that's within my meager skills. So I'm hoping to evoke
> as much feedback and constructive criticism as I can. Since swapping
> out hierarchical CAs for a system more resistant to a subpoena attack
> would seem to help reduce pervasive monitoring, this list seems a
> worthwhile place to discuss it.
>

I think you need to work out how to evaluate how trust in the Web of Trust
is evaluated:

http://tools.ietf.org/html/draft-hallambaker-prismproof-trust-00

You can accuse the CA system of being 'brittle' but so is Web of Trust once
you get past the keys that you signed directly yourself.


Putting the key in a vcard only addresses one part of the problem, you need
to know whether you have the right vcard. An attacker that can knock over a
CA will have no trouble knocking over a simple vcard scheme either.

To replace that system you have to show that what you propose as a
replacement is actually stronger and that it is not susceptible to
sovereign control by a single government (at minimum, some of us are not
going to be any more happy with a group of governments acting in concert
unless you can assure us that they will not collude).


Where vcard is supported, it makes a fine mechanism for converting a key
identifier to a key. It is a less good mechanism for establishing trust in
a key which is what most of us see as the hard part.

-- 
Website: http://hallambaker.com/