RE: use case: CA acceptance (ACTION-74)

This issue I have with lots of these case studies is it describes these
things in terms that a typical user may not understand. It might be better
to describe this same one differently:

 

Alice has repeatedly visited her bank's web site. Everytime she visits our
bank's website she wants to be reassured that she is actually at the bank's
website and not a spoofed website. The bank's website can provide
information to the browser that indicates it is the bank's website and not a
spoof - this could include a combination of things: Certificated issued by a
CA that is consistent with past, IP addresses that are registered with that
URL, other things? If the browser checks for this combination of confirming
information, we need a solution that can:

1. Communicate to Alice that the site is valid and/or communicate to Alice
when the site is not valid and/or prevent invalid websites from coming up.

2. Have close to zero error in this communication (very little to no
instances where the browser is communicating false rejects or false accepts)
to prevent chicken little effect where user gets blocked or warned against
going to a real bank site, or where user gets assured it is the real bank
site when it is not.

3. Have this scheme still work against credible spoofing attacks (e.g.
man-in-the-middle, false links embedded in phishing emails)

 

Without a scheme that 

a. easily communicates to the user that they are at the same site they
always go to - the legitimate banks site

b. does not make enough mistakes to make this communications suspect and
untrustworthy

 

the users needs will not be reflected. And this needs to be done behind the
scenes unrelated to the users knowledge of CA's and certificates.

 

Dan Schutzer

 

-----Original Message-----
From: public-wsc-wg-request@w3.org [mailto:public-wsc-wg-request@w3.org] On
Behalf Of Thomas Roessler
Sent: Tuesday, January 09, 2007 7:44 PM
To: WSC WG
Subject: use case: CA acceptance (ACTION-74)

 

 

Another interaction.

 

Alice visits a bank's web site.  The certificate of that site is

issued by a CA that is not part of the set of root certificates that

Alice's browser trusts.  Alice is asked whether she wants to accept

this certificate.

 

Motivates: Practices for metainformation about CA certificates. 

 

Cheers,

-- 

Thomas Roessler, W3C  <tlr@w3.org>