[Cryptography] Moving forward on improving HTTP's security

[James A. Donald]

On 2013-11-15 05:50, Tony Arcieri wrote:
> And what of other solutions like CT or Tack?

With CT, when your browser hits a site, gets a certificate, it needs to 
check if the certificate is in a CT file, which is cryptographically 
secured to be the same for everyone.

But, if you have check each newly encountered certificate in real time, 
why does it need the CA's signature?  (Other than to avoid threatening 
the CA business model.)

The social mechanism underlying CT is:

1. not everyone is allowed to write to the CT files.  It is a valuable 
privilege.

2. the cryptographic properties of CT files make it easy to detect 
misbehavior.

3. Denying someone the right to make further writes to the CT files is 
not disruptive, whereas trying to delete a CA is immensely disruptive, 
thus the threat to withdraw the privilege to write to CT files for 
misbehavior is far more credible than the threat to take a CA off the 
browser CA list.

This being so, why should we care about CA signatures?  If a certificate 
is in the CT files, that is far more credible evidence of being a good 
certificate than if it is signed by a CA.  Let us allow all domain name 
registrars to write to the CT files, conditional, of course, on correct 
behavior.