Comment by ekr____

This isn't correct.

There are two authentication properties that one might be interested in:

1. The binding of some real world identity (e.g., "Google") to the domain name ("google.com). 2. The binding of the domain name to a concrete Web site/connection.

The WebPKI is responsible for the second of these but not the first, and ensures that once you have the correct domain name, you are talking to the right site. This still leaves you with the problem of determining the right domain name, but there are other mechanisms for that. For example, you might search for the company name (though of course the search engines aren't perfect), or you might be given a link to click on (in which case you don't need to know the binding).

Yes, it is useful to know the real world identity of some site, but the problem is that real world identity is not a very well-defined technical concept, as names are often not unique, but instead are scoped geographically, by industry sector, etc. This was one of the reasons why EV certificates didn't really work well.

Obviously, this isn't a perfect situation, but the real world is complicated and it significantly reduces the attack surface.