Sorry, I was speaking imprecisely and off the top of my head. You of course have to have multiple certificates, but the point is all that is necessary is for all of the certificates to be sent to the browser and for the browser to check them. It's entirely a question of browser<->server interaction.
You can get all of those certificates for the same hostname and key without any of the authorities even knowing the others exist.
Of course there are technical changes necessary in the browsers and web servers, but that's not the point. The SSL trust model is flawed and needs to be fixed, there are precious few options that won't involve some technical changes.
Comments
Sorry, I was speaking imprecisely and off the top of my head. You of course have to have multiple certificates, but the point is all that is necessary is for all of the certificates to be sent to the browser and for the browser to check them. It's entirely a question of browser<->server interaction.
You can get all of those certificates for the same hostname and key without any of the authorities even knowing the others exist.
Of course there are technical changes necessary in the browsers and web servers, but that's not the point. The SSL trust model is flawed and needs to be fixed, there are precious few options that won't involve some technical changes.