[KayEss]

I was wondering what happens if you skip the SNI bit and just rely on the Host header in the data. Does that work?

[andreareina]

That's called "domain fronting", the major cloud providers disallow it and enforce that the Host header must match the SNI.

[yardstick]

This is likely the major reason why China has not yet blocked the major cloud providers. As soon as they allow ESNI/domain fronting, all bets are off as to what China will block.

[lostmsu]

They explicitly started doing this after Telegram used domain fronting to work around Russian censorship, which caused large chunks of AWS and GCP addresses to be blocked in Russia.

[richardwhiuk]

You can only do that if you can present a single valid certificate for all of the hosts behind the IP address.