Comment by miladyincontrol
1 day ago
IP addresses arent valid for the SNI used with ECH, even with TLS. On paper I do agree though it would be a decent option should things one day change there.
1 day ago
IP addresses arent valid for the SNI used with ECH, even with TLS. On paper I do agree though it would be a decent option should things one day change there.
I think that would have been an alternate present rather than a plausible future.
ECH needs for the outer (unencrypted) SNI to be somewhat plausible as a destination. For ECH GREASE what happens is that this outer SNI was real, what looks like the encrypted inner ECH data is just random noise.
For non-GREASE ECH we want to look as much like the GREASE as we can, except that it's not noise that's the encrypted payload with a real inner SNI among other things.