Re: [TLS] SNI from CDN to Origin (was I-D Action: draft-ietf-tls-sni-encryption-08.txt)

Rob Sayre <sayrer@gmail.com> Wed, 09 October 2019 12:55 UTC

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From: Rob Sayre <sayrer@gmail.com>
Date: Wed, 9 Oct 2019 19:54:53 +0700
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To: Eric Rescorla <ekr@rtfm.com>
Cc: "Salz, Rich" <rsalz@akamai.com>, "TLS@ietf.org" <tls@ietf.org>
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Subject: Re: [TLS] SNI from CDN to Origin (was I-D Action: draft-ietf-tls-sni-encryption-08.txt)
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On Wed, Oct 9, 2019 at 7:51 PM Eric Rescorla <ekr@rtfm.com>; wrote:

>
> How would that work? The SNI is used by the server to determine what
> certificate to send. That's why it's sent in CH.
>

I understand why SNI is needed for IPv4 addresses.

But, if I have Cloudflare (or any CDN) configured for a domain, and the
origin is only available via IPv6, the need for a disambiguating SNI in the
ClientHello from CDN to Origin is not clear.

thanks,
Rob