Re: [DNSOP] DNS HTTPS/SVCB record type support in iOS 14

David Schinazi <> Fri, 25 September 2020 20:12 UTC

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From: David Schinazi <>
Date: Fri, 25 Sep 2020 13:12:25 -0700
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To: Tommy Pauly <>
Cc: dnsop WG <>, QUIC WG <>
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Subject: Re: [DNSOP] DNS HTTPS/SVCB record type support in iOS 14
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Hi Tommy,

Thanks for the announcement! It's really exciting to see this deployed in
the wild.
Clarification question: your email mentioned support for the HTTPS DNS
but it didn't mention when iOS makes those queries. For example, do you
this record every single time you perform A/AAAA queries? (in the context of
a Network.framework connection to port 443)


On Fri, Sep 25, 2020 at 12:59 PM Tommy Pauly <tpauly=> wrote:

> Hello DNSOP & QUIC,
> I wanted to provide an update that the production version of iOS 14, which
> shipped last week, includes support for sending HTTPS (SVCB) DNS queries
> (RR type 65) for applications using our system networking APIs.
> The implementation status has been updated here:
> For those with HTTP/3 QUIC deployments, this means that (when HTTP/3
> experimental support is enabled) iOS will use the ALPN indication in the
> HTTPS record to enable HTTP/3 prior to receiving an Alt-Svc indication. As
> previously noted on the DNSOP list, Cloudflare is already supporting
> publishing these records, and we’d encourage other server deployments that
> support QUIC to do the same.
> To note, this behavior is the same in the betas of macOS 11.
> Best,
> Tommy