Re: Quic: the elephant in the room

Michael Thomas <> Mon, 12 April 2021 15:22 UTC

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Subject: Re: Quic: the elephant in the room
To: Andrew McConachie <>
Cc: "Salz, Rich" <>, Phillip Hallam-Baker <>, IETF Discussion Mailing List <>
References: <> <> <> <> <> <>
From: Michael Thomas <>
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Date: Mon, 12 Apr 2021 08:22:45 -0700
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On 4/12/21 3:36 AM, Andrew McConachie wrote:
> When looking at how one might implement DANE for HTTPS/TLS I don’t see 
> any reason to handle these things sequentially. You don’t have to 
> change TLS you just have to do things asynchronously. Query for TLSA 
> RRs at the same time as sending the TLS ClientHello, and kill the 
> connection setup when/if DANE validation fails. On the off chance that 
> the DNS actually takes longer than TLS, maybe delay sending data via 
> TLS until DNS responds. But I bet this almost never happens.
Correct. Better: you can do the TLSA request at the same time as the 
A/AAAA request speculatively. Plus if you've ever had a TLSA record for 
that domain, you know it's pretty likely you'll get a fresh one even if 
the last one is expired, so the speculation is minimal.