Re: [DNSOP] Fundamental ANAME problems

Olli Vanhoja <> Tue, 06 November 2018 08:23 UTC

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From: Olli Vanhoja <>
Date: Tue, 06 Nov 2018 09:23:14 +0100
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Subject: Re: [DNSOP] Fundamental ANAME problems
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> > The semantics is exactly like a CNAME + HTTP Redirect.
> The latter part is what I expected, and why I think it's a non-starter.
> HTTP Redirects cause the URI in the address bar to be changed.  A lot of
> the whole "CNAME at the Apex" issue arises because lots of marketing
> people don't want end users to have to type *or see* the www prefix.
> Those folks aren't going to stand for their nice clean "" URL
> getting replaced with the real CDN address in the address bar.

It's not only about what is shown in the address bar but how fast the
website will
start rendering something on the screen. Even resolving a CNAME may add a
proportionally big delay to the TTFB, it could take about the same time as
negotiation. In fact if you look at the DNS records some big Internet
they rarely use CNAMEs for www but instead you'll see an A record, that
be even backed by a proprietary ANAME solution.