[dns-operations] Signaling client protocol to authority

[Paul Vixie]

> From: "Patrick W. Gilmore" <patrick at ianai.net>
> Date: Sun, 16 Jan 2011 13:46:26 -0500
> 
> The problem is end users who have no v6 connectivity ask for quad-A,
> and they do it over v4.

then they should stop doing that.

> As I explained earlier, if they ask for a quad-A over v6, it is far
> more likely they can actually reach the web server over v6.

getting from where we are to an all-ipv6 world is going to be hard for
a lot of people but it's where we are going and i'd like very much to
stop messing around with half measures on getting there.

and the converse case does not obtain, anyway.  those who ask for AAAA
over ipv4 do not nec'ily lack ipv6 connectivity they probably just got
a bunch of ipv4-only recursives assigned to them in dhcp.  those who
ask for A first and then AAAA likewise aren't predictably lacking in
ipv6 connectivity.  we should not be making assumptions about the 
connectivity of a stub based on what questions they ask or using what
protocol.

everybody just please add AAAA RR's to their web properties, and client
side vendors please just stop asking for AAAA RR's you cannot reach.