Another field in the DNS

John Levine johnl at
Tue Mar 3 11:51:32 CET 2009

>I just tried and got back in the question section, and
>pointers to that same name in the answer section. If a server wanted
>to send back an answer with different upper/lower casing, would it be
>wise to do that in the answer section? Or would it be better to do it
>in the additional section?

Don't change the case in the answer -- people have observed that DNS
servers consistently preserve the case of the request in the response,
and are now using randomized case in DNS lookups as a heuristic to
deter poisoning attacks.

I don't have an opinion about the wisdom of adding extra stuff to the
additional section, although I share concerns about how well existing
DNS lookup and cache software would handle it.

John Levine, johnl at, Primary Perpetrator of "The Internet for Dummies",
Information Superhighwayman wanna-be,, ex-Mayor
"More Wiener schnitzel, please", said Tom, revealingly.

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