Re: [dnsext] Fwd: RFC 2308 & RFC 4035

[Edward Lewis <[e-mail]>]

At 11:32 +1100 2/26/11, Mark Andrews wrote:
>Nothing worse than having asked for the AAAA record at 10:00 am.
>The zone administrator has to assume that AAAA queries will have
>been made prior to adding the AAAA records.  This will almost
>certainly be the case if there were A queries.

I think my question wasn't understood.

Do cache implementers use the fact that the proof of no A record 
coincidently shows there is also no AAAA record when processing a 
subsequent AAAA query.  (Meaning, there's no other entry for the AAAA 
alredy in the cache.)

If a cache does do this kind of proof by inference, what does the 
implementer think about the situation in which there is a "race 
condition" - that the proof of non-existence has been obviated by 
actions outside of it's sphere?  (Like the subsequent adding of the 
AAAA set in the authority.
-- 
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Edward Lewis
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