RFC2671/RFC6891 has
Z
Set to zero by senders and ignored by receivers, unless modified
in a subsequent specification.
which resulted in 2% of deployed nameservers just copying reserved
bits to the reply or 3% of nameservers not answering because a
reserved bit is set.
I suppose, but how many of the people who wrote the broken code would have
paid attention if it said YOU MUST SET THE BIT TO ZERO AND THEN IGNORE IT
YOU MORON.
Regards,
John Levine, johnl@xxxxxxxxx, Taughannock Networks, Trumansburg NY
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