AD
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... (CD) and Authenticated Data (AD). In order to support the larger DNS
message sizes that result from adding the DNSSEC RRs ...
... security-aware stub resolvers that data was found to be secure (using
the AD bit; see [RFC4035]).
...
... communication channel to them may choose to
examine the setting of the Authenticated Data (AD) bit in the message
header of the response messages it receives. The stub resolver can
...
... Wellington, B. and O. Gudmundsson, "Redefinition of DNS Authenticated Data (AD) bit", RFC 3655(-> 4035prop | 4034prop | 4033prop), November 2003. ...