RFC 4033:DNS Security Introduction and Requirement...
RFC-Ref

Authenticated Data


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... Checking Disabled (CD) and Authenticated Data (AD). In order to support the larger DNS ...


... name servers and its communication channel to them may choose to examine the setting of the Authenticated Data (AD) bit in the message header ...


... Wellington, B. and O. Gudmundsson, "Redefinition of DNS Authenticated Data (AD) bit", RFC 3655(-> 4035prop | 4034prop | 4033prop) ...



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