RFC 2065:Domain Name System Security Extensions
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concatenation


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... SIG resource record at the end of the reply which digitally signs the concatenation of the server's response and the resolver's query. ...


... where "|" is concatenation, RDATA is all the RDATA fields in the SIG ...
... algorithm documented in RFC 1321, "|" is concatenation, "e" is the private key exponent of the signer, and ...



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