RFC 2505:Anti-Spam Recommendations for SMTP MTAs
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query


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... By this we mean the name returned from the DNS in response to a PTR query (.IN-ADDR.ARPA), i.e. when an IP address is translated to a ...
... One must not forget the increased amount of DNS queries which might result in problems for the DNS server itself to cope with ...
... DNS server in use, e.g. how it verifies that incoming responses correspond to outstanding queries, to minimize the risk for such attacks. ...



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