Dave Funk wrote:
> 553 5.1.8 <[EMAIL PROTECTED]>... Domain of sender address [EMAIL PROTECTED]
> does not exist
>
>You do a DNS resolvability check on each message that somebody tries to
>hand you, which is dependent upon an arbitratry remote DNS server.
>Based upon the results of that DNS lookup, you do reject mail.
>Thus I could argue that you do use DNSBL lists.
DNS blacklist maintainers are self-appointed and have varying
reputations that may be difficult to ascertain reliably. Few people
would recommend the risky idea of using a poorly-chosen DNS-based
blacklist.
Confirming that a sending domain really exists is a form of whitelist
query to the properly delegated authority for the domain. This
function is very different from DNSBL queries, and it would be better
if you didn't try to mislead people into thinking that they are
morally equivalent just because they both use the DNS.
:: Jeff Makey
[EMAIL PROTECTED]
