On Fri, Nov 14, 2008 at 3:19 AM, <michael(_dot_)dillon(_at_)bt(_dot_)com>
- DNSBLs break email deliverability.
(DNSBL technology in fact ensures that the email sender is notified
if an email is rejected, unlike Bayesian filters/content filters
which place spam in the user's trash without notifying the senders)
This still breaks deliverability.
- DNSBLs "sit in the middle of an end-to-end email transaction"
(see: http://www.spamhaus.org/dnsbl_function.html for
There is a diagram under Rights of a Sender vs Rights of a Receiver
which shows that the DNSBL modifies the behavior of the Receiving
mail server. This is what I mean by "sitting in the middle of an
end-to-end (sender to recipient) email transaction.
At the desire of the receiving mail site's administrator.
And is not unique to DNSBLs. Any sort of spam filtering modifies the
behavior of the receiving mail server.
Al Iverson on Spam and Deliverability, see http://www.spamresource.com
News, stats, info, and commentary on blacklists: http://www.dnsbl.com
My personal website: http://www.aliverson.com -- Chicago, IL, USA
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