Could you elaborate a bit on what you mean by "meaningful"? As someone
who uses the DUL list as an anti-spam mechanism and who experiments
with turning it off and on, I can definitely say that turning it on
reduces the amount of spam I receive (on the order of about 100
messages a day).
Certainly. Here's another good spam-blocking strategy:
Turn off your SMTP listener.
Although highly effective at stopping spam, this method is not
meaningful.
Perhaps I should have used a better word, such as "selective", to
imply methods that are much more likely to stop spam than
non-spam. The MAPS DUL does not discriminate between spam or non-spam,
or even between users who have generated spam in the past and those
that do not. If you're a dialup user, you are automatically guilty of
spamming even if you can prove yourself innocent.
I recognize that it also harms folks like you for many of the reasons
you give. But I don't understand why you say it is not a meaningful
anti-spam mechanism.
Here's another way that the MAPS DUL is not meaningful. Comcast, which
just put all their cable modem IP address blocks in the MAPS DUL, says
that if you upgrade to one of their expensive commercial services you
can get a block of static IP addresses instead of one dynamic
address. And those static addresses will not be placed on the MAPS
DUL.
So if all you have to do to evade a supposed anti-spam mechanism is to
pay some more money to your ISP, do you still consider that mechanism
to be "meaningful"? Or is it just a way for your ISP to cynically
profit from spam with a mechanism they claim to be anti-spam?
Phil