Stefan Wolfe (semi-OT)
Hi Mike
Well if I was creating a databases of addresses to SPAM (shudder!) I
would add on an SMTP engine that tries to connect to the host. If I got
a "550 mailbox not found" or something similar I wouldn't ever bother
trying again. It would be fairly easy then to have a known vs invalid
addresses. That along with (say) grabbing names from telephone books and
creating addresses with it for every domain that could be found would
build up a credible database to work with. Once the engine is perfected
a 95% failure rate is still a success..
I am sure there are institutions around that do this, if just to sell a
useful database to their customers. There are however far better and
more slimy programmers around than me!
I would suspect (but don't know) that ISP SPAM mitigation processes are
helping a lot nowadays. There have also been laws passed and ISP
acceptable use policies that are making things a little bit harder for
the SPAM creators... Most mail servers also have a lot of lookup/checks
that go on nowadays when they receive a connection. I think about half
at the place I work fail to connect because they are requesting relay,
have an invalid source domain/reverse lookup or something else that
prevents the chaff getting through. Those that do then have the SPAM
pattern filter trounce about 95% of.
Cheers Bob VK2YQA
Michael Coslo wrote:
I wonder just how much newsgroup harvesting is doen these days. It
wouldn't be very efficient.
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