Re: [anti-spam-wg@localhost] I wrote a spam filter in Perl
- Date: Thu, 28 Aug 2003 13:32:15 -0700
At 10:19a +0200 08/23/2003, Gert Doering didst inscribe upon an
electronic papyrus:
Hi,
On Fri, Aug 22, 2003 at 10:35:59PM -0700, Walter Ian Kaye wrote:
> Should I sell it to ISPs? To individuals?
> Since it's Perl code, not compiled binary, how can I protect it?
Just make it open-source and sell consulting :-)
Cool idea... I could even appoint affiliate consultants in other
geographic regions and list them on my Web site. I like win-win
solutions. :D
At 12:32p +0200 08/23/2003, pna.lists didst inscribe upon an
electronic papyrus:
1) English-like syntax rules file is cool, but is it flexible enough? Does
it still filter spam when the spammers write V1arga instead of Viagra?
It supports regular expressions, so it can catch eye/one/ell substitutions.
It won't predict *every* misspelling, because that would near infinity.
2) You may want to start doing pilot projects with (fre)email providers,
hosting companies and the ASP's
3) Have you measure the false positive and false negative results?
I've only had one false positive, because someone who always sent
plain text unexpectedly sent multipart/alternative; now they're in my
whitelist.
As for false negative, I have yet to figure out how to catch the
Nigerian-style messages. Most of the incest spam goes to a retired
address so I catch 'em that way, but I don't know how else to
identify those either.
4) There *are* some Perl compilers available - it depends on the platform
you are using / targeting
5) You may want to try some Perl obfuscators
Thanks!
-Walter
having a ton of fun watching 90% of spam automatically destroyed :D