RE: Spam filters and mailing lists

From: Bil Herd (
Date: 2007-04-12 14:58:14

I own a small ISP and spam costs us a hugely inordinate amount of time
and resources.  We get up to a million messages in a day of which 25-30k
might be legitimate, then the rest have to be filtered and offloaded for
bounce tries (hey you have to try).  

Twice a week we have to tell Comcast that they can't just arbitrarily
block us because they get a lot of email from a single server address
here (we refer to it as our mail server) as one of their tactics is to
just count inbound emails and it's either a spammer or a competitor. I
think they also count spam bounces from them that we are trying to

Where once we had a single Pentium 90 serving 5,000 - 10,000 users I now
have an array of 7+ servers including a centralized database server so
our customer can all control their own spam settings, we have a scalable
front end because stupid-spammer-tricks ultimately can tie up any single
server in what becomes a denial-of-service  attack.  It takes the same
amount of servers whether we are supporting 1 or 5000 email boxes.

I used to use RBL's as they used to be a good tool, I stopped when they
became just one more source of someone wanting money from me annually (I
call that a tax on my business when depending on their attitudes)  We
hadn't ever tracked a complaint to the RBL's but that was a while back
and sometime you never know what you don't know in what email you aren't
receiving.  One day I blocked all email for Russia and New Zealand by
accident which seemed to fix the problem, but <ahem> broke a few things
such as people keeping in touch with their families. :(

The hardest metric does appear to be getting your email from your
mailing lists, we respond right away when our customers say they haven't
seen list mail as it's usually not their imagination and it usually is
something broken somewhere and more than half of the time it is related
to what our servers are doing in regards to spam (less problems with
this lately).

Moral of the story, yeah spammer suck and more, the cutesy articles
about how they are just grandmothers making a living neglect to mention
their vandalism and trespass. It's here to stay until digital signing
becomes the requirement and you can say only accept emails from signed
sources and then ultimately signed sources you trust.  Some day maybe we
can charge legitimately spammers to read email.  

Till that day watch your list and if it suddenly dries up it may not be
your imagination.  Good to hear gmail has gotten better, wish I could
make a suggestion as to who to choose but the player switch ranks so
often that we don't bother trying to keep up anymore.

Kind regards,


-----Original Message-----
From: []
On Behalf Of MagerValp
Sent: Thursday, April 12, 2007 7:37 AM
Subject: Spam filters and mailing lists

As we're on the subject of spam and mailing lists, I'd like to say a
few things.

Please select a provider with good spam filtering servers. If you want
a good, free account with POP and webmail, I can recommend
It's out of beta, and invitation is no longer necessary.

Every time a spam filter misfires and decides to reject a mailing list
message, the bounce goes back to the mailing list maintainer (that'd
be me). One company in particular seems to have much crappier filters
than anyone else: (drumroll please :) They regularly block
legitimate mail, so if you're an aol user, I'd recommend switching to
another provider.

If your provider blocks using RBL, you're also losing a lot of
legitimate mail. RBLs that are used as part of a weighted filtering
system, such as spamassassin, work well, as any spaminess is
outweighed by the un-spaminess of the message content. RBLs that block
absolutely regularly bounce legitimate stuff (like CBM-hackers).

Spammers suck :/

    ___          .     .  .         .       . +  .         .      o   
  _|___|_   +   .  +     .     +         .  Per Olofsson, arkadspelare
    o-o    .      .     .   o         +
     -       +            +    .

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