Joel M Snyder Joel.Snyder at Opus1.COM
Sun Feb 21 18:38:11 UTC 2010

On Sat, Feb 20, 2010 at 7:25 PM, Jon Lewis <jlewis at> wrote:
 > > IMO, the original question in this thread was on-topic, but 
unfortunately it
 > > got very little discussion

 >I like spamhaus, they run a quality list, but they want between $1900
 >and $19000 per year for their rsync service and you have to tell them
 >how many email customers you're supporting in order to pay less than
 >the max. That would be an acceptable price to pay for antispam efforts
 >overall, but I couldn't afford to pay that for *each* of the dozens of
 >services spamassassin consults while analyzing a message.

I wonder if the pricing you've got is old.  I just did a test of a 
product and got pricing of $420/year for 600 users when I queried them. 
    Essentially, less than $1/user/user.

I understand that you are querying dozens of services with SpamAssassin, 
but I can guarantee you're not getting value for all that traffic you're 
generating.  In our research, we've found very little value to stacking 
reputation services.  And even stacking content filters can cause more 
problems than it solves if you don't pick them VERY carefully.

Just as an example, last month one of the content filters (think of it 
as an anti-spam product like SpamAssassin, but NOT including any 
reputation component) I tested ran with approximately an 81% catch rate. 
  Add in a single reputation filter, and that jumps up to 92.36%.  Add 
in three reputation filters, and the new rate is 92.99%.  Add in every 
single reputation filter I'm testing (that was 32 of them last month) 
and the rate barely jumped to 93.02%---but the false positive count 
jumped by 112 messages per 10,000 (because APEWS was somehow having a 
lousy month).

In general, the more reputation services you include, the more likely it 
is you're going to have false positives.


Joel M Snyder, 1404 East Lind Road, Tucson, AZ, 85719
Senior Partner, Opus One       Phone: +1 520 324 0494
jms at Opus1.COM      

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