[122663] in North American Network Operators' Group
RE: Spamhaus and Barracuda Networks BRBL
daemon@ATHENA.MIT.EDU (John Souvestre)
Thu Feb 18 21:39:07 2010
From: "John Souvestre" <johns@sstar.com>
To: <nanog@nanog.org>
Date: Thu, 18 Feb 2010 20:38:26 -0600
In-Reply-To: <4B7DEE6F.3020408@opus1.com>
Errors-To: nanog-bounces+nanog.discuss=bloom-picayune.mit.edu@nanog.org
Hello Joel.
> I have some objective data based on our testing here. Over the past 18
> months, Barracuda's block rate is 81.9%, while Spamhaus' is 83.3%. For
> whatever measurement error you want to include, that says that they are
> roughly equivalent. Over the past 6 months, BRBL is actually getting
> better: their block rate is 87%, while Spamhaus is 82%.
>
> There is, of course, a catch. BRBL gets a higher rate, but at a
> substantially higher false positive (FP) rate. We normalize FPs per
> 10,000 messages our measurements. Over the last 18 months, BRBL was 4.1
> FP/10K messages; Spamhaus 0.2 FP/10K messages. Again, BRBL is getting
> better: over the past 6 months, BRBL went down to 1.6 FP/10K messages,
> while Spamhaus is about the same at 0.3 FP/10K messages.
Your numbers reflect what I see, too. One other thing to note is that the two
services don't catch exactly the same spam, so using both results in better
trapping than either one alone.
John
John Souvestre - New Orleans LA
