On Thu, 2011-01-06 at 00:27 +0100, mouss wrote:
> Le 05/01/2011 02:15, Karsten Bräckelmann a écrit :
> > On Tue, 2011-01-04 at 00:58 +0100, mouss wrote:
> > > Recipient unknown................: 5318 ( 73.85 %)
> > > DNSBL zen.spamhaus.org...........: 816 ( 11.33 %)
> >
> > This alone tells some facts about these stats. For one, they are
> > gathered from all SMTP delivery attempts. Usually, on this list, stats
> > for BL performance are relative to mail that otherwise would have been
> > accepted without SA. Which in every case but the most pathetic does not
> > include unknown recipient rejections at all.
>
> My understanding was that OP asked about smtp time rejections.
> obviously, this won't check received headers, nor junk from yahoo/gmail/...
That was my understanding, too. My point though was, that given a sanely
configured server without SMTP rejections based on BLs, the expected
difference will be nothing like the numbers above.
Current spam stats for such a server usually will be based on the SA
results, totally ignoring unknown recipient rejections, which happen way
earlier. In that case, ZEN will make a difference of rejecting 80% or
more -- based on the number of mails previously processed by SA, after
the most basic SMTP rejections. Not a mere 11%...
> > > as you can see, all DNSBLs but spamhaus are more or less useless.
> >
> > While ZEN in stats indeed tends to have the best hitrate and a
> > negligible FP rate, that sentence is incorrect as written.
>
> sorry if I wasn't clear: I mean at smtp time.
>
> > It definitely
> > depends on the order -- and whether or not you are able to use ZEN
> > (below the free usage limit or a paying rsync client).
>
> true.
Oh, it was obvious you meant at SMTP time, not discussing their weight
in a scoring system. ;) My point only was the order, which ultimately
affects the stats and "useless vs worthwhile".
> > BLs low in your order most likely will perform better, if used before
> > ZEN, and ZEN will perform worse if used after other BLs.
--
char *t="\10pse\0r\0dtu...@ghno\x4e\xc8\x79\xf4\xab\x51\x8a\x10\xf4\xf4\xc4";
main(){ char h,m=h=*t++,*x=t+2*h,c,i,l=*x,s=0; for (i=0;i<l;i++){ i%8? c<<=1:
(c=*++x); c&128 && (s+=h); if (!(h>>=1)||!t[s+h]){ putchar(t[s]);h=m;s=0; }}}
