Problems sending mail to yahoo?

Peter Dambier peter at
Sun Apr 13 08:07:37 UTC 2008

Roger Marquis wrote:

> Sounds like the party line inside Yahoo, but there are plenty of ISPs that
> do a really good job of combating spam.  They do it with standard tools
> like RBLs, Spamassassin, OCR, ClamAV and without ineffective diversions
> like SPF or DKIM.

Seen from inside, it is not spamfilters but it is the routing table.
I have seen spam dropping by 98% when zerorouting some networks.

Nobody complained about false positives :)

But this is another story for the big ones. They might have customers.

> The problem is that it is an art, not well documented (without reading
> 5 or 6 sendmail/postfix and anti-spam mailing lists for a several years),
> is not taught in school (unlike systems and network administration), and
> rarely gets measured with decent metrics.

That is true. Plus the rules are constantly changeing.

> Not that spam really has much to do with network operations, well, except
> perhaps for those pesky Netcool/Openview/Nagios alerts...

At the edge it does. It can bring your VoIP down and video on demand.

I know from campus networks who improved p2p service when zerorouting
networks known for sending spam.


Peter and Karin Dambier
Cesidian Root - Radice Cesidiana
Rimbacher Strasse 16
D-69509 Moerlenbach-Bonsweiher
+49(6209)795-816 (Telekom)
+49(6252)750-308 (VoIP:
mail: peter at

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