ORBS (Re: Scanning)

Roeland Meyer rmeyer at mhsc.com
Sun May 27 18:10:08 UTC 2001

> From: Derek Balling [mailto:dredd at megacity.org]
> Sent: Sunday, May 27, 2001 10:49 AM
> At 9:11 AM -0700 5/27/01, Roeland Meyer wrote:
> >A system that tests positive for ORBS , yet is using MAPS, 
> will not be used
> >as a spam relay. Yet, ORBS will list such a system.
> I'm not sure I understand this logic:
> 1.) They test positive for orbs... so they ARE an open relay
> 2.) That system is using MAPS, which means that there is some subset 
> of systems the open relay itself rejects mail from

I somehow missed your logic here. A MAPS blocked system is, by definition
NOT an open-relay, since it IS MAPS-blocked. Yet, ORBS will list it as an
open-relay. I agree, there is a disconnect here. Your second premis
invalidates the first. This may be a semantic issue, please examine and

A MAPS-blocked system may show as an open-relay to another system not listed
in MAPS. However, it will show as closed to a system that is listed in MAPS.
It all depends on the source of the test. AHA! Maybe ORBS should be listed
in MAPS? That will certainly resolve this problem and ORBS will no longer
show false positives.

> Somehow that means that non-MAPS-listed sources (of which there are 
> many) are somehow magically restricted from relaying through the open 
> relay?

Since your first sylogy didn't parse, this one didn't either.

I might point out that, since MAPS has been running for a few years, most if
not all, the spammer sources are now listed.

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