ORBS (Re: Scanning)

Roeland Meyer rmeyer at mhsc.com
Sun May 27 18:30:28 UTC 2001

> From: Derek Balling [mailto:dredd at megacity.org]
> Sent: Sunday, May 27, 2001 11:20 AM
> At 11:10 AM -0700 5/27/01, Roeland Meyer wrote:
> >  > 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
> >clarify.
> I think this is all a phrasology thing.

I'm sorry. I hate hare-splitting too.

> Assuming "a MAPS-blocked system" means a system that is 
> listed/blocked by MAPS as a spam source.
>     Then your statement makes no sense because in all 
> likelihood, that 
> host IS an open relay.

My bad. What I meant was a MAPS-blocked system as a subcriber to MAPS. Not a
MAPS-known spam source.

> Assuming "a MAPS-blocked system" means a system that is partaking of 
> the MAPS lists to block inbound mail to it
>     Then your statement further makes no sense, because any 
> non-MAPS-listed host could (in theory) send mail to/through that 
> system. If the system using MAPS is an open relay, then 
> non-MAPS-listed hosts could quite happily/easily pump mail through 
> that system regardless of whether or not it is using MAPS.

Not true, I'm assuming that MAPS isn't the only anti-spam measures being

> >I might point out that, since MAPS has been running for a 
> few years, most if
> >not all, the spammer sources are now listed.
> I think my personal evidence (that about 90-95% of my spam that is 
> blocked is NOT from MAPS sources) does not seem to bear that out.

You bear out my assumptions that other methods, besides MAPS and ORBS, are
being deployed as well. Feeding such data into MAPS would improve MAPS

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