CallerID & SPF

[John Coutts]

After reviewing both proposals in some detail, I have come to the conclusion
that Microsoft's CallerID proposal is inherantly flawed. Why? Because SPF
operates at the SMTP stage using the MAIL FROM: address. The flow of garbage
(alias Spam) is stopped before it is even transmitted. CallerID on the other
hand, operates on information that occurs after the DATA phase has begun. The
garbage has already been transmitted, and the spam engine will probably ignore
any error messages sent subsequently. This in turn encourages background
processing and leads to futile attempts to bounce the message.

Microsoft may have unlimited bandwidth and resources, but I don't.

J.A. Coutts

 

[Ace Fekay [MVP]]

After reviewing both proposals in some detail, I have come to the conclusion
that Microsoft's CallerID proposal is inherantly flawed. Why? Because SPF
operates at the SMTP stage using the MAIL FROM: address. The flow of garbage
(alias Spam) is stopped before it is even transmitted. CallerID on the other
hand, operates on information that occurs after the DATA phase has begun. The
garbage has already been transmitted, and the spam engine will probably ignore
any error messages sent subsequently. This in turn encourages background
processing and leads to futile attempts to bounce the message.

Microsoft may have unlimited bandwidth and resources, but I don't.

J.A. Coutts

Thanks for the viewpoint, but what does it have to do with DNS?

--
Regards,
Ace

Please direct all replies to the newsgroup so all can benefit.
This posting is provided "AS-IS" with no warranties and confers no
rights.

Ace Fekay, MCSE 2000, MCSE+I, MCSA, MCT, MVP
Microsoft Windows MVP - Active Directory

 

[John Coutts]

Thanks for the viewpoint, but what does it have to do with DNS?

********************* REPLY SEPARATER *********************
Both of these proposals deal extensively with DNS records. I would even go so
far as to say that it is all DNS, although the bulk of it is client side. One
of these, or perhaps a combination of these will eventually rise to the surface
and DNS administrators will have to deal with it, like it or not.

 

[Ace Fekay [MVP]]

********************* REPLY SEPARATER *********************
Both of these proposals deal extensively with DNS records. I would even go so
far as to say that it is all DNS, although the bulk of it is client side. One
of these, or perhaps a combination of these will eventually rise to the surface
and DNS administrators will have to deal with it, like it or not.

Hmm, maybe I have't been keeping up with my research and reading up on SPF.
So does that use SRVs to help in determining SPAM? I always assumed, once
the record has been resolved, then it attempts the SMTP session., but
apparently from what you're saying there's an extra step involved?

Maybe I'm not seeing it or just haven't read up enough on the subject. If
you don't mind, maybe there's others out here in the groups in the same
position I'm in and could use a little enlightenment on the subject.


--
Regards,
Ace

Please direct all replies to the newsgroup so all can benefit.
This posting is provided "AS-IS" with no warranties and confers no
rights.

Ace Fekay, MCSE 2000, MCSE+I, MCSA, MCT, MVP
Microsoft Windows MVP - Active Directory

 

[John Coutts]

Hmm, maybe I have't been keeping up with my research and reading up on SPF.
So does that use SRVs to help in determining SPAM? I always assumed, once
the record has been resolved, then it attempts the SMTP session., but
apparently from what you're saying there's an extra step involved?

Maybe I'm not seeing it or just haven't read up enough on the subject. If
you don't mind, maybe there's others out here in the groups in the same
position I'm in and could use a little enlightenment on the subject.

******************** REPLY SEPARATER ********************
Both proposals involve properly advertising not only the MX receiving servers,
but also the sending servers. There are many similarities, but also some
differences (one I have already mentioned).

SPF (Sender Policy Framework) is at http://spf.pobox.com/ and has an RFC draft
published.

 

[Ace Fekay [MVP]]

In

Both proposals involve properly advertising not only the MX receiving
servers, but also the sending servers. There are many similarities,
but also some differences (one I have already mentioned).

SPF (Sender Policy Framework) is at http://spf.pobox.com/ and has an
RFC draft published.

THanks for posting that link. I'l have to take a closer look at it.
--
Regards,
Ace

Please direct all replies to the newsgroup so all can benefit.
This posting is provided "AS-IS" with no warranties and confers no
rights.

Ace Fekay, MCSE 2000, MCSE+I, MCSA, MCT, MVP
Microsoft Windows MVP - Active Directory

 

[Jonathan de Boyne Pollard]

MF> Thanks for the viewpoint, but what does it have to do with DNS?

SPF's relationship to DNS is that it hijacks an existing, widely used and
long-standing, unstructured resource record type and imposes its own
semantics and structure upon it by fiat.

<URL:http://homepages.tesco.net./~J.deBo...f-is-harmful.html#HijackTXTResourceRecordType>