Watermarking and spoofed sender address

[Robert Lopez]

Kevin,

If we do use SPF could there be something in the way we use it that it does
not help?  We added it as part of our out soucing student email.

>From http://www.kitterman.com/getspf2.py as of Wed Mar 20 2013:
"
SPF record lookup and validation for: cnm.edu
SPF records are primarily published in DNS as TXT records.

The TXT records found for your domain are:
v=spf1 include:_spf.google.com mx ~all

SPF records should also be published in DNS as type SPF records.

Type SPF records found for the domain are:
v=spf1 include:_spf.google.com mx ~all

Checking to see if there is a valid SPF record.

Results - Record may be valid, but ambiguous: v=spf1 records of both type
TXT and SPF (type 99) present, but not identical

Found v=spf1 record for cnm.edu:
v=spf1 include:_spf.google.com mx ~all

evaluating...
SPF record passed validation test with pySPF (Python SPF library)!
"



On Wed, Mar 20, 2013 at 10:20 AM, Kevin Miller <Kevin_Miller at ci.juneau.ak.us
> wrote:

> For what you’re trying to do, SPF is a better option.  ****
>
> ** **
>
>  ...Kevin
> --
> Kevin Miller
> Network/email Administrator, CBJ MIS Dept.
> 155 South Seward Street
> Juneau, Alaska 99801
> Phone: (907) 586-0242, Fax: (907) 586-4500
> Registered Linux User No: 307357 ****
>
> *From:* mailscanner-bounces at lists.mailscanner.info [mailto:
> mailscanner-bounces at lists.mailscanner.info] *On Behalf Of *Robert Lopez
> *Sent:* Tuesday, March 19, 2013 3:58 PM
> *To:* MailScanner discussion
> *Subject:* Watermarking and spoofed sender address****
>
> ** **
>
> I understand watermarking is to defend against "joe job blowback". I think
> I understand that blowback problem is when email is sent, using for example
> my address, to many other domains and all the flack (blow back) comes back
> to me.****
>
> I am wondering if this watermarking is of any use in a type of SPAM we now
> frequently see. It is where email is sent to a list of addresses, all at
> our domain, and the from address is also the first address in the address
> list. Everyone else thinks the first person sent it. Our gateways send such
> email to Exchange and any communication back to the sender is entirely
> within Exchange and never comes back through the gateways again.
>
> In this kind of SPAM I have always considered it of no use. Am I wrong in
> my thinking?
> ****
>
>
> --
> Robert Lopez
> Unix Systems Administrator
> Central New Mexico Community College (CNM)
> 525 Buena Vista SE
> Albuquerque, New Mexico 87106 ****
>
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>
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>
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>
>


-- 
Robert Lopez
Unix Systems Administrator
Central New Mexico Community College (CNM)
525 Buena Vista SE
Albuquerque, New Mexico 87106
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