[Info-vax] Decuserve.org - Anyone know why it's down?

[Bill Gunshannon]

In article <m8h5r0$uvo$1 at dont-email.me>,
	Stephen Hoffman <seaohveh at hoffmanlabs.invalid> writes:
> On 2015-01-06 17:04:15 +0000, JF Mezei said:
> 
>> On 15-01-06 10:12, Bill Gunshannon wrote:
>> 
>>> That is what we are talking about.  The A and PTR must match or the
>>> system is mis-configured or spoofing and mail should not be accepted.
>> 
>> Nop.  Multiple A records may point to a single PTR which means the one
>> PTR for an IP address may not necessarily point to the host name being
>> used to send email. Consider multi-homed email server that handles many
>> domains.
> 
> A multi-homed email server that provides email services for many 
> domains has one A record and one PTR record, and zero or more MX 
> records.  That mail server will initiate its outbound SMTP connections 
> using its own host name, and which has a matching PTR.   If PTR for 
> that address does not match, then the mail server can be 
> (mis?)classified as a spam engine.
 
Just one small nit, which I think is causing a lot of this confussion.
This is not about anti-spam. It is effective to some extent because of
the methods used by many spammers, but the actual problem this addresses
is hostname spoofing which has more uses than just sending out spam.

Does no one here even remember the duels between "kremvax" and "nsavax"?
A humorous use of spoofing, but spoofing all the same (and yes, I know it
was long before there was an Internet and SMTP.)

bill 


-- 
Bill Gunshannon          |  de-moc-ra-cy (di mok' ra see) n.  Three wolves
billg999 at cs.scranton.edu |  and a sheep voting on what's for dinner.
University of Scranton   |
Scranton, Pennsylvania   |         #include <std.disclaimer.h>