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RE: email address "spoofed"
From: "Aditya, ALD [Aditya Lalit Deshmukh]" <aditya.deshmukh () online gateway technolabs net>
Date: Wed, 10 Mar 2004 15:32:14 +0530

Note that by now many SMTP servers reject mail unless they get *some*
answer on the reverse lookup; few spend much effort detecting spoofed 
HELO names, which often are made-up IP addresses or the name of the
receiving server (in hopes of bypassing any relay filters in place).


this is the case of the server on which the openssl mailing list run, the server will try to reverse resolve the domain 
if it does not get it responce it simply reject all the mail. this is good at cutting spam. but there is a problem who 
get his address assigned on a dhcp lease that expires every 8 hours, of course all the forward dns records are updates 
as soon as this occurs but the reverse dns my isp refuses to set them up. so i have to use some very convuluted method 
to send mail to openssl mailing list.

i think, the server should try to forward resolve the dns name that it recieves in helo and if it does not match then 
reject, because setting up the reverse is in the hands of whoever controls the dns server. many times this is not 
someone who would setup and update the reverse records 

-aditya


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