Re: educating rDNS violators

[SMiller () unimin com]

First, I am grateful for all of the answers received, so please do not
misinterpret the following.  I will let this stand for the group of
responses that might well be summarized by the expression "tough ti11y said
the kitty, but the milk's still sweet."  I don't know how much of those
respondents' critical business communications are conducted by email, but
for my employer it has become very high.  We also serve a customer base and
are in turn served by a vendor base that is technologically typically
trailing edge, and composed of concerns that are highly unlikely to
understand the need or method for publishing reverse DNS mappings.  Has it
been forgotten that this service (email) serves a utilitarian business
purpose?  That a vitally important contract, or bid, or quote opportunity
could be irrevocably lost as the result of denying email delivery from
legitimate business partners?  It isn't inconceivable that several hundred
thousand USD in revenue could swing on an undelivered email or five.  All
those here who would like to admit responsibility and disclaim "But I was
blocking spam", when your CEO asks IT how such a thing could possibly have
happened, raise your hands.  There is another old saw, "throwing the baby
out with the bath water".  To me, it seems that an inflexible
implementation of reverse dns validation of email at this time runs the
risk of accomplishing just that.  YMMV.

Scott


                                                                           
             James Kelly                                                   
             <jim@essistants.c                                             
             om>                                                        To 
                                       JGrimshaw () ASAP com                  
             08/24/2004 10:31                                           cc 
             PM                        security-basics () securityfocus com   
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                                       Re: educating rDNS violators        
                                                                           
                                                                           
                                                                           
                                                                           
                                                                           
                                                                           




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This may then force customers to switch providers to one who properly
sets up their service.

Jim

JGrimshaw () ASAP com wrote:
| With that in mind, with many customers using large ISPs for their public
| DNS service, a updating the bounce back message might not resolve
| anything, as the emailing site may not be in the authority to make the
| changes you have requested, and the large ISP may not have the
| wherewithall to implement such policies.
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