fixing insecure email infrastructure (was: Re: [eweek article]

Markus Stumpf maex-lists-nanog at Space.Net
Mon Jan 24 19:54:48 UTC 2005

On Fri, Jan 14, 2005 at 10:05:05AM +1100, Mark Andrews wrote:
> >What is wrong with MTAMARK?
> 	As currently described it doesn't fit well with RFC 2317
> 	style delegations.  They would need to be converted to use
> 	DNAME instead of CNAME which requires all the delegating
> 	servers to be upgraded to support DNAME.

How many legit mailservers get their revDNS from RFC 2317 style
delegations? Marking hosts "MTA=no" is an addon for an explicit block.

I'd assume most ISPs cannot simply mark their revDNS with "MTA=no"
without changing contracts, but even adding "MTA=yes" would be of
a lot of help.

And it is really easy and doesn't have any negative side effects ;-)


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