MX dot was (Re: [ietf-dkim] TXT wildcards SSP issues

[Douglas Otis]

On Jun 11, 2007, at 5:43 AM, J.D. Falk wrote:

> On 2007-06-09 17:01, Hector Santos agreed with John Levine:
>
>>> "It's all spam" is about the simplest useful advice a (non)  
>>> sender can give.  In my case, which I don't think is unusual, I  
>>> get buckets of spam and blowback to subdomains that have never,  
>>> ever, sent a real message.  The domains are the names of  
>>> computers on my network, which were probably scraped out of  
>>> usenet or mail archive message IDs.  If receivers were to reject  
>>> or drop all mail purporting to be from those domains, it would be  
>>> uniformly better both for the receivers (less spam, cheap filter)  
>>> and for me (less blowback.)
>> +1
>
> +1

'Proof of use' as acceptance criteria should also eliminate much of  
this.  Deprecating and then obsoleting A record discovery would  
safely arrive at this goal.

Use of * MX "." would be something a root server will be unable to  
defending against.  If this were to become popular, these records may  
lead to a type of DDoS attack against the root servers.  This  
construct assumes millions of email applications will be modified to  
recognize "." as an invalid domain name.

-Doug