The End-To-End Internet (was Re: Blocking MX query)

Michael Thomas mike at
Wed Sep 5 20:01:59 UTC 2012

On 09/05/2012 12:50 PM, Daniel Taylor wrote:
> On 09/05/2012 10:19 AM, Michael Thomas wrote:
>> On 09/05/2012 05:56 AM, Daniel Taylor wrote:
>>> On 09/04/2012 03:52 PM, Michael Thomas wrote:
>>>> On 09/04/2012 09:34 AM, Daniel Taylor wrote:
>>>>> If you are sending direct SMTP on behalf of your domain from essentially random locations, how are we supposed to pick you out from spammers that do the same?
>>>> Use DKIM.
>>> You say that like it's a lower bar than setting up a fixed SMTP server and using that.
>> I say it like it addresses your concern.
> Well, if you've got proper forward and reverse DNS, and your portable SMTP server identifies itself properly, and you are using networks that don't filter outbound port 25, AND you have DKIM configured correctly and aren't using it for a situation for which it is inappropriate, then you'll get the same results with a portable SMTP server that you would sending through a properly configured static server.
> So, no, "use DKIM" does not address the delivery difficulties inherent to using a portable SMTP server.
My how the goalposts are moving. DKIM solves the problem of producing
a stable identifier for a mail stream which is what your originally positioned
goalposts was asking for. It also makes reverse dns lookups even more
useless than they already are.


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