[Discuss] Running a mail server, or not

[epp at linuxmail.org (epp at linuxmail.org)]

On 06/27/2018 07:14 PM, Richard Pieri wrote:
> On 6/27/2018 7:05 PM, epp at linuxmail.org wrote:
>> I've noticed when e-mail comes into a Comcast address, the sending mail
>> server (Yahoo/AOL (when it works), Gmail, mail.com, GMX, etc.), the
>> receiving Comcast server receives it with SMTP. But when Comcast sends
>> an e-mail out to one of these services, it sends with ESMTPS (secure).
>> Why secure connections one-way and not both directions?
> My WAG? Comcast are logging all connections as SMTP regardless of
> encryption.
>
>> I have also noticed when sending through Yahoo/AOL (again, when it
>> works), even though the Thunderbird settings are set to use SSL or
>> STARTTLS, the receiving Yahoo server always receives it with SMTP.
>> Server mis-configuration there?
> If Thunderbird is configured to use SSL/TLS for a given account or
> outgoing mail server then the connections are always encrypted. Always.
> STARTTLS is opportunistic so connections might or might not be encrypted.



Received: from sonic301-4.consmr.mail.bf2.yahoo.com ([74.6.129.43]) by 
resimta-ch2-15v.sys.comcast.net with SMTP

Received: from mail-qt0-x233.google.com ([IPv6:2607:f8b0:400d:c0d::233]) 
by resimta-po-04v.sys.comcast.net with SMTP

Received: from (mobile IP address removed) by 
resomta-po-16v.sys.comcast.net with ESMTPSA

(This last one, was Comcast-to-Comcast, SSL both ways in the settings.)

So yes, it appears that Comcast is logging all inbound connections 
coming from outside as SMTP.