Submission/SMTP proxy server

[Stephan Bosch]

Op 1/12/2018 om 8:18 PM schreef Daniel Miller:
> Sorry if this seems elementary - but a question on
> implementation/usage/purpose of this.  My understanding is at this
> time the SMTP proxy server is only that - it does not implement any
> further functionality.  So its availability now is purely for testing
> purposes.  Is that accurate?

No. This is a proxy that adds functionality that is normally either
rather difficult to achieve or not implemented for common SMTP software
(e.g. BURL).

> I secondly assume that this intended for trusted clients only - so
> this is not intended for processing email submitted via port 25.

It is a submission service. Port 25 is for mail transport. Read
https://tools.ietf.org/html/rfc6409 for more details about the
difference between the two.

> And thirdly - if a separate firewall/anti-spam/virus/authentication
> service is run outside of the MTA (like ASSP) then the Dovecot proxy
> should be inserted between that and the final MTA?

Dovecot submission is meant to be talking to the client directly, so it
would be in front of it all. So, I'd expect Dovecot<->ASSP<->MTA.
Dovecot would in that case take care of the authentication.

Regards,

Stephan.