3 ms·

> I suppose it ensures that if the recipient isn’t using TLS with SMTP then it’s not sent unencrypted over the wire, … I discovered setting up an old IP camera

> I suppose it ensures that if the recipient isn’t using TLS with SMTP then it’s not sent unencrypted over the wire, … I discovered setting up an old IP camera recently that it’s now very hard to send an unencrypted email via SMTP. Nearly all servers refuse to relay unauthenticated emails (no username and password), and only permit authentication if the connection is SSL or promoted to SSL via STARTTLS (ie encrypted). (I mention it because the camera wouldn’t cooperate or tell me what the problem was - ended up having to learn Wireshark and read the relevant RFCs re Authenticated SMTP).

Karrot_Kream 5y ago
I went through this process just the other day, setting up Postfix on a Zerotier network. Postfix lets you specify a "mynetworks" config option that lets you allow certain IP ranges. I added the Zerotier IPv6 assigned ranges to this list, disabled any form of TLS on the smtpd end, and was able to effectively turn off TLS. It was more annoying than I thought it would be but it makes sense given how few real world deployments lack TLS these days.