Noel Jones:
> On 8/29/2013 3:43 PM, Glenn English wrote:
> >
> > On Aug 29, 2013, at 2:18 PM, LuKreme wrote:
> >
> >> $ grep 587 /etc/services
> >> submission 587/tcp
> >> submission 587/udp
> >
> > That's what mine says too. Does Postfix accept UDP submissions?
> >
> > I looked at RFC6409 (the newest I could find on 587), and all it said was
> > "port 587" -- the protocol isn't mentioned.
> >
>
> It's standard SMTP over tcp, typically with STARTTLS and AUTH. I
> imagine the udp entry is a historical artifact.
Plaintext SMTP over UDP would require that the MTA invents major
parts of TCP, including the parts that deal with packet loss,
out-of-order arrival, and flow control.
DTLS and DCCP, on the other hand, already deal with this, so it
might be practical.
Wietse
