Hello lately I do not hear a lot about this draft
I was thinking about the draft and I think we need a chapter between section
3 and 4 about how mail looks at the host level
(very) short first layout
section 4 Hosts level
Email flows over the internet from one host to another.
at this level we just give that hosts names.
Sometimes hosts are missing or merged together but in principle this are
building blocks of the mailsystem.
this level is especially for introduction the mailsystem to beginners in
email and email architecture (like me)
At the host level the mail-architecture looks like:
Hosts : Agents
level : level
:
USER :
| :
V :
/--------------\ :
| sending | :
| mail | : MUA
| client | :
\--------------/ :
| :
push :
V :
/--------------\ :
| sending | : MSA
| mail | ===:============\\
| server | : sMTA ||
\--------------/ : ||
| : ||
push : ||
V : ||
/--------------\ : ||
| intermediate | : || mail
| mail | : (I)MTA || handling
| server | : || system
\--------------/ : || MHS
| : ||
: : ||
: : ||
V : ||
/--------------\ : ||
| intermediate | : ||
| mail | : (I)MTA ||
| server | : ||
\--------------/ : ||
| : ||
push : ||
V : ||
/--------------\ : ||
| receiving | : rMTA ||
| mail | ====:=====MDA====//
| server | : sMS
\--------------/ :
| :
pull :
V :
/--------------\ :
| receiving | : MRA
| mail | : lMS
| client | : MUA
\--------------/ :
|
V
USER
In this diagram I also name the agents that reside in each host.
And gave an indication where the boundaries of the MHS are.