Re: [ietf-smtp] Possible cont4ibution to moving forward with RFC5321bis SMTP

[Dave Crocker <[e-mail]>]

On 1/2/2020 11:34 AM, Keith Moore wrote:
> On 1/2/20 2:08 PM, Dave Crocker wrote:
>> You meant something like: "the sequence of hops starting with the MSA 
>> and ending with the receiving MTA at the destination site".
> 
> Actually I was trying to focus on the single hop between the last MTA of 
> an originating domain and the first MTA of the destination domain.

then referencing MSA continues to confuse me.

Might be worth looking at RFC 5598, Sections 2.2 and 2.3.


>> I'd misunderstood and thought you meant that the MSA interacted 
>> directly with the receiving MTA. 
> 
> That is possible (and in some cases desirable IMO).  

Not really, though this highlights the difference between network 
architecture and network implementation.  The former is an abstraction, 
with lots of possible implementation configurations.

If the box doing the MSA also talks to the receiving MTA, then that 
first box is also an MTA.


d/


-- 
Dave Crocker
Brandenburg InternetWorking
bbiw.net