Re: Proposal for new SMTP error code

["Robert Sargent 615-481-2168" <sargent@xxxxxxxxxxxxxx>]

Alain, John, Francis:

I agree the additional error code functionality would in some
cases be helpful, but I'd like to see something done up the
stack a bit, not just on port 25.  I'd like to see something
that addresses every port that a particular machine doesn't
use or is not publically available.  A good many machines now 
simply REFUSE CONNECT, but don't say why.

It would be nice to have a machine reply to a request to connect to
port "Y" as one of:

1. Accept the connection.

2. Refuse connection - I never accept connections to port "Y".

3. Refuse connection - Congestion, try again later.

4. Refuse connection - Never to YOU.

The client can then react accordingly:

If #1 (above) do normal stuff.
If #2 the client can take other steps, in the case of SMTP check
for [other] MX records (either lower precedence or domain defaults).
If #3, the client can queue for later or react as if #2.
If #4, the client can take other steps or give up (and maybe notify
admins of the rejection).

Again, I agree something should be done, but I think more ports
than port just 25 have similar problems.  I certainly have not thought
this through for every single port, but am interested in your 
ideas/thoughts in this broader approach.

Robert Sargent