Re: [Exim] SMTP authentication

Hello Ralph,

Ralph Ballier, 11.02.2004 (d.m.y):

> yes, this is exactly what I have set up between Linux client in my school,
> using a dial up connection (T-Online as access provider only) and my server/smarthost,
> named "schule.de", using a fixed IP number. Now authentication (username and password)
> is necessary for deliver mails from client to server.
> But I wonder, why my server can
> get mails from many other internet hosts whithout authentication. Note, I manager the
> server "schule.de" too.

Most frequently, SMTP authentication will be used to decide if the
client may use the server as a relay. Relaying means from the server's
point of view that it accepts an email although it is not directed to
one of the domains the server is configured to accept emails for.

For example:
The server is configured to treat the domain name ralph.schule.de as
local, so it will try to deliver mails for <username>@ralph.schule.de
to the local user <username>.
Relaying means accepting mails from authenticated users and to pass
them on to another server - either the "destination server" (derived
from a dns lookup for the destination domain's MX) or just a smarthost
that will do the "rest of the delivery".

If you want, just contact me in German...;-)

Yours,
Christian
--
[Zufaellig gewaehlte Signatur:]
Wie man sein Kind nicht nennen sollte:
Karl Auer