[Mimedefang] Allowing only certain sender/recipient pairs

[Cormack, Ken]

> Does the person who asked you to do this understand how easy it is to
> forge the sender address?  It's a lot of work for almost no security...

The question came about because our sister campus (they own us) does this
using IronMail (Microsoft had advised them against doing this on their
Exchange servers).  Because management wants things to be more consistent
between campuses, the question was posed to me (where we use MIMEDefang).

> Note that if people connect directly to the MIMEDefang
> box with e-mail clients, they may get nasty error messages.

Fortunately, they don't.  Our MD gateways hand off to an inhouse relay that
then does domain-based routing to internal Exchange servers.

> CanIt-PRO can do it (in a rather cumbersome way -- it wasn't really
designed
> for that.)

I suspect no implimentation is anything other than cumbersome.  It's just a
question of which solution wants the sale bad enough to say "We can do
that... It's Easy!"  ::grimace::

Thanks all, for the replies (both on and off list).

Ken