Transparent email proxy

[Jeffrey Goldberg]

On Jul 13, 2007, at 2:30 AM, Olivier Nicole wrote:

> As an ISP, or the person in charge of a large organisation, have you
> ever set-up a transparent email redirection: all outgoing email would
> be proceeded to an outgoing server in order to check for virus, spam,
> whatever.

I've done this non-transparently many times.  At the perimeter  
firewalls the only traffic to port 25 which was allowed was from our  
official outgoing mail servers.

With the firewall, it is easy to make the use of the outgoing mail  
hub compulsory.  Is there some reason beyond that that you want to do  
things transparently?

-j

-- 
Jeffrey Goldberg                        http://www.goldmark.org/jeff/