[Mimedefang] Sendmail,Spamassassin,Mimedefang Vs Hosted Solution

Jeff Rife mimedefang at nabs.net
Sat Jan 5 12:25:32 EST 2008

On 3 Jan 2008 at 15:14, Dj Helmes wrote:

> I have Sendmail,Spamassassin,Mimedefang & ClamAv running on 4 V440's.
> My supervisor is asking me to investigate hosted options such as
> (Postini, MXLogic) If I have to change anything, would like to
> implement CanIT.
> The supervisor's approach here is to give all of our end users the
> control to Whitelist, blacklist and manage their quarantined messages
> through a web based GUI.

I can't speak for all the options of CanIt, but most of the 
requirements you mention are listed in the documentation on the RP 
website.  So, you can use that as an argument...you'd give the boss 
what he wants the users to have but still have the flexibility that the 
MD/CanIt architecture provide.

> Any input from the list would be appreciated.
> I'm not sure how I feel about a hosted solution.  I do not like the
> Idea of sending the mail outside of our network
> Has anybody been through this type of thing before?

Not directly on the anti-spam switch, but I've definitely been through 
the change from on-site to a hosted solution, and unless you have a 
really big pipe per user, it quickly begins to suck based on the way 
real-world users work.

Imagine a user sending a 10MB attachment to 20 people in the company. 
Even internally, we tried to have rules that prevented this, but 
management required that it be allowed.  With complete internal e-mail, 
even if you end up delivering 20 copies of the attachment, all the 
traffic is over your LAN (100Mbps or 1Gbps), so although it was a silly 
way to get people to see a large attachment, it wasn't really a burden 
on the infrastructure (no scanning of internal to internal helps, of 

With an external hosting service, the attachment has to go out to the 
service and then back in to 20 machines.  Sure, the hosting service 
might only keep one copy on their server, but all your users will 
download it to their local client.  The more your people work together, 
the worse a hosting solution gets.  It does work better if the majority 
of your e-mail has either the sender or receiver not as part of your 

But still, the same thing happens if someone outside your organization 
sends an e-mail to a few people inside.  Your hosting service only 
deals with the bandwidth and storage of one copy incoming, but you have 
to have storage and bandwidth for every copy.

Jeff Rife | "A rabbit's foot?  You slaughtered an innocent 
          |  animal for some silly superstition?" 
          | "I didn't personally slaughter the rabbit.  I shot 
          |  a giant panda out of a tree, and he fell on it." 
          |         -- "Cybill" 

More information about the MIMEDefang mailing list