Does anyone know of a good MTA that can delivery emails quickly but efficently. The MTA must have the option for per domain throttling and be integratable with SPF, SenderID, and Domain Keys. I have looked into Hurricane MTA - It says it can send over 1,000,000 emails per hour. I understand that the server can play a role in this and bounces, and mx lookups. However, I am looking for a email solution that can process alot of emails. 1,000,000 emails per hour would be very nice, but must have domain throttling. I would perfer linux or windows.
Domain Throttling: amount of emails sent to that domain per hour, and or per connection.
Quad Core Xeon 5520
8 x 2.26GHz + hyper-threading CPU
2 x 250GB HDD
1 GigE (1000Mbit) port
Take a look at http://www.axigen.com/ - the ISP version specifically. It offers the features you require and more. Further, it comes in both MS and Linux versions.
Most enterprise class MTAs have the ability to handle 1 Million plus connections an hour - but not nessecarily 1 Million emails - as it would all depend on the actual message sizes (i.e. bandwidth + disk i/o).
Realistically, to handle the level of traffic you are looking at (and assuming that it is genuine email messages of varying sizes and not spam) you should really be looking at a small cluster of SMTP servers. Again the Axigen product handles such an environment.