cpu needed to NAT 45mbs

Thu Nov 8 20:38:09 UTC 2007

Darden, Patrick S. wrote:
> 
> From my experience, a fast P4 linux box with 2 good NICs can NAT
> 45Mbps easily.  I am NAT/PATing >4,000 desktops with extensive access
> control lists and no speed issues.  This isn't over a 45Mb T3--this
> is over 100 Mb Ethernet.

NAT processing requirement thresholds are all about *flows* per second, not *bytes* per second.  Once you have a cached flow, it's trivial.  The overhead of statefully tracking flows, setup, teardown, timeouts, housecleaning, etc., are the limiting factors.

If you want to stress-test it, you should benchmark it with SQL Slammer :-)

Jeff