Question about high perfomance Linux firewall

["Javier Miguel Rodríguez" <javier.miguel@talika.eii.us.es>]

Hello

I have to built a FAST Linux firewall (12 gigabit ethernets), and I need 
your advice

My current setup is ( I can change things if needed)

Compaq Proliant DL380g4 (1 xeon 3.6 ghz, with hyperthreading, pci-x 
based, 1 gb ram)
2 broadcom gigabit ethernet cards (tg3 driver)
3 intel quad gigabit ethernet cards (e1000 driver)


I need to keep connection tracking, so nf-hipac is discarded. I will use 
almost no logging.
My ruleset will be rather short: 500-600 lines, with SNAT/DNAT in about 
5% of these rules. Only ipv4 will
be used in this firewall setup.

I expect substained rates of 300-400 megabits on EACH gigabit interface, 
with gigabit peaks. I also expect 40.000-50.000
concurrent connections (mainly http/smtp/dns traffic). I also expect 
500-600 megabits of NATed traffic (to & from  internet)


Which gigabit ethernet card is more suitable for high perfomance 
filtering? Any special advice
about linux distro/ kernel tuning?

Thank you for your support