Benchmarks: Setup two (old) i386 machines with two network interface cards each, connected with two crosswire Cat5 cables, 10 mbit/s unidirectional tester: generate TCP packets on ethernet level through first NIC, capture incoming ethernet frames on second NIC firewall: OpenBSD and GNU/Linux (equal hardware), IP forwarding enabled, packet filter enabled, no other services, no other network traffic, static arp table