[[NBK] G.I. Jerk]

Here's a cheap and easy fix.

Buy a 10Mbit NIC for about $15. Add it to your server. Enable internet connection sharing (also known as NAT -network address translation) and put your gaming machine BEHIND (figuratively) the server. The server will act as a "proxy" for your other machine sharing its net connection while ALSO hiding it from the outside work. This is free security making it fairly unhackable.

Don't forget to set net_ip in your server.cfg file too.