WINDOWS 2000 SERVER
CONFIGURE TCP/IP FILTERS
Firewalls are standard for every network, but they don't solve all
problems. While they do a great job of protecting a network of computers,
they do very little for each individual server. This is where a helpful,
yet rarely used, Windows 2000 feature can help you. TCP/IP filtering
lets you configure special IP filters that determine the type of network
traffic that reaches your computer.
specify which TCP or UDP ports and IP protocols to allow or not allow
into your server. While this is no substitute for a real firewall,
it will make your network a little more secure.
IP filters, follow these steps:
1. Open the Network And Dial-Up Connections folder, and right-click
the network interface that you want to configure IP filters for.
Properties, and click Advanced.
3. On the Options tab, select TCP/IP Filtering in the Optional Settings
Properties, and select the Enable TCP/IP Filtering check box.
5. For each filter type (TCP, UDP, IP), you can permit all and deny
only specified, or deny everything except the specified. (For instance,
if you want to allow only TCP Port 80 to your computer, click Permit
Only for all three filter types, and click Add for TCP Ports and specify
you're finished, click OK to close the dialog box.
Make sure you properly plan for TCP/IP filtering. Disabling everything
except ports you explicitly define creates stronger security because
you know exactly what's open. However, when configuring IP filters,
you must be very familiar with your network, or some applications
might stop working.