Netopia 430 s Verweisanleitung

Security should be a high priority for anyone administering a network 
connected to the Internet. Using packet filters to control network 
communications can greatly improve your network’s security.

The Netopia ISDN Router’s packet filters are designed to provide 
security for the Internet connections made to and from your 
network. You can customize the router’s filter sets for a variety of 
packet filtering applications. Typically, you use filters to selectively 
admit or refuse TCP/IP connections from cer tain remote networks 
and specific hosts. You will also use filters to screen par ticular 
types of connections. This is commonly called firewalling your 
network.

Before creating filter sets, you should read the next few sections to 
learn more about how these power ful security tools work.

A filter is a rule that lets you specify what sor t of data can flow in 
and out of your network. A par ticular filter can either be an input 
filter—one that is used on data (packets) coming in to your network 
from the Internet—or an output filter—one that is used on data 
(packets) going out from your network to the Internet.

A filter set is a group of filters that work together to check incoming 
or outgoing data. A filter set can consist of a combination of input 
and output filters. 

A filter set acts like a team of customs inspectors. Each filter is an 
inspector through which incoming and outgoing packages must 
pass. The inspectors work as a team, but each inspects ever y 
package individually.