When To Use The Firewall; Configuring A Filter Set; Figure 266 Menu 21: Filter And Firewall Setup - ZyXEL Communications ZyWALL 2Plus User Manual

32.2.2.1 When To Use The Firewall

1 To prevent DoS attacks and prevent hackers cracking your network.
2 A range of source and destination IP addresses as well as port numbers can be specified
within one firewall rule making the firewall a better choice when complex rules are
required.
3 To selectively block/allow inbound or outbound traffic between inside host/networks and
outside host/networks. Remember that filters cannot distinguish traffic originating from
an inside host or an outside host by IP address.
4 The firewall performs better than filtering if you need to check many rules.
5 Use the firewall if you need routine e-mail reports about your system or need to be alerted
when attacks occur.
6 The firewall can block specific URL traffic that might occur in the future. The URL can
be saved in an Access Control List (ACL) database.

32.3 Configuring a Filter Set

The ZyWALL includes filtering for NetBIOS over TCP/IP packets by default. To configure
another filter set, follow the procedure below.
1 Enter 21 in the main menu to open menu 21.

Figure 266 Menu 21: Filter and Firewall Setup

2 Enter 1 to bring up the following menu.
Chapter 32 Filter Configuration
Menu 21 - Filter and Firewall Setup
1. Filter Setup
2. Firewall Setup
Enter Menu Selection Number:
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