User's Manual

Firewall Configuration
91
5
IP Filtering
This page is used to filter the IP addresses of clients attempting to access the
Internet based on the source or destination IP address and TCP/UDP port of each
packet. Address filtering allows the Gateway to permit or deny specified packets
passing through to the Internet.
Click FIREWALL, IP Filtering. Mark the check box to enable IP address filtering. Set
the addresses to be filtered, the TCP/UDP port, specify whether the matching
packets are to be passed on or dropped, and then click ADD to enter each address
in the table. Once all of the address entries have been specified, click Apply.
Figure 5-44 IP Filtering
Field Attributes
•Policy – Specifies to deny packets matching an entry.
• Enable IP Filter – Enables filtering of all packets in the IP Filtering List.
•Protocol – Specifies a port typem TCP, UDP, ICMP or all.
• Source/Destination – Specifies whether the address is contained in the packet’s
source or destination field.
• Mask – The network prefix which indicates the number of significant bits used to
identify the network portion of the address.
• Port – Specifies the TCP/UDP port number. (Range: 0-65535)