48 
II. 
Parameter explanation 
Follow these instructions to configure global firewall settings. 
Configure any of the following settings that display in the 
Firewall Global Configuration table:  
z 
Blacklist Status: If you want the device to maintain and 
use a black list, click 
Enable
. Click 
Disable
 if you do not 
want to maintain a list. 
z 
Blacklist Period(min): Specifying the number of minutes 
that a computer's IP address will remain on the black list 
(i.e., all traffic originating from that computer will be 
blocked from passing through any interface on the MT800). 
For more information, see Managing the Black List below.  
z 
Attack Protection: Click the Enable  radio button to use 
the built-in firewall protections that prevent the following 
common types of attacks:  
z 
IP Spoofing: Sending packets over the WAN 
interface using an internal LAN IP address as the 
source address. 
z 
Tear Drop: Sending packets that contain overlapping 
fragments. 
z 
Smurf and Fraggle: Sending packets that use the 
WAN or LAN IP broadcast address as the source 
address.  
z 
Land Attack: Sending packets that use the same 
address as the source and destination address. 
z 
Ping of Death: Illegal IP packet length. 
z 
DoS Protection: Click the Enable radio button to use the 
following denial of service protections: SYN DoS, ICMP 
DoS, Per-host DoS protection.