User's Manual

Wireless-N 300 Modem Router DGN2200 User Manual
6-2 Advanced Configuration
v1.0, November 2009
Figure 6-1
Table 6-1. WAN Settings
Setting Description
Disable SPI Firewall The SPI (Stateful Packet Inspection) Firewall protects your LAN against
Denial of Service attacks. This should only be disabled in special
circumstances
Default DMZ Server See “Setting Up a Default DMZ Server” on page 6-3.
Respond to a Ping on an Internet
WAN Port
If you want the wireless-N modem router to respond to a ping from the
Internet, select the Respond to Ping on Internet WAN Port check
box. This should be used only as a diagnostic tool, since it allows your
wireless-N modem router to be discovered. Do not select this check
box unless you have a specific reason to do so.
MTU Size The normal MTU (Maximum Transmit Unit) value for most Ethernet
networks is 1500 bytes, or 1492 bytes for PPPoE connections. For
some ISPs you might need to reduce the MTU. But this is rarely
required, and should not be done unless you are sure it is necessary for
your ISP connection.
NAT Filtering This option determines how the router deals with inbound traffic. The
Secured option provides a secured firewall to protect the PCs on LAN
from attacks from the Internet, but it may cause some Internet games,
point-to-point applications, or multimedia applications not to work. The
Open option, on the other hand, provides a much less secured firewall,
while it allows almost all Internet applications to work