WRT-750N User Manual
37
MTU Size
The normal MTU (Maximum Transmit Unit) value for most Ethernet networks is 1500
Bytes, 1492 Bytes for PPPoE connections, or 1436 for PPTP connections. For some
ISPs you may 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.
Enable SIP ALG
Some SIP applications have their own way to work around the NAT firewall issue, and
the SIP ALG would conflict with those solutions. In most cases, you do not have to
disable the SIP ALG. However, if your SIP applications cannot work with the router,
you can disable the SIP ALG and try the applications again. Click on the check box to
disable SIP ALG.
Enable L2TP ALG
L2TP ALG for L2TP traffic can pass through the data. It is disabled by default, and if
you need to enable, check this box
Enable PPTP ALG
PPTP ALG can pass through the data for PPTP traffic. It is disabled by default, and if
you need to enable, check this box.
Enable IPSEC ALG
IPSEC ALG can pass through the data for such services. It is disabled by default, and if
you need to enable, check this box.
Enable IPv6 Pass-Through
IPv6 pass-through is disabled by default. If you have IPv6 capable devices in your
configuration and would like to use IPv6 instead IPv4, you can click on check box to
enable "IPv6 Pass-Through.
