Manage the Internet Settings Manually
AC1600 WiFi VDSL/ADSL Modem Router Model D6400
10. To specify the interface ID for the IPv6 address of the modem router’s LAN interface, select
the Use This Interface ID check box, and enter the interface ID.
If you do not specify an ID here, the modem router generates one automatically from its
11. Click the Apply button.
Your settings are saved.
Manage the MTU Size
The maximum transmission unit (MTU) is the largest data packet a network device transmits.
When one network device communicates across the Internet with another, the data packets
travel through many devices along the way. If a device in the data path uses a lower MTU
setting than the other devices, the data packets must be split or “fragmented” to
accommodate the device with the smallest MTU.
The best MTU setting for NETGEAR equipment is often the default value. In some situations,
changing the value fixes one problem but causes another.
Leave the MTU unchanged unless one of these situations occurs:
•You experience problems connecting to your ISP or other Internet service, and the
technical support of either the ISP or NETGEAR recommends changing the MTU setting.
These web-based applications might require an MTU change:
-A secure website that does not open or displays only part of a web page
-America Online’s DSL service
•You use VPN and experience severe performance problems.
•You used a program to optimize MTU for performance reasons and now you are
experiencing connectivity or performance problems.
If you suspect an MTU problem, a common solution is to change the MTU to 1400. If you are
willing to experiment, you can gradually reduce the MTU from the maximum value of 1500
until the problem goes away. The following table describes common MTU sizes and