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
•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.
An incorrect MTU setting can cause Internet communication problems. For example,
you might not be able to access certain websites, frames within websites, secure
login pages, or FTP or POP servers.
To change the MTU size:
1. Launch a web browser from a WiFi-enabled computer or mobile device that is connected to the network.
2. Type http://www.routerlogin.net.
A login window opens.
3. Enter the router user name and password.
The user name is admin. The default password is password. The user name and password are
The BASIC Home page displays.
4. Select ADVANCED > Setup > WAN Setup.
The WAN Setup page displays.
5. In the MTU Size field, enter a value from 64 to 1500.
6. Click the Apply button.
Your settings are saved.
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 applications.
Specify Your Internet Settings
Nighthawk X6S AC4000 Tri-Band WiFi Router