NETGEAR N750 DGND4000 User Manual page 51

N750 Wireless Dual Band Gigabit ADSL Modem Router DGND4000
The best MTU setting for NETGEAR equipment is often just the default value, and changing
the value might fix one problem but cause another. Leave the MTU unchanged unless one of
these situations occurs:
• You have 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
- Yahoo email
- MSN portal
- America Online's DSL service
• You use VPN and have severe performance problems.
• You used a program to optimize MTU for performance reasons, and now you have
connectivity or performance problems.
Note: An incorrect MTU setting can cause Internet communication
problems such as the inability to access certain websites, frames
within websites, secure login pages, or FTP or POP servers.
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.
Table 11. Common MTU sizes
MTU Application
1500 The largest Ethernet packet size and the default value. This is the typical setting for
non-PPPoE, non-VPN connections, and is the default value for NETGEAR wireless
modem routers, adapters, and switches.
1492 Used in PPPoE environments.
1472 Maximum size to use for pinging. (Larger packets are fragmented.)
1468 Used in some DHCP environments.
1460 Usable by AOL if you do not have large email attachments, for example.
1436 Used in PPTP environments or with VPN.
1400 Maximum size for AOL DSL.
576 Typical value to connect to dial up ISPs.
To change the MTU size:

1. Select ADVANCED > Setup > WAN Setup.
NETGEAR genie ADVANCED Home
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