NETGEAR N300 ROUTER WNR2000 - Manual (Page 97)

NETGEAR Wireless-N 300 Router WNR2000 User Manual
Fine-Tuning Your Network 5-17
v1.3, July 2009
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 MTU unchanged unless one of these
situations occurs:
• You have problems connecting to your ISP, or other Internet service, and either the technical
support of the ISP or of NETGEAR recommends changing the MTU size. These might require
an MTU change:
– A secure Web site that will not open, or displays only part of a Web page
– Yahoo e-mail
– MSN
– 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.
If you suspect an MTU problem, a common solution is to change the MTU size to 1400. If you are
willing to experiment, you can gradually reduce the MTU size from the maximum value of 1500
until the problem goes away.
Table 5-1 describes common MTU sizes and applications.
Note: An incorrect MTU setting can cause Internet communication problems such as the
inability to access certain Web sites, frames within Web sites, secure login pages,
or FTP or POP servers.
Table 5-1. 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 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 e-mail 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.