NETGEAR WNR2000-100NAS user manual Msn, Common MTU Sizes

NETGEAR Wireless-N Router WNR2000 User Manual

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.

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.

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 5-1describes common MTU sizes and applications.

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.
5-16	Fine-Tuning Your Network

v1.0, June 2008