Question about NetGear DG814 DSL Modem Internet Gateway Router

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MTU what's MTU, and how do I tweak it?

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MTU, Partial Loss of Internet Connection, and Performance MTU (Maximum Transmission Unit) is the largest packet a network device transmits. The best MTU setting for NETGEAR equipment is often just the default value. MTU is sometimes presented as something that can be easily changed to improve performance, but in practice this may cause problems. Leave MTU unchanged unless one of these situations applies: 1. You have problems connecting to your ISP or other Internet service, and their technical support (or NETGEAR's) recommends changing MTU. For example, these services may require an MTU change: * Yahoo email * MSN * AOL's DSL service 2. You use VPN, and have severe performance problems. 3. You used a program to "optimize" MTU for performance reasons, and now you have connectivity or performance problems. * An easy solution to most problems is to change MTU to 1400. * If you are willing to experiment, gradually reduce MTU as described in "Details of MTU", below. How to Change a Computer's MTU Size Note: If you change MTU on one computer, it is likely you will want to change it on your other computers, switches, and routers, as well. Instructions for changing MTU on other NETGEAR devices is found in the Reference Manuals. The third party Dr. TCP software can be used to change the MTU setting. 1. Download it from this link, choosing the zip file or the exe file at the top of the page. 2. Run the utility. 3. In the Adapter Settings pull down, select the Ethernet driver and adapter used to connect with the network. 4. In the MTU box, type the MTU size you are trying. 5. Click in any other box, without changing the data there. 6. Click Save. 7. Click Exit. 8. Restart the computer. Details About MTU A packet sent to a device larger than its MTU is broken into pieces. Ideally, MTU would be set to the same ? large ? value on all your computers, routers and switches, as well as on all the parts of the Internet that you access. But you cannot control the MTU on the Internet, and in practice the optimum MTU size on your LAN is related to your hardware, software, wireless interference, etc. * Tweaking MTU size may work well in one situation, but cause performance and connection problems in others. * When network devices with different MTU settings communicate, packets are fragmented to accommodate the one with the smallest MTU. * Windows XP sets MTU automatically, that is, it optimizes computer MTU for you. This Microsoft article explains resolving lack of connection to a broadband ISP using Windows XP: * Once a network device fragments a packet, the data stays fragmented until arriving at the destination computer. Setting MTU size is a process of trial-and-error: start with the maximum value of 1500, then reduce the size until the problem goes away. Using one of these values is likely to solve problems caused by MTU size: * 1500. The largest Ethernet packet size; it is also the default value. This is the typical setting for non-PPPoE, non-VPN connections. The default value for NETGEAR routers, adapters and switches. * 1492. The size PPPoE prefers. * 1472. Maximum size to use for pinging. (Bigger packets are fragmented.) * 1468. The size DHCP prefers. * 1460. Usable by AOL if you don't have large email attachments, etc. * 1430. The size VPN and PPTP prefer. * 1400. Maximum size for AOL DSL. * 576. Typical value to connect to dial-up ISPs.

Posted on Feb 19, 2006

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How do i change my mtu settinggs

To change the MTU rate on your router follow the steps below:
Open your browser, enter the IP address of your router ( and click OK.
Enter your username (admin) and password (blank by default).
Click OK to enter the web configuration page for the device.
Click on Setup and then click Manual Configure.
To change the MTU enter the number in the MTU field and click Save Settings.
If changing the MTU does not resolve the problem, continue changing the MTU in increments of ten.

1500 is the default MTU for Dynamic (DHCP) Cable (p. 20 in user manual).
1492 is the default MTU for PPPoE (Point to Point Protocol over Ethernet) DSL (p. 22 in user manual).
Other MTU settings are listed in the manual, simply do a search for "MTU".

Note: AOL DSL+ users must use MTU of 1400.

To find the proper MTU Size, you'll have to do a special ping of the destination you're trying to go to. A destination could
be another computer, or a URL (p. 86 in user manual).

Here is the PDF link to the User Manual:

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TL WR740N can not open yahoo mail, youtube, facebook websites only is working fine any help please.

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1 Answer

I need to change the MTU settings

To change your MTU settings download a program called DrTCP (google for it) then change the MTU size of your Internet connection, try 1465 and keep dropping it until you get a figure that works...

You can also check out xbox support site for more information on MTU settings here

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Hi - do you know how to set the MTU settings on an Airlink RT210W ?

The MTU setting should already be set to 1500 this is the maximum possilbe for any TCP connection under Windows

You could use TCP Optimizer from speedguide which works by you selecting your actual download speed in kbps however the simplest solution is to use a reg tweak to optimize your ADSL connection.

This will set all the necessary values for you to get the most out of your tcpip.sys

NOTE: Be careful doing this can result in ADSL failure I suggest creating a drive image or a least a restore point first.

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How to change mtu settings to get x box live?

heres a good site that discusses adjusting the MTU(maximum transmission unit)
Usually in most cases MTU of 1500will work just fine, I suggest using DrTCP a free program available online to help you tweak your settings

Dont forget to rate the advice.

Aug 03, 2009 | Belkin Wireless G Plus MIMO (F5D9230-4)...

1 Answer

Mtu setting

In some cases, MTU is not necessary to adjust. Its always automatic and defaulted to 1500. The router model that you have doesn't have MTU settings. You can download the User's Manual HERE. You must do port forwarding and open the xbox live port so you can play xbox live. If it keeps on telling you about MTU, you must set static IP address on your xbox's settings and power cycle your devices.

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1 Answer

Xbox live MTU failure

The reason why you're getting an MTU error is because the MTU has already reached the maximum # of packets that are being sent. To resolve it.
Access the GUI of your Linksys Router and go to the MTU settings. Set it to 1500. The lower, the better

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Slow wireless speed!!

Try selecting other channels manually while configuring your wireless modem... it should not be in automatic... select either 1 or 11 then check...
try this and let me know
was i helpful?

Nov 21, 2008 | D-Link DGL-4500 Wireless Router

1 Answer

Needs to know more about MTU size changes

Changing the MTU size to any "small" value is a bad idea -- compare it to running to the corner store every time that you need to take anything (milk, ice-cube) out of your refrigerator -- the "time" to go back-and-forth to the store (or the Internet) will be excessive, and "slow" down your productivity.

Aug 04, 2008 | NetGear DG814 DSL Modem Internet Gateway...

2 Answers

I use Netgear DG834G with AOL9 Windows XP. Recently a number of sites are very slow to load or stop loading. I have been advised to change the MTU size to 1350. However when I try to do this the site does...


I am surprised that that you were advised to change MTU to 1350, it should normally be 1500 or at least 1450.

Have you done a Network repair? Right click on the networking icon in your system tray and click on Repair. Alternately, you can open a command prompt and type "ipconfig /fulshdns" and hit the enter key.

I wouldn't suspect your networking since some other sites presumably loads correctly and quickly enough. Perhaps what could be done is to tweak your networking connection both on the WAN side and the LAN side. Some utilities could do this for you instead of manually working on your registry. Some examples of tried good networking utilities are DRTCP.exe and TCPOptimizer.exe. You can do a Google for their download.

Additionally, WEP and WPA security have been known to slow down WiFi connections. Further using static IP addresses in your LAN would also be of help.

Hope this be of initial help/idea. Pls post back how things turned up or should you need additional information.

Good luck and kind regards.

Thank you for using FixYa.

Apr 01, 2008 | NetGear DG834G Router

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