Article ID: 283165 - View products that this article applies to.
This article was previously published under Q283165
This article describes how to change the Point-to-Point Protocol over Ethernet (PPPoE) Maximum Transfer Unit (MTU) size.
The default and maximum PPPoE MTU size is 1,480 bytes. With some Internet service providers (ISPs), you may have to reduce the MTU size of a PPPoE connection to a value between 1,400 and 1,480 (for example, to 1,454). Do not set an MTU size smaller than 1,400.
For additional information about the default MTU size, click the following article number to view the article in the Microsoft Knowledge Base:
314496For additional information about how to determine if you have to lower the MTU size of a PPPoE connection, click the following article number to view the article in the Microsoft Knowledge Base:
(http://support.microsoft.com/kb/314496/ )Default MTU size for different network topology
(http://support.microsoft.com/kb/159211/ )Diagnoses and treatment of black hole routers
Modify the MTU sizeImportant This section, method, or task contains steps that tell you how to modify the registry. However, serious problems might occur if you modify the registry incorrectly. Therefore, make sure that you follow these steps carefully. For added protection, back up the registry before you modify it. Then, you can restore the registry if a problem occurs. For more information about how to back up and restore the registry, click the following article number to view the article in the Microsoft Knowledge Base:
(http://support.microsoft.com/kb/322756/ )How to back up and restore the registry in Windows
To modify the PPPoE MTU size, create the following registry key:
Then add the following registry entries.
To do this:
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