MTU of the Internet?

Matthew Petach mpetach at netflight.com
Thu Feb 5 09:16:50 UTC 1998


> 
> Several people have noted to the Microsoft Support and Product groups that
> they want the Windows 95 PPP MTU to be set to 576 (down from 1500).  this
> change is in Windows 98.

Wrong direction.
 
> The reason for this change cited by many customers is that many ISPs have
> 576 MTUs set "inside" their networks and packets get fragmented.

Nope.
 
> How prevelant is this fragmentation and how prevelant is this MTU in ISPs?

It's not.  Quite frankly, I like the 9127 used by Alteon switches
and NICs within our network.  
 
> Why do ISPs set their MTUs to 576 instead of ~1500 or even ~4K?

We don't.  In fact, we like the MTUs as high as possible, hence
the choice of Alteon, with jumbo frames.
 
> thanks in advance for your responses,
> peter

You're welcome!  Please take this feedback, and adjust Win2000
accordingly...  :-)

Thanks!

Matt




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