Jukka Marin writes:
> On Mon, Sep 22, 1997 at 10:38:29AM -0600, Alex Barclay wrote:
> 
> > 1) Micro$haft are following one of the RFC's for enhancing TCP throughput
> > by avoiding fragmentation (hence the DF flag that you see)

No they are not. They just don't do fragmentation properly. True path
MTU discovery would require that they lower their packet sizes
dynamically, which they Do Not Do. It would also require that they
ACCEPT fragmented packets, which they Do Not Do.

> Then NetBSD must have this problem.  I use NetBSD 1.2 machines as routers
> and my win95 system can't talk to the net properly because my PPP link has
> MTU of 576 bytes (or so, much less than 1500 bytes anyway).  If I change
> MTU to 1500, everything works ok.

This is a problem in Microsoft's stupid TCP stack. It is not your
fault at all.

Perry