[pptp-server] MRU/MTU on PPTP connection?

[Tim Small]

Hi,

I just wondered if anyone had any experience of performance-tuning pppd 
options with PoPToP (for use with MPPE in particular).  In particular, I 
should think that the MRU, and MTU values should probably be a bit less 
than the underlying TCP/IP connection MTU (e.g. 1500 for ethernet, 1400 
ish for ATM type ADSL), to allow for PPP packet overhead.  I also assume 
that you should specify "asyncmap 0".

The Windows98 SE box I'm using seems to default its MTU to 248 bytes 
(!).  I think this is the MS default for dial up networking 
connections.  If the PPTP is running over a dialup networking connection 
which hasn't been tweaked, I would guess that this should be lowered a 
bit (either that or put up to the 1500 byte full-whack)?

Any ideas anyone?

Cheers,

Tim.

p.s. Does anyone know of a ping (or other similar utility) for Linux 
which supports the manual-MTU-discovery of the Windows "ping -l xx -f"?