[pptp-server] question of performance ... ?

[John Van Ostrand]

We have seen good performance on LANs. I don't have the numbers but it is
much better than you describe. 

I don't think the baud rate in the config file has anything to do with the
actual transfer rate. In fact on the Win9x end Microsoft says the baud rate
reported on PPTP connections is an estimation based on the time it takes to
authenticate the tunnel.

We are having WAN performance problems though. I think it might be something
to do with the "windowing" that PPTP does. The TODO list indicates that
windowing needs to be improved. Bad windowing will cause significant
performance problems on links with high latency or packet loss.

Can anyone confirm that windowing is a problem? Is the development version
better at this?

Thanks,

John.

> -----Original Message-----
> From: Jean-Paul Chavant [mailto:chavant at geosys.fr]
> Sent: Friday, July 07, 2000 5:24 AM
> To: Pptp
> Subject: [pptp-server] question of performance ... ?
> 
> 
> Hello,
> 
> since i haved installed my PPTP VPN i have made test. And if 
> it possible i
> would like to know what you think about my tests ...
> 
> My server is a P3-600EB linux 2.2.14 box with PPTP 1.0.0 and 
> PPP 2.3.11
> patched with opensll patch.
> My clients are P133/64Mo , P200MMMX/128Mo and P2-300/128Mo 
> under Win95 and
> Dun1.3 (with 128 bits patch encryption).
> 
> All the boxes are on a switched LAN 10/100 Mb. server has a 
> 10/100 Mb NIC
> and client a 10 Mb NIC.
> 
> The first test is a ping with 56 bytes packets. the tunnel 
> connection works
> with a speed of 8,3 % of the clear connection ... :(
> 
> The second test is a FTP with a 10Mb file. On a clear 
> connection i have a
> rate of ~850 kbytes/s. On a PPTP connection i have a rate of 
> 150kbytes/s (17
> %) !!
> 
> I know that it's not the compression and the encryption 
> (except on the P133)
> which slow down the rate (i have made test with no encryption 
> / 40 bits
> encryption and 128 bits encryption and results were the same 
> ...). It's
> neither the connection cable = 10 Mb.
> 
> So i think it's probably :
> 
> 1. the protocol PPTP him self which is very slowly ...
> encapsulation/overhead/etc ? If it is that why the P2-300 is 
> so slow as the
> P200MMX ???
> 
> 2. the speed communication between pppd and pptpd or pppd and 
> the system
> (115200 in the /etc/ppp/options, but 115200 = 14.4 kbytes/s 
> and my rate is
> about 150 kbytes/s ...) ? (the first best idea i think ...)
> 
> 3. Win9x implementation of the PPTP protocol by Microsoft 
> which is very bad
> (possible) ? (the second best idea i think ...)
> 
> 
> Someone can help me or give me good explications please ?
> 
> thank you.
> 
> JPaul
> 
> _______________________________________________
> pptp-server maillist  -  pptp-server at lists.schulte.org
> http://lists.schulte.org/mailman/listinfo/pptp-server
> List services provided by www.schulteconsulting.com!
>