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

[Jean-Paul Chavant]

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