I have two machines both connected via ADSL (512 down and 256 up) to the
Internet. On side is running an openvpn server (debian) and the other is
a client (Windows XP).
Whilst on the client XP end pulling a few MB across the VPN, I was
looking at the Network Utilization tool that Win XP has (ctrl,shift &
esc) and was comparing the usage of the VPN adapter to the ADSL modem
The VPN adapter was sat right on about 2.5% usage and Windows thinks it
is 10Mbps. The ADSL adapter was pretty consistently on 13-15% and
windows thinks its maximum is 576kbps.
2.5% of 10Mbps is 256kbps and this looked good because the uplink on the
server end is 256, but 14% of 576kbps is about 80kbps.
It therefore seemed to me that the VPN adapter was putting stuff through
at 256kbps. VPN was compressing it and transmitting down the real ADSL
adapter at around 80kbps. Am I right?
Why then, for example, did VPN not use 90-100% of the available ADSL
line and get a throughput over the VPN adapter of three times 256? Is
there anyway to tell VPN to use all of the available link? Is it, do you
think, that XP cant count the usage properly?
Many thanks for your thoughts....