Virtual Adapter TAP-Win32 Provider V9

aleksander_2005

Hello.
Who know how up speed on virtual adapter TAP-Win32 Provider V9 my system say this adapter have 10mbit/s
I set 2 PC and create tunnel , and see my speed on tunnel 2,5 mb per seconds ~ 10mbit/s
It's sad ...
How up speed on device ?

maybe i can use lan adapter ? but how
Thanks

janjust

the 10 Mbps that the tap-win32 adapter reports is a bogus number; actual speeds depend on your setup; I can achieve 80 Mbps going from a Win7 64bit client to a Linux 64bit server.

aleksander_2005

Hi
My conf it's very very simple. But i use MS Win 2008 r2
----------
proto tcp
port 5555
dev tap
ca "C:/Program Files (x86)/OpenVPN/easy-rsa/keys/ca.crt"
cert "C:/Program Files (x86)/OpenVPN/easy-rsa/keys/server.crt"
key "C:/Program Files (x86)/OpenVPN/easy-rsa/keys/server.key"
dh "C:/Program Files (x86)/OpenVPN/easy-rsa/keys/dh1024.pem"
server 192.168.12.0 255.255.255.0
keepalive 10 120
client-to-client
tcp-nodelay
---------------------------
I have 100mbits internet chanel and other side also 100mbits
But in tunnel is maximum 10 mbits.
Why it's happen i don't know :-((

janjust

you're using 'proto tcp' which always causes a slight performance decrease; try adding

mssfix 1300

to both client and server configs; you could also try lowering the MTU on the tap-win32 adapter on both ends, using

tun-mtu 1400

plus a NETSH.EXE or registry fix to lower the value on the adapter itself.

aleksander_2005

janjust wrote plus a NETSH.EXE or registry fix to lower the value on the adapter itself.

understand this command
my screen

janjust

the tap-win32 adapter will ALWAYS report 10 Mbps (like the tun adapter does on linux). The actual speed you have to measure using a tool like 'iperf' or speedtest.net

aleksander_2005

hmmm ... i think it's maximum VPN perfomence. 192*** it's other side on VPN.
All side have 100 mbits/s

janjust

change the tunnel mtu to 1400 on both sides using

tun-mtu 1400

and run the following netsh commands:
* find the subinterface number for the tap-win32 adapter

netsh interface ipv4 show subinterfaces

* change the mtu

netsh interface ipv4 set subinterface <N> mtu=1400

and test the transfer speed again; play a bit with the MTU value (e.g. 1400->1100->1300->1200) to see what gives you the best performance