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Re: [Openvpn-users] Slow Performance with Windows Clients

I am using speedtest.net to test the speed since all traffic (including web browsing) is going through the vpn. On the Mac OS X machine, I see a slowdown of 10%-20% with the vpn as compared to no vpn and on the windows machine I see a slowdown of 30%-50% with the vpn as compared to no vpn. The server has a gigibit WAN connection, so there should be hardly any slowdown (only vpn overhead).


On 5/28/07, Timm Wimmers <timm@xxxxxxxxx> wrote:
ournixnation@xxxxxxxxx schrieb:
> I have been doing some research and this seems to be a common problem: a
> linux server and a windows client. If someone could help me determine
> why my
> windows client is slow when using my linux server, I will donate $50 USD in
> your name to the openvpn project. I really need to figure this out, and I
> can't seem to figure it out myself.

What do you mean with "slow down", did you mean the connection speed
i.e. transferrate? Which protocol does your clients use to connect tothe
server? SMB, NFS, FTP?

With FTP over the tunnel I get nearly the speed that my DSL line can

FTP Upload:      35 KB/s        - to OpenVPN Server
FTP Download:   230 KB/s        - from OpenVPN Server

With Samba I get horrible results:

SMB Upload:     26 KB/s         - to the server
SMB Download:   32 KB/s         - from the server
                ^^^^^^^ (!)

This did I find out the last three days: If you are using Samba
(SMB/CIFS), than that's the possible reason why your clients are slow.
SMB/CIFS isn't a efficient protocol. Much of the packets that goes
through the tunnel are just "blahs and blubs" and really small (between
50 and 100 bytes), so the overhead (managing packets) goes up and your
transferrate goes down.

Mmh, because I've the same problem as you, I would also donate 50EUR to
OpenVPN (in the name of the contributer who solves this(!)), if anybody
can bring up the transferrate to same speed as FTP (or nearby) using