VPN speed much lower than expected

[llarsx]

I have a darkfighter camera with memory card (128 GB) and have set up with mail when something happens. When I receive such mail I open the vpn connection and if I find the accident important or interesting, I download the actual video.

My broadband in my cottage where the camera is, has about 15-20 Mips upload (30-40 down) and home I have about 100 Mips both up and down. The download vpn speed is very poor as the videos are about 60 MB and the download use normally 1 1/2 min.

In my cottage I have wireless broadband with an asus router behind the wireless, using openvpn. Home fiber (without vpn).

Is something wrong in my setup or is such numbers normal?

 

[catcamstar]

Hi @llarsx, you can actually tweak a lot with OpenVPN, which may/may not have an impact on your situation:

• pick another encryption algorithm: the more complex, the higher the work for the ASUS, the slower the connection. An indication is the CPU usage when you download footage.
• pick UDP protocol over TCP
• change MTU sizes

I use the first two tricks and it helped me out a lot!

If you want to know the why's and the ooh's:

https://community.openvpn.net/openvpn/wiki/Gigabit_Networks_Linux?

or Improving OpenVPN Performance or google on "improve performance openVPN".

Good luck!
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[llarsx]

Thanks catcamstar. You are a good friend.
I shall investigate your suggestions but realize that any change will demand a new client1.ovpn and that is something I like to do when I am in my cottage where the camera is. Therefore I can't comfirm any result now. I can of course view the asus usage through the vpn at the same time the videos being transferred. I use UDP and AES-128-CBC and compression = Disable.
But thanks again.

 

[catcamstar]

You are welcome!

What you càn do in the meanwhile: in ASUS you can deploy a second VPN server (instance_2), off course on another port than instance_1. You can then download the client1-instance2.ovpn file through the WAN webportal (which I suspect you opened as you can see the ASUS usage KPI's).

Good luck and enjoy tweaking
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[llarsx]

Thanks again, catcamstar.

 

[llarsx]

Not so very good when I have 18 Mips upload available just now.

 

[catcamstar]

Okay, so let's work around these numbers. That graph shows us around 800-900 KB/s, which is, times 8, 6400Kbps, so 6.4Mbps. For a hardwired line of 15-20Mbps, that is not really skyhigh.

What happens if you go to less encryption and higher compression. Compression can be counterproductive (but at least you will save some bits being transferred over and forth). This is trial and error, the chipset on the ASUS is not a High Performant Computer, some algorithms perform better than others. You can find some other insights here: Asus Router, Rmerlin Firmware and OpenVPN options for best performance

You might need to tweak (balance) a bit between "performance" and "security", but I'm pretty sure you can go higher than what you are showing. Other solution might be deploying a NUC for the VPN server (I've even seen people doing this on a NAS to do off-site NAS-synching).

Good luck!
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[llarsx]

Hi catcamstar. Thanks again. I shall certainly investigate further and read the links you mention.
Best regards
llarsx