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Question OpenVPN server speed on Archer C1200?

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DSD27

Junior Member
I'm running a OpenVPN server (udp) in my Archer C1200 and I never get more than 8Mbps... Is it normal for this router? Or are there some settings I could tweak?
I've seen people on the internet saying they get 80Mbps with this router, or the older C7. I have a 100/100 connection on the server and 100/50 on the client, both through ethernet cable.

I tried disabling QoS and I think it imporeves like 1 Mbps.. I tried enabling Nat Boost, made nodifference. Nat Boost can't be enabled at the same time as QoS.
I think this router has a 900Mhz CPU, is it actually good enough or people may be wrong when they say they have all that speed?
 
When search the Internet for this topic you find many people complaining that the class of Router like the the C7 or Asus (and others) with similar CPU perform slow with their VPN.

Many people in the world use the Internet with 8Mb/s. If you really need faster VPN (not for macho purposes) buy a Router of Higher class.

There are Millions that pay close to $100.000 for fancy cars that do not Really providing more functionality than a $30.000 car.

Lucky for us getting a better Router is just $100
more.

The Asus RT-AC86U is $170 it is dual core that allocates 900mhz to encryption from each core.


😎
 
To verify the OpenVPN performance, I setup OpenVPN server (Windows 7) and client (Windows XP) in virtual machines (host is an old 2.5GHz Q8300 CPU system) and test http download 760MB file.

With OpenVPN running, network throughput is merely 10-11Mbps, without OpenVPN, the throughput jumps to 60-70Mbps. (reasonable on a HDD system)
 
Protectli, a firewall appliances specialist.

https://protectli.com/product-comparison/

==

The following table shows the company's products that supports AES-NI encryption feature.

Even model FW2B (dual core Celeron J3060 2.4 GHz ), FW4B (quad core Celeron J3160 2.24 GHz ) & FW4A (quad core Intel Atom E3845 1.9 GHz) throughput all drop from unencrypted 940Mbps LAN speed to OpenVPN AES-256 encrypted ~110Mbps. 7 to 8 times slower.

The verdict? Processor matters, and it matters a lot for VPN traffic.

https://protectli.com/kb/openvpn-performance/Untitled.png
 
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I get about 50mbps running a VPN on my pfsense box, its got a slower CPU, a dualcore 1.8Ghz celeron that does not support AES-NI, but hey it draws 15w loaded and is fanless so theres that lol.

VPN's are brutal on the CPU, i have since switched to my File server running my VPN(i5 4670 CPU, supports AES-NI) and can now obtain full line speed through my VPN(650mbps) and not even max 2 cores out on it.
 
One can not compare a Stand alone PC (like what pfsense uses) to a Wirless Router, based only on the CPU Speed.

Though the words (CPU, Speed) are the same, the real functionality is totally different.


😎
 
One can not compare a Stand alone PC (like what pfsense uses) to a Wirless Router, based only on the CPU Speed.

Though the words (CPU, Speed) are the same, the real functionality is totally different.


😎

Obviously Arm vs x86 is tough to compare, the point i was trying to make though is that regardless of Arm or x86 hardware you are going to want Both AES-NI instructions and a fast CPU to get good VPN speeds. No sub $100 router is going to give you fast speeds, they simply dont have the CPU horsepower.
 
OpenVPN is only single threaded, yet TP-link Archer C1200's BCM47189 ARM processor is also just a single core CPU.

So the CPU has to spend most of its power to deal with the encryption.
 
You can try PPTP or L2TP proxy as VPN connection instead of OpenVPN. It's less harsh on CPU (also less encrypted).
I manage 30mbps with L2TP on a 10 year old tp-link WR1043ND. My connection is 10/100.
 
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