openvpn slow very slow on ASUS RT-AC66U

[Ervin Valentin]

I just signed up with PIA and have established a VPN tunnel on my ASUS RT-AC66U router running ASUS/Merlin firmware 380.57. I have a fiber line with 115Mbps down and 850 Mbps up measured with speedtest.net wired to the router, non VPN.
Activating the VPN tunnel on one of our iMac I can't squeeze more then 10/10 Mbps out of the VPN tunnel .... Merlin is configured as advised here https://support.privateinternetaccess.com/Knowledgebase/Article/View/142 ....

Seems like more people have the same issue .... pls see below

https://www.privateinternetaccess.com/forum/discussion/comment/39889/#Comment_39889

Installing a PIA openVPN Client on the iMac I have a speed of 105/160 Mbps ... brilliant

Pls advice

 

[RMerlin]

That's the best you will be able to squeeze out of a 600 MHz CPU. Maybe 20 Mbps at most with the right cipher.

 

[wag3719]

It isn't just the router causing the slow down, it is also on the VPN server side. I'm using IPV and a faster router and all I get is 10 MBPS with OpenVPN. This is why I'm using PPTP on my router. I'm getting a 4x throughput improvement. If you don't need maximum security encryption, give it a try.

 

[CaptainSTX]

It isn't just the router causing the slow down, it is also on the VPN server side. I'm using IPV and a faster router and all I get is 10 MBPS with OpenVPN. This is why I'm using PPTP on my router. I'm getting a 4x throughput improvement. If you don't need maximum security encryption, give it a try.

With PPTP you are getting minimal security that can be easily hacked if someone choses to do so. While it might be better than no VPN its not by much.

In addition in testing it on my setup I didn't see much improvement in using PPTP vs Open VPN.

 

[wag3719]

I definitely see a rather dramatic throughput improvement using PPTP instead of OpenVPN with IPV. I have gone back and forth enough times that I know for a fact that this is the case. OpenVPN requires a LOT more horsepower to run, on both ends of the tunnel. I don't really need maximum encryption security for what I'm doing anyway, I just want to keep my ISP (and other interested parties) from easily seeing what I'm doing and where I'm going. A VPN service with a no-logging policy and PPTP is good enough for this purpose. Nobody, including the NSA, is really going to be interested enough in my data stream to try and hack it.
The OP should see an even bigger throughput improvement than I am getting using PPTP with his fiber connection, I only have a 50 MBPS Internet connection. The OP should also try some of the different VPN servers that PIA has available, I was able to get some throughput improvement there as well.

 

[Ervin Valentin]

That's the best you will be able to squeeze out of a 600 MHz CPU. Maybe 20 Mbps at most with the right cipher.

two questions ...
a) what would the right cipher be ?
2) do you have any experience what can be squeezed out of a CPU with 800 Mhz, 1 GHz etc ?

 

[RMerlin]

two questions ...
a) what would the right cipher be ?

You are bound to use whichever cipher your tunnel provider uses. If they offer different ciphers, AES-128-CBC is recommended. I'm able to push the RT-N66U (same CPU) to around 20 Mbits.

2) do you have any experience what can be squeezed out of a CPU with 800 Mhz, 1 GHz etc ?

The 800/1000 MHz dual core ARM routers such as the RT-AC68U can hit close to 50 Mbps (again, only tested with AES-128-CBC).

I haven't measured the RT-AC88U 1.4 GHz CPU, but it's the same architecture, so progress should be somewhat linear to the 1 GHz one.

 

[Ervin Valentin]

You are bound to use whichever cipher your tunnel provider uses. If they offer different ciphers, AES-128-CBC is recommended. I'm able to push the RT-N66U (same CPU) to around 20 Mbits.



The 800/1000 MHz dual core ARM routers such as the RT-AC68U can hit close to 50 Mbps (again, only tested with AES-128-CBC).

I haven't measured the RT-AC88U 1.4 GHz CPU, but it's the same architecture, so progress should be somewhat linear to the 1 GHz one.

I'm roughly at 15 Mbps because of your advice (thx ) and the conclusion is that the router was the bottleneck, using PIA's client I'm above 100/100 Mbps .... I'll start looking for a rt-ac68u

Btw what's the idea of being able to set up several VPN clients ?

 

[RMerlin]

I'm roughly at 15 Mbps because of your advice (thx ) and the conclusion is that the router was the bottleneck, using PIA's client I'm above 100/100 Mbps .... I'll start looking for a rt-ac68u

Btw what's the idea of being able to set up several VPN clients ?

Sometimes you need on-demand VPN clients (you manually connect a specific one based on your need). Or, you could have one client to connect back to your office, and another to a tunnel provider.

 

[Ervin Valentin]

Sometimes you need on-demand VPN clients (you manually connect a specific one based on your need). Or, you could have one client to connect back to your office, and another to a tunnel provider.

.... and you do the selection through the Policy Rules / makes sense .... thank you