RT-AC88U / Open VPN speeds

[G F]

Hi All,

I believe i may have a possible configuration issue with my RT-AC88U as i'm getting poor OpenVPN speeds. My ISP recently fixed a problem and improved my speed but i havent seen any change on my VPN speeds.

I'm currently running the latest stable firmware and have performed a factory reset.

My native connection can achieve over 13Mbps.
PIA Windows VPN client can achieve 11Mbps
Asus/Merlin OpenVPN connection can only achieve 8Mbps

I have tried various encryption types
aes-128-cbc/sha
AES-256/SHA256
AES-128-GCM

and other tweaks like
Nat acceleration enabled /disabled
QOS
Compression
fast-io

I've also tried another VPN provider and also got ~8Mbps

Am i expecting to much from my router or is there anything else I should look at?

Appreciate your assistance.

 

[D_Day]

I have the AC68U and use ExpressVPN and I get around 16Mbps on OpenVpn but I almost max out my connection speed using their app on my devices.
I’ve tried multiple configurations and can’t get anymore speed so it’s not just your model.
I may be missing something to so if anyone else can help it would be appreciated.

 

[kfp]

Is there a speed difference between LAN or Wifi?

 

[somms]

https://i.imgur.com/1ORcgLZ.png

https://i.imgur.com/hv2LARi.jpg


End to end TAP udp via port 1194 OpenVPN tunnel throughput pictured above of XMission's Utopia active ethernet fiber network 1 Gbps up/down throughput on both ends.

https://i.imgur.com/z3vpFiE.png

https://i.imgur.com/2jU9pZ3.jpg


Pictured above is the normal https://xmission.com/utopia throughput attained on either end of this test over the Utopia fiber network...


FWIW: Although not an AC88U, my RT-AC86U gateway OpenVPN Server router is able to achieve the above throughput for remote OpenVPN clients running under Merlin's latest RT-AC86U_384.6_alpha2-g5b076fc87 test build...

 

[CheffieCT]

Hi all and I am a newbie and came across this forum and I have a serious question as I need clarification on using OPENVPN client and on the ASUS routers.

I have a DSL-AC56U router which is a combo of VDSL and Wireless router connected as Wireless router with Fibre. The issue is that I know Merlin doesn't support and DSL-XXX models and OPENVPN client (connecting to TigerVPN) is really slow comparing using OPENVPN on my Linux desktop (I can't even get 10% of my 100Mbps on the Asus OPENVPN). Now I am thinking about getting a new wireless router - RT-AC68U and I want to flash it with Merlin firmware. The concern and uncertainty I have is that how much of the improvement will Merlin firmware make and also will it be able to utilize more than one CPU seeing AC68U is dual core? I had thoroughly went through all the discussions but nothing has been confirmed. otherwise the next best option would be getting a Linksys with hardware crypo (acceleration) if AC68U doesnt support it regardless of the firmware? I hope this is a valid question and thank you for providing such great software and forum for all people like us.

Thanks,

cheffie

 

[Lancairone]

I'm having a similar issue with my Open VPN on an AC88U. I get 95 Mbps throughput without the VPN turned on and only ~33 Mbps with a single VPN in relatively close proximity to my location. I am using TCP (rather than UDP) protocol.

 

[G F]

Is there a speed difference between LAN or Wifi?

Not really. I just re-ran the tests this morning and its currently 6.4 via ethernet and 6.3 via wifi. I should have noted in my original post that all my tests are being performed over ethernet.

Thanks Somms. they are some impressive stats. I have read that the RT-AC86U is excellent for openVPN, especially when you have a higher connection speed but in my location thats not possible, i'm stuck with ADSL.

Thanks for posting D_Day and Lancairone. At least i'm not alone.

What i dont understand is 55-65% of my connection speed normal openvpn performance on a ac88u and if not what other things should I try or investigate.

I should add i'm currently running a fresh manual build. No firewall scripts/adblocking etc have been installed.

 

[kfp]

I should add i'm currently running a fresh manual build.

Like you compiled it yourself?

 

[G F]

Like you compiled it yourself?

I meant I haven't restored any config or scripts from backup. It's basically a fresh install with openvpn configured.

 

[kfp]

I meant I haven't restored any config or scripts from backup. It's basically a fresh install with openvpn configured.

Ah, and which version is this?

 

[G F]

I'm running 384.5

 

[G F]

I've have managed to borrow an RT-68u to do some additional testing.

Its also running 384.5 and i'm getting comparable speeds between the RT-68u and 88u.
What Connection Type Test Server TPC/UDP Encryption NAT Acceleration Compression Download Mbps Upload Mbps
AC-88u 380.68.4 Ethernet VPN PIA Open VPN Sydney UDP aes-128-cbc/sha1 Enabled Disabled 6.6 0.8
AC-68u 380.68.4 Ethernet VPN PIA Open VPN Sydney UDP aes-128-cbc/sha1 Enabled Disabled 6.6 0.7

Does anyone have any suggestions?

Thanks

 

[kfp]

Does anyone have any suggestions?

In OP you mentioned QoS, is it on or off?
Maybe posting your ovpn config?

 

[G F]

I have tried QOS enabled which was my original state (as I collected traffic stats monitored by IP)

As part of the troubleshooting I have moved to QOS disabled with NAT Acceleration switched on but I didn't see any changes in speed.

The only noticeable change in speed that I can replicate is when I switch between UDP and TCP. TCP being slightly faster. 7.5-8mb depending on time of day.

Here are my VPN client settings

[VPN Client]
vpnc_dnsenable_x="1"
vpn_client1_addr="xxxx.privateinternetaccess.com"
vpn_client1_adns="3"
vpn_client1_bridge="1"
vpn_client1_cipher="AES-128-CBC"
vpn_client1_comp="adaptive"
vpn_client1_crypt="tls"
vpn_client1_desc="Client 1"
vpn_client1_digest="SHA1"
vpn_client1_enforce="0"
vpn_client1_hmac="-1"
vpn_client1_if="tun"
vpn_client1_local="10.8.x.x"
vpn_client1_nat="1"
vpn_client1_ncp_ciphers="AES-128-GCM:AES-256-GCM:AES-128-CBC:AES-256-CBC"
vpn_client1_ncp_enable="1"
vpn_client1_nm="255.255.255.0"
vpn_client1_password="password"
vpn_client1_port="502"
vpn_client1_proto="tcp-client"
vpn_client1_remote="10.8.x.x"
vpn_client1_reneg="0"
vpn_client1_rgw="1"
vpn_client1_tlsremote="0"
vpn_client1_userauth="1"
vpn_client1_username="username"
vpn_client1_useronly="1"
vpn_client1_verb="1"

 

[CheffieCT]

I'm having a similar issue with my Open VPN on an AC88U. I get 95 Mbps throughput without the VPN turned on and only ~33 Mbps with a single VPN in relatively close proximity to my location. I am using TCP (rather than UDP) protocol.

You are still lucky. I get up to 70mbps/100 from my desktop openvpn (linux) and I get 7mbps/100mbps for my ASUS openvpn!

 

[CheffieCT]

I've have managed to borrow an RT-68u to do some additional testing.

Its also running 384.5 and i'm getting comparable speeds between the RT-68u and 88u.
What Connection Type Test Server TPC/UDP Encryption NAT Acceleration Compression Download Mbps Upload Mbps
AC-88u 380.68.4 Ethernet VPN PIA Open VPN Sydney UDP aes-128-cbc/sha1 Enabled Disabled 6.6 0.8
AC-68u 380.68.4 Ethernet VPN PIA Open VPN Sydney UDP aes-128-cbc/sha1 Enabled Disabled 6.6 0.7

Does anyone have any suggestions?

Thanks

What would be the normal speed? this looks very bad bad bad connection speed!

 

[kfp]

It’s pretty pointless to compare OpenVPN speeds on the router vs on your PC; your PC CPU is way more powerful and almost guaranteed to have a crypto chip to speed up the encryption, so it’s gonna blow Asus performance out the water most of the time.

What we could investigate further though, is if two routers of the same model (so same CPU), with the same firmware version (so same OpenVPN+OpenSSL version) to have different speeds. Then we can be pretty confident that either the config or the VPN provider is the causing the slowdown, and it’ll probably be down to which cipher suite the client and server end up using for the tunnel.

 

[CheffieCT]

It’s pretty pointless to compare OpenVPN speeds on the router vs on your PC; your PC CPU is way more powerful and almost guaranteed to have a crypto chip to speed up the encryption, so it’s gonna blow Asus performance out the water most of the time.

What we could investigate further though, is if two routers of the same model (so same CPU), with the same firmware version (so same OpenVPN+OpenSSL version) to have different speeds. Then we can be pretty confident that either the config or the VPN provider is the causing the slowdown, and it’ll probably be down to which cipher suite the client and server end up using for the tunnel.

Well, this is my issue and question about buying a new router and also reading through peoples' post using merlin or stock firmware. And also talking about hardware crypto on Linksys routers and not Asus. So I think we are ASSUMING these Dual core routers are under power to encryp or decrypt OPENVPN but rather the architects aren't being utilized properly by certain model or manufacturer?

 

[D_Day]

Not really. I just re-ran the tests this morning and its currently 6.4 via ethernet and 6.3 via wifi. I should have noted in my original post that all my tests are being performed over ethernet.

Thanks Somms. they are some impressive stats. I have read that the RT-AC86U is excellent for openVPN, especially when you have a higher connection speed but in my location thats not possible, i'm stuck with ADSL.

Thanks for posting D_Day and Lancairone. At least i'm not alone.

What i dont understand is 55-65% of my connection speed normal openvpn performance on a ac88u and if not what other things should I try or investigate.

I should add i'm currently running a fresh manual build. No firewall scripts/adblocking etc have been installed.

My speeds are the same over Ethernet and wireless.
I have an Xbox one(Ethernet) connected and an Android box(wireless)
I have a very basic configuration, NAT acceleration is disabled, no QOS only parental controls running really. I have tried so many different tweaks and the max speed I can get is around 17mbps dl and 14mbps upload.
I use ExpressVPN and their config file is pre done and just loaded into OpenVpn.
I’m also on VDSL due to location and get max download speed of 60mbps and 20mbps upload.
It’s just frustrating when I can load their app on a device and nearly max my connection speed yet on get a 1/4 of the speed through OpenVpn.
It’s not a new problem though, it was the same on the last 2 updates.
If it’s hardware related then I don’t have a problem because I’ll just buy another router at some point but I actually like the AC68U and I’ve had it for a couple of years and it’s not let me down yet.
I also can’t go over to the stock firmware because I need option 61 because my provider doesn’t support third party equipment and I’m not prepared to piggyback their router as Iose a lot of merlons features.

 

[G F]

What would be the normal speed? this looks very bad bad bad connection speed!

I'm from Australia. The land of slow internet. I'm on ADSL2 and that is my normal speed unfortunately.