AC68U WiFi slower in AP mode vs Router mode?

[jjrs]

Hello,

I recently purchased a hardware firewall and have set it up at home. With this installed, my network topology is basically internet--->firewall--->switch--->AC68U

In that configuration, download speed are about 50MBps, whereas before when my AC68U handled router/AP duties, I would get 60-61MBps.

I initially thought it was the firewall but there is almost zero load on it. Upload speeds are also unaffected and I am getting the full 60-61MBps that the AC68U can do wirelessly.

Any ideas as to what could be causing this? Thanks!

 

[L&LD]

What firmware are you using? When was the last time you did a full reset to factory defaults on the RT-AC68U?

 

[jjrs]

What firmware are you using? When was the last time you did a full reset to factory defaults on the RT-AC68U?

I am running the latest stock Asus firmware. It's been a year or so since I reset it last.

 

[L&LD]

I am running the latest stock Asus firmware. It's been a year or so since I reset it last.

'Latest stock Asus firmware' doesn't mean anything.

Since it is just a simple switch to enable AP mode, I would suggest doing a full reset on the unit as a first step.

Myself, I would also reflash the latest firmware too (even if it's the same as what you have now) and then do another full reset to factory defaults and then log on to the router and convert it to AP mode. Make sure you also format the JFFS partition on the next boot and then reboot the router 3 times in ~15 minutes or so, leaving it idle about 5 to 10 minutes between reboots.

 

[wouterv]

A few thoughts:
If the last reset of your RT-AC68U was over a year ago, it definitely does not run the latest firmware, over the past year there have been 6 new firmware releases.
Any hardware or software in between a network connection will cause some slowdown (the firewall will take some and the switch will take some).
For any data you retrieve from the Internet, the firewall shall do some checks and slows the throughput a bit (otherwise the whole thing makes no sense).
A decrease from 60 Mbps to 50 Mbps is almost nothing compared to what the RT-AC68U can do (in my setup it hits the 600 Mbps with the right client), what does your Internet subscription allow?

 

[jjrs]

'Latest stock Asus firmware' doesn't mean anything.

Since it is just a simple switch to enable AP mode, I would suggest doing a full reset on the unit as a first step.

Myself, I would also reflash the latest firmware too (even if it's the same as what you have now) and then do another full reset to factory defaults and then log on to the router and convert it to AP mode. Make sure you also format the JFFS partition on the next boot and then reboot the router 3 times in ~15 minutes or so, leaving it idle about 5 to 10 minutes between reboots.

Sorry, I wasn't clear in my post. I was running Version 3.0.0.4.384.81049. That release worked fine when my AC68U was the router/switch/AP but when I switched to a standalone router/switch and made the AC68U my AP, that's when I started noticing the slow speeds with NNTP downloads. Regular downloads via http seem fine, and I can max out my wireless connection, as are uploads, speedtests, and etc.

I factory reset the router, reinstalled the firmware, cleared NVRAM via CFE, installed different firmware and tried them via the CFE server (stock, FreshTomato, and Merlin). FreshTomato speeds were abysmal and stock/Merlin were about the same.

It's very strange, there is no load on my router, nothing is being blocked by the firewall, NAT, or etc. The router is also not fully under load. What I am seeing though is that everything but NNTP speeds works as intended so I'm assuming that it might be something in with the software. It also does NOT seem to affect speeds when connected to a different PC that has AC1300 support.

A few thoughts:
If the last reset of your RT-AC68U was over a year ago, it definitely does not run the latest firmware, over the past year there have been 6 new firmware releases.
Any hardware or software in between a network connection will cause some slowdown (the firewall will take some and the switch will take some).
For any data you retrieve from the Internet, the firewall shall do some checks and slows the throughput a bit (otherwise the whole thing makes no sense).
A decrease from 60 Mbps to 50 Mbps is almost nothing compared to what the RT-AC68U can do (in my setup it hits the 600 Mbps with the right client), what does your Internet subscription allow?

Please see above, my connection is about 550Mbps.

 

[L&LD]

Not clear if you're flashing the firmware first and then resetting to factory defaults? The way it is phrased now it seems the order is wrong.

 

[jjrs]

Not clear if you're flashing the firmware first and then resetting to factory defaults? The way it is phrased now it seems the order is wrong.

Before I flashed anything, I cleared the NVRAM using the CFE server, then flashed the firmware. After I rebooted, I reset the router again.

I wrote that as more of a list of the things I've tried and done, I should have been clearer. I'll leave it up as is since I've clarified it here.

Do you have any thoughts as to why this could be happening? I've never seen anything like this before, and I don't really understand why it's happening.

 

[ColinTaylor]

What device is the router now, the firewall or the (smart?)switch? What are the makes and model numbers of these devices?

 

[follower]

Hello,

I recently purchased a hardware firewall and have set it up at home. With this installed, my network topology is basically internet--->firewall--->switch--->AC68U

In that configuration, download speed are about 50MBps, whereas before when my AC68U handled router/AP duties, I would get 60-61MBps.

I initially thought it was the firewall but there is almost zero load on it. Upload speeds are also unaffected and I am getting the full 60-61MBps that the AC68U can do wirelessly.

Any ideas as to what could be causing this? Thanks!

Are you using QoS?

 

[jjrs]

Are you using QoS?

There is no QoS in AP mode, at least not to my knowledge. There is no QoS running on the switch or the firewall/router either.

What device is the router now, the firewall or the (smart?)switch? What are the makes and model numbers of these devices?

The router/firewall is a pfSense appliance running on an i5-7500/intel i350-t4 nic. The switch is a TP Link TL-SG108E

 

[ColinTaylor]

From what you've said there is no problem at all other than for NNTP traffic. With all other types of traffic you get full speed in both directions.

So this can't be a problem with the AP per se because it cannot differentiate between different types of traffic. It's all Ethernet as far as it is concerned. So we can deduce that it's either an issue elsewhere in your LAN or an issue on the internet side (ISP).

My first suspicion would be that your ISP is throttling the NNTP traffic. Why now and not with your previous setup? The only thing I can think of that would have changed is your public (WAN) IP address. This IP address is usually linked to the MAC address of the WAN interface and that has now changed with the pfSense box. Or maybe your new IP address is blacklisted/restricted in some way by the NNTP server.

 

[jjrs]

From what you've said there is no problem at all other than for NNTP traffic. With all other types of traffic you get full speed in both directions.

So this can't be a problem with the AP per se because it cannot differentiate between different types of traffic. It's all Ethernet as far as it is concerned. So we can deduce that it's either an issue elsewhere in your LAN or an issue on the internet side (ISP).

My first suspicion would be that your ISP is throttling the NNTP traffic. Why now and not with your previous setup? The only thing I can think of that would have changed is your public (WAN) IP address. This IP address is usually linked to the MAC address of the WAN interface and that has now changed with the pfSense box. Or maybe your new IP address is blacklisted/restricted in some way by the NNTP server.

It's not the ISP, if I connect directly to the switch, I max out my connection using the same servers, # of connections, and port config, WAN IP and etc .

There are no firewall rules blocking NNTP ports, and even if there were, I'm not sure it would affect the setup as I have tested ports 80, 81, and 563 for SSL and others for non SSL connections.

I also tested a triple antenna client, which is capable of AC1300, that one can get speeds between 55-60 MBps. The client that I am getting lower speeds has an intel AC 9560, which is capable of gigabit wifi but only on 160 MHz channels.

The thing is, before I set up my current network (when the AC68U was router/switch/etc), I was able to hit the max WiFi speeds it could push (500ish Mbps). This is all very odd haha, I'm going to do some more tinkering, hopefully I can figure something out. Thank you for helping me troubleshoot!!

 

[ColinTaylor]

When you switched to your new setup did you physically move the AC68U? 5GHz is very susceptible to blocking/reflections from other objects so even small changes can make a difference. Also, is the AC68U using the same channel and bandwidth as before?

Can you confirm that you're talking about bytes in the download speed, i.e 50MBps (400Mbps) vs. 60MBps (480Mbps).

 

[jjrs]

When you switched to your new setup did you physically move the AC68U? 5GHz is very susceptible to blocking/reflections from other objects so even small changes can make a difference. Also, is the AC68U using the same channel and bandwidth as before?

Can you confirm that you're talking about bytes in the download speed, i.e 50MBps (400Mbps) vs. 60MBps (480Mbps).

It moved about ten inches, it's next to the switch now. Yes, same channel/bandwith setup. I did a survey using WinFi on my laptop and used an app on my phone to see if there were other networks on my channel (I had done this initially when I set up the router) and there are none on my channel.

I can confirm that all of the notations that I used (MBps, Mbps, and etc. are correct.). I corrected my previous post where I said 600Mbps, it was supposed to be 500Mbps.

 

[jjrs]

If anyone here has time, can you please test this on your end? I'd be very grateful if someone can explain to me what the hell is going on here

I have used the latest releases of both Merlin and AsusWRT and still see the same results. I am unable to figure out why there is a difference between the speeds between the two modes using the same network, same ISP, same client, same files, etc.

I just did the full test again, reset the router, installed the stock firmware and used the same settings as I had before. In router mode, I'll get 60-62 MBps and as soon as I switch to AP mode, I get 40-50 MBps.

Is there a hidden QoS functionality in AP mode by any chance?

 

[jass]

If anyone here has time, can you please test this on your end? I'd be very grateful if someone can explain to me what the hell is going on here

I have used the latest releases of both Merlin and AsusWRT and still see the same results. I am unable to figure out why there is a difference between the speeds between the two modes using the same network, same ISP, same client, same files, etc.

I just did the full test again, reset the router, installed the stock firmware and used the same settings as I had before. In router mode, I'll get 60-62 MBps and as soon as I switch to AP mode, I get 40-50 MBps.

Is there a hidden QoS functionality in AP mode by any chance?

Hi,

I suspect pfSense to be the culprit in this case. Yes pfSense is a fantastic router software which allow you to tweak almost anything. But it comes at cost, there are an incredible amount of settings which might give you all sorts of problems too...

When you use router mode, the Asus box handles everything. AFAIK in AP mode the Asus box only handles the wifi part and the pfSense box handles everything else.
I believe there are a setting somewhere in pfsense which somewhat differ from what Asus use, and therefore the different speed result between the two modes...

 

[jjrs]

Hi,

I suspect pfSense to be the culprit in this case. Yes pfSense is a fantastic router software which allow you to tweak almost anything. But it comes at cost, there are an incredible amount of settings which might give you all sorts of problems too...

When you use router mode, the Asus box handles everything. AFAIK in AP mode the Asus box only handles the wifi part and the pfSense box handles everything else.
I believe there are a setting somewhere in pfsense which somewhat differ from what Asus use, and therefore the different speed result between the two modes...

Hi, thanks for the suggestions. I tried something different, I removed the pfsense box from the network and used an old Asus N56U which I had laying around, this is gigabit capable (wired). I turned off all of the wireless features on the N56U and used it as a router so the topology now was ONT--->N56U--->AC68U-AP.

I saw the same exact results, as soon as it goes into AP mode, the AC68U is gimping Wireless speeds.

When using the pfsense box, the load on that system was minimal at best and the machine was almost never under load when I was testing this. It also didn't have any of the IPS packages or etc. enabled, or anything else that should affect speeds. QoS was also not on.

This is all very strange, I guess I'll just have to deal with it until I get a better AP.

 

[Val D.]

I saw the same exact results, as soon as it goes into AP mode, the AC68U is gimping Wireless speeds.

Then test the method to turn a router with no AP mode into an AP:

- leave the RT-AC68U in Router Mode
- disable DHCP on it
- set a static IP for it
- connect your primary router to a LAN port (not WAN)

Not sure if this is the case with RT-AC68U, but on some routers WAN-to-LAN traffic (going through CPU) is slower than LAN-to-LAN (direct switching). NTP may not work with this method though, but test and see what happens.

 

[jass]

Hi, thanks for the suggestions. I tried something different, I removed the pfsense box from the network and used an old Asus N56U which I had laying around, this is gigabit capable (wired). I turned off all of the wireless features on the N56U and used it as a router so the topology now was ONT--->N56U--->AC68U-AP.

I saw the same exact results, as soon as it goes into AP mode, the AC68U is gimping Wireless speeds.

When using the pfsense box, the load on that system was minimal at best and the machine was almost never under load when I was testing this. It also didn't have any of the IPS packages or etc. enabled, or anything else that should affect speeds. QoS was also not on.

This is all very strange, I guess I'll just have to deal with it until I get a better AP.

Just a long shot, since all security and advanced stuff being handled by the router and not the AP, have you tried with an old fw, like Merlin Legacy 380.70 to see if it behaves any different then...