What's new

RT-AC68U in Media Bridge mode won't go faster than 288.9 Mbps. Main router = AX-88U. RSSI @ AC-68U is a strong -35dBm.

  • SNBForums Code of Conduct

    SNBForums is a community for everyone, no matter what their level of experience.

    Please be tolerant and patient of others, especially newcomers. We are all here to share and learn!

    The rules are simple: Be patient, be nice, be helpful or be gone!

Update: finally reverted the AC1900P to STOCK Asus firmware.

The media bridge performance is no better. FreshTomato has at least 5x faster throughput.

@RMerlin, to bring you up to speed: a third-party firmware project forked from TomatoUSB has somehow managed to get significantly better 5GHz throughput between access points. I've tested two different Broadcom-based APs with Cortex A7 dual core CPUs at similar speeds. Both are configured in "media bridge" or "wireless ethernet bridge" mode. The stated data rate is 1300Mbps. RSSI is between -35 and -45 dBm. The access points are placed in adjacent rooms, ~15 feet total distance, including one layer of drywall in a wood frame house.

A Netgear R7000 running FreshTomato firmware achieves 600-700Mbps bidirectional throughput with an AX88U as the base AP.

An AC1900P running FreshTomato achieves the same level of performance. The same AC1900P running Asus stock or Asuswrt-merlin sees much lower throughput, ranging from 60-150Mbps.

Any thoughts about filing a bug or performance enhancement request with Asus? Any other tests you'd like me to perform? Is this a known issue?

Thanks!
That is crazy... great detective work.
 
Did you try to set the RT-AC1900P as AiMesh node instead of Media Bridge, then wire your client devices to it and try the throughput?
 
Just to chime in. AX86U main router. AC68U/AC66U_B1 as media bridge. ISP speed is 500mbps DOWN / 100mbps UP.

AX86U with Merlin 386.3_2.
AC68U/AC66U_B1 with stock Asus firmware 3.0.0.4_386_43129 and Merlin 386.3_2.

Screenshot 2021-09-09 220005.png


Screenshot 2021-09-09 220024.png


Screenshot 2021-09-09 220054.png
 
Last edited:
I only see one speed test result shared here. Assuming it was a similar outcome with both firmwares. And you took the test from a device behind the AC68U ?
Yes similar result with both Merlin and Stock.

Yes wired to the LAN port of AC68U.

I don't always get close to 500mbps though. Usually sways around 300++mbps. Typical of WiFi, subjected to interference and etc.

Definitely not as low as you mentioned 60-150mbps.
 
I plugged in my portable harddrive to the USB port to use as network drive and I couldn't get speeds above 200mbps.

As soon as I unplugged the external hdd, speeds went back up to above 300mbps.

Do you have anything plugged to both your main router and media bridge?
 
@fisherman10 As best I can tell from your posts is that the AC66u b1 is a media bridge. How is the AC68u configured, the same?

I would still be happy with a 200mbps speed.

Please see my post #18 for a tool to measure you speed internally. This will allow you to specifically test your wireless independent of your ISP. If you get 300 down, I suspect that the 100 up is not the limit of your router.

What if any changes to wireless configuration have you made from default on each device, as applicable, to achieve these speeds.
 
@fisherman10 As best I can tell from your posts is that the AC66u b1 is a media bridge. How is the AC68u configured, the same?

I would still be happy with a 200mbps speed.

Please see my post #18 for a tool to measure you speed internally. This will allow you to specifically test your wireless independent of your ISP. If you get 300 down, I suspect that the 100 up is not the limit of your router.

What if any changes to wireless configuration have you made from default on each device, as applicable, to achieve these speeds.

Both AC66U_B1 and AC68 are configured the same. Both as media bridge. On a good day, I get almost close to 500mbps down. Normally with interference, I get 300++ down.

100mbps UP is my ISP limit. I mentioned earlier that my line is 500mbps down / 100mbps up.


In media bridge mode, there's no wireless configurations to be made. I have tested both stock and Merlin firmwares for the media bridge AND main AX86U router. To add on, I also tried FreshTomato on the AC66U_B1 and AC68U. I get similar performance to stock and merlin when used as Media Bridge.

The link rate stated on the Media Bridge sways from 800++mbps to 1300mbps. Rarely stays on 1300 for long. Too much interference from neighbours and full brick wall and concrete house.


Here are my wireless settings in the main AX86U router. They are mainly stock. Not much changes.
Screenshot 2021-09-13 233156.png

Screenshot 2021-09-13 233220.png
 
Last edited:
Have you fixed your issue with AC68? The only way I was able to over come it is to use John's fork firmware. I saw somewhere that there is an older version from Merlin but I can't find what that version is.
If somebody knows, please post it.

Thanks
 
Stop using dual band router as a repeater or media bridge, these routers are not meant for best performance connecting it wirelessly.

If you can't hardwire the connection to the main router use a Wifi Extender and then hardwire that 2nd router to the extender. This will give you speeds close to 600 mbps, I've tested it.

You are facing the Retransmission issue.
 
Stop using dual band router as a repeater or media bridge

Media Bridge is a client, wireless to wired clients. There is no retransmission issue.
 
Stop using dual band router as a repeater or media bridge, these routers are not meant for best performance connecting it wirelessly.

If you can't hardwire the connection to the main router use a Wifi Extender and then hardwire that 2nd router to the extender. This will give you speeds close to 600 mbps, I've tested it.

You are facing the Retransmission issue.
I don't think you understand what the problem is. There is nothing wrong with my setup. It is a firmware issue. I get full speed with John's fork but I prefer to have Merlin's firmware. There is no retransmission in my setup.
 
I have the same problem and I finally found the issue, Protected Management Frames is causing the performance issue on AC68u.

Once it is turn off, the transmission speed go back to maximum.
 
I have the same problem and I finally found the issue, Protected Management Frames is causing the performance issue on AC68u.

Once it is turn off, the transmission speed go back to maximum.
Where are you turning this off? On the rt configured in media bridge mode?

I'm using a rt-ac68u in media bridge mode to a EAP670.

All testing below done using iperf3 on local lan with server running on a wired gigabit connection.

With the latest (as of 20231209) asus merlin firmware, speeds don't top out over 300 mbps, similar as in this thread. With freshtomato, ~550-600 down, and 500 mbps up. These speeds are not really impressive for a 3x3 connection. Using an ax200 client (2x2 streams) in AC mode and forcing ap to 80 mhz, I get similar speeds.

Edit; flashing john's fork from 8/2022 (https://onedrive.live.com/?authkey=!ALJXk06IprzMMDc&id=9332FC159A7E129!6610&cid=09332FC159A7E129), improved speeds even better than tomato. Reaching ~800 mbps down and 500 mbps up now. Had to dick around with cfe to get dfs channels to work as the EAP above is configured for ch. 100. Doesn't really matter what fw is on here as this box is used in the basement to get a connection when DUT doesn't have wifi connectivity.

With john's fork firmware. Target is an iperf3 server bound to gigabit nic. This is about as good as it gets - ~800mbps +- on the download.
1702237697975.png

For sh!ts and giggles, here's an ax router (netgear rax80) in bridge mode. Testing off the same iperf server as above. AP indicates sync speed of 2100 mbps. I suppose I could also test with iperf server bound to 2.5gb nic, and multiple 1gbit wired clients on the rax80. This is good enough for my needs.
1702237781763.png
 
Last edited:
@RMerlin Any thoughts on why the newer fw (ie 386.12_4) is seeing a slow down when in media bridge mode compared to older fw's?
It's wifi, so a dozen of things can have an impact on performance: the client itself, the environment, any settings that might have been changed on either end, and so on. You will need to troubleshoot it the same way you would troubleshoot any typical wifi client issues.
 
The other end is an AP (tplink eap670 to be exact). No changes were made to any settings on it. The only difference with the asus unit was flashing different firmware (either freshtomaro or john's fw). From a factory reset state, the asus unit is put into media bridge mode where the only settings are the AP connecting to and password.

Asus RT physical location, antenna angle, etc, all the same. Asus device indicates proper channel number and width (80mhz). I can tell on the opposite end all 3 streams are in used based on the sync speed (1300 mbps).

I realize media bridge mode is probably not commonly used these days with all the mesh arrangements, so it's unclear where the deviation in performance started.
 
Someone reported switching WPA2 only to WPA/WPA2 security on the parent AP miraculously fixed the Media Bridge performance. Not recommended from Wi-Fi security stand point, but you can test if this is the case with your setup as well. There are some firmware quirks with this router.

 

Latest threads

Sign Up For SNBForums Daily Digest

Get an update of what's new every day delivered to your mailbox. Sign up here!
Top