WiFi on RT-AC68U unuseable :mad:

[Michl]

Hello

I has used the last 10 years a cheap Linksys WRT54G with DD-WRT. I had never problems!

Now, I changed my router to a expensive RT-AC68U. But there's a unstable Wifi!?

My configuration:
-----------------
- Both (2,4GHz and 5GHz) Wifi are activated and have different SSID
- I tried, stock firmware, merlin and dd-wrt
- Router in same root

My devices:
-----------
- DELL M3800
- Toshiba Qosmio 500 R13
- Apple iPad 2
- Samsung Galaxy S2+S3
- (Old) VoIP DECT Siemens Gigaset SL75 WLAN

Tried firmwares (latest):
-----------------------
- Stock
- ASUSWRT-Merlin
- DD-WRT

First problem: WPS
------------------
After installation of my RT-AC68U and setup, firstable my old VoIP DECT can't connect no more. After trial and error I identify the WPS-Feature. If it is activated, then my DECT can't subscribe into Wifi!? I don't know why this feature can affect this device!? (but the SSID it can see). After I deactivate this feature, it works now.
But this feature depends only to stock and merlin firmware. In DD-WRT it works immediatelly. But I read about, this feature is default deactivated and not built in because security reasons.


Second problem: Wifi speed
--------------------------
Only in stock und merlin, my DELL computer can conntect with (full?) 844Mbps at 5GHz Wifi. If I using DD-WRT, Windows tells only a connection with 54MBit. Is DD-WRT limited or should this work, too??


Third problem: Reliable Wifi
--------------------------
Strange to say, my DELL has a stable Wifi connection and the (old!) DECT, too. But my other devices seems to works only shortly after reset. If any.
Normally, devices can't connect to any of Wifi or do a connection, but can't transfer data.
But I observe this only at stock and merlin firmware. DD-WRT seems to work, but there I only have 54Mbps.
For instance: my Galaxy S3 needs very long to get a dynamic IP or I see the message "Your internet connection is unstable".


Please help. What can I do still try or check.
I be on the verge of using/reactivate my old rooter again!
I thought ASUS RT-AC68U is one of the best (or at least: fastest) routers!???

Thanks

 

[chris.at]

Hi Michl,

try if it works when you set "Enable WMM APSD" to "disabled" on both frequency bands at wireless/professional setup. Also check if you have the latest wifi drivers installed (of course not on the phone, but on the other computers). Normally with disabled APSD the problems are gone.

chris

 

[staticfree]

If you have your wifi settings set to "Auto" for channel selection, then turn it off and select a channel manually for each band (for 2.4Ghz, 5Ghz).
For the 2.4Ghz band set the bandwidth to only 20Mhz and try channel 6 first.
For the 5Ghz band set it to use 80Mhz bandwidth and select a channel manually (like ch 153) and see how your wifi devices connect. Try and find a channel where your devices work in your environment. See if that help resolve your issues. Most of the time it will.

 

[Michl]

Thank you for your suggestions, but nothing solves my problem.
I think this is a bug in stock firmware and even merlin. I installed now DD-WRT again and this works.

As you can see in logs, client (eg. 192.168.2.51 - smartphone) will not be registered in network. Router does not acceppt incomming requests at 2,4GHz network after some minutes.

DHCP-Nutzungen:
Hostname IP Address MAC Address Expires
DELL 192.168.2.2 e8:2a:ea:90:f5:42 23:59:01 DELL Precision M3800
Michaels-iPad 192.168.2.37 40:30:04:24:31:62 23:58:38 iPad2
OPWL20001E3687446 192.168.2.4 00:01:e3:68:74:46 23:58:29 VoIP-DECT
android-b4403e2f96d35731 192.168.2.51 90:18:7c:d2:6a:85 23:58:11 Galaxy S3 mit Stock-Firmware

Verbindungen:

Android: - WLAN aus -

Proto NATed Address Destination Address State
tcp 192.168.2.37:61895 17.130.254.34:5223 ESTABLISHED
tcp 192.168.2.37:61896 193.149.80.67:443 ESTABLISHED
udp 192.168.2.4:5060 217.10.79.9:5060 ASSURED
udp 192.168.2.2:51944 192.168.1.16:161 UNREPLIED
udp 192.168.2.2:51944 192.168.1.10:161 UNREPLIED

Android: - WLAN ein -
tcp 192.168.2.37:61895 17.130.254.34:5223 ESTABLISHED
tcp 192.168.2.2:65119 173.194.39.1:443 ESTABLISHED
tcp 192.168.2.37:61896 193.149.80.67:443 ESTABLISHED
tcp 192.168.2.37:61903 213.199.179.157:40033 ESTABLISHED
tcp 192.168.2.2:65120 173.194.39.5:443 ESTABLISHED
tcp 192.168.2.37:61904 91.190.216.81:80 TIME_WAIT
udp 192.168.2.4:5060 217.10.79.9:5060 ASSURED
udp 192.168.2.2:51944 192.168.1.10:161 UNREPLIED
udp 192.168.2.2:51944 192.168.1.16:161 UNREPLIED

Android: - IP wird abgerufen -
tcp 192.168.2.37:61895 17.130.254.34:5223 ESTABLISHED
tcp 192.168.2.37:61896 193.149.80.67:443 ESTABLISHED
tcp 192.168.2.37:61903 213.199.179.157:40033 ESTABLISHED
tcp 192.168.2.37:61904 91.190.216.81:80 TIME_WAIT
udp 192.168.2.4:5060 217.10.79.9:5060 ASSURED
udp 192.168.2.2:51944 192.168.1.16:161 UNREPLIED
udp 192.168.2.2:51944 192.168.1.10:161 UNREPLIED

Android: - Verbinden -
tcp 192.168.2.37:61895 17.130.254.34:5223 ESTABLISHED
tcp 192.168.2.37:61896 193.149.80.67:443 ESTABLISHED
tcp 192.168.2.37:61903 213.199.179.157:40033 ESTABLISHED
udp 192.168.2.4:5060 217.10.79.9:5060 ASSURED

Android: - Verbindung mit 5G -
tcp 192.168.2.51:56647 173.194.65.188:5228 CLOSE
tcp 192.168.2.51:40565 173.194.65.188:443 ESTABLISHED
tcp 192.168.2.37:61895 17.130.254.34:5223 ESTABLISHED
tcp 192.168.2.51:41406 54.195.251.62:5223 ESTABLISHED
tcp 192.168.2.51:34734 31.13.100.11:443 ESTABLISHED
tcp 192.168.2.51:39717 173.194.39.6:443 ESTABLISHED
tcp 192.168.2.51:49200 31.13.100.11:443 ESTABLISHED
tcp 192.168.2.37:61896 193.149.80.67:443 ESTABLISHED
tcp 192.168.2.51:53714 31.13.93.5:443 ESTABLISHED
tcp 192.168.2.37:61903 213.199.179.157:40033 ESTABLISHED
tcp 192.168.2.51:54578 173.194.39.6:80 ESTABLISHED
tcp 192.168.2.51:40730 173.194.39.6:80 ESTABLISHED
tcp 192.168.2.51:38293 173.194.39.1:80 TIME_WAIT
tcp 192.168.2.51:38382 173.194.39.6:443 TIME_WAIT
udp 192.168.2.4:5060 217.10.79.9:5060 ASSURED


Wireless-Protokoll:
SSID: "Michl24"
RSSI: 0 dBm SNR: 0 dB noise: -92 dBm Channel: 1
BSSID: 38:2C:4A:4B8:F0 Capability: ESS ShortSlot
Supported Rates: [ 1(b) 2(b) 5.5(b) 6 9 11(b) 12 18 24 36 48 54 ]
VHT Capable:
Chanspec: 2.4GHz channel 1 20MHz (0x1001)
Primary channel: 1
HT Capabilities:
Supported MCS : [ 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21
22 23 ]
VHT Capabilities:
Supported VHT (tx) Rates:
NSS: 1 MCS: 0-9
NSS: 2 MCS: 0-9
NSS: 3 MCS: 0-9
Supported VHT (rx) Rates:
NSS: 1 MCS: 0-9
NSS: 2 MCS: 0-9
NSS: 3 MCS: 0-9

Mode : AP Only

Stations List
MAC Associated Authorized RSSI PSM SGI STBC Tx rate Rx rate Connect
Time
00:01:E3:68:74:46 Yes Yes -32dBm Yes No No 1M 54M 00:21:11

SSID: "Michl5"
RSSI: 0 dBm SNR: 0 dB noise: -92 dBm Channel: 36/80
BSSID: 38:2C:4A:4B8:F4 Capability: ESS
Supported Rates: [ 6(b) 9 12(b) 18 24(b) 36 48 54 ]
VHT Capable:
Chanspec: 5GHz channel 42 80MHz (0xe02a)
Primary channel: 36
HT Capabilities:
Supported MCS : [ 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21
22 23 ]
VHT Capabilities:
Supported VHT (tx) Rates:
NSS: 1 MCS: 0-9
NSS: 2 MCS: 0-9
NSS: 3 MCS: 0-9
Supported VHT (rx) Rates:
NSS: 1 MCS: 0-9
NSS: 2 MCS: 0-9
NSS: 3 MCS: 0-9

Mode : AP Only

Stations List
MAC Associated Authorized RSSI PSM SGI STBC Tx rate Rx rate Connect
Time
90:18:7C2:6A:85 Yes Yes -45dBm No Yes No 108M 150M 00:02:27
E8:2A:EA:90:F5:42 Yes Yes -52dBm No Yes Yes 526.5M 866.7M 00:20:42
40:30:04:24:31:62 Yes Yes -62dBm Yes No No 65M 65M 00:21:01


But I'm annoyed about the ASUS support. There only people who question catalog questions. Typical first level support.
I have suggested that a technician or programmer looks at the problem in a remote maintenance, but apparently there is no third level support at ASUS.
Perhaps Merlin programmers are more interessted to improve stock firmware.

 

[Michl]

Now, I solved the network speed in DD-WRT, too.
I found the solution in thread
http://www.dd-wrt.com/phpBB2/viewtopic.php?p=784904

Network Mode: Mixed
Wireless Channel: 132 (or anything in the 100s) - this is crucial for the higher data rates
Channel Width: 80 Mhz

My data rate is now 866,7 Mbps as in stock firmware, too.

Now, you can chage it back to default (auto) values.

 

[Michl]

But my connection problems remain.
Further discussion: http://www.snbforums.com/threads/2-4ghz-wifi-unstable.23228/

 

[Dr Tone]

Is your 2.4ghz set to 20MHz only? Give it a try if it isn't.

 

[joegreat]

But my connection problems remain.
Further discussion: http://www.snbforums.com/threads/2-4ghz-wifi-unstable.23228/

Hi Michl,

Did you do a factory reset of the router AND remove the profiles from the devices?
Configure the absolut minimum (e.g. WLAN SSID and password only) and test.
If things work then add/change the other features one by one and test each change!

My N68U router runs rock solid WLAN since I got it 2 years ago!
But I did regular factory resets (when driver or default settings changed) to avoid problems.

With kind regards
Joe