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Topic: TL-WR1043ND 802.11n Throughput

The content of this topic has been archived on 26 Apr 2018. There are no obvious gaps in this topic, but there may still be some posts missing at the end.

I have a TL-WR1043ND router flashed with OpenWrt Backfire (10.03.1-RC5, r26686) and the wireless throughput averages around 9 MB/s, roughly half of what I was seeing with the stock firmware (19 MB/s).  I have channel bonding enabled and "iw dev wlan0 link" on the client (Linux with Intel 5300) shows it has a 40MHz connection though the "tx bitrate" varies between 150 and 300 Mbps.  I also set the channel to the same channel that the stock firmware was using.

Both configurations were set wiith the defaults except for encryption being enabled in both and "htmode" being set to "HT40-" with OpenWrt.  Channel 9 was used in both cases.  I also tested with 10.03.1-RC4 and saw the same slower speeds.  The contents of my /etc/config/wireless file is shown below.

How can I enable the full wireless throughput on this router?

config wifi-device  radio0
        option type     mac80211
        option channel  9
        option macaddr  12:34:56:12:34:56
        option hwmode   11ng
        option htmode   HT40-
        list ht_capab   SHORT-GI-40
        list ht_capab   DSSS_CCK-40
        # REMOVE THIS LINE TO ENABLE WIFI:
        option disabled 0

config wifi-iface
        option device   radio0
        option network  lan
        option mode     ap
        option ssid     OpenWrt
        option 'encryption' 'psk2'
        option 'key' 'asdfasdf'

As an update to this I tested it with the latest snapshot of trunk and the behavior was the same.

I'm not sure if it's limited to trunk but at times the throughput seems drop down close to modem speeds.  The following was a test with iperf to a client that's 4 feet away.

root@OpenWrt:~# iperf -c 1.2.3.4
------------------------------------------------------------
Client connecting to 1.2.3.4, TCP port 5001
TCP window size: 16.0 KByte (default)
------------------------------------------------------------
[  3] local 1.2.3.5 port 44545 connected with 1.2.3.4 port 5001
[ ID] Interval       Transfer     Bandwidth
[  3]  0.0-19.5 sec   256 KBytes   108 Kbits/sec

And during this run the following was shown:

root@OpenWrt:~# iw dev wlan0 station dump
Station a:b:c:d:e:f (on wlan0)
        inactive time:  0 ms
        rx bytes:       299670800
        rx packets:     204092
        tx bytes:       15104389
        tx packets:     108808
        tx retries:     33124
        tx failed:      2956
        signal:         -28 dBm
        signal avg:     -28 dBm
        tx bitrate:     6.5 MBit/s MCS 0
        rx bitrate:     270.0 MBit/s MCS 15 40Mhz

Not sure about your numbers, but my 1043 has performance issues in n mode, too.

Using Samba/CIFS, the original firmware can pull about 12 MiB/s using an AR9xxx Windows laptop, and about 11 MiB/s using a AR5416 PCI card under Windows.
RC4 only gets up to about 7 MiB/s with the same laptop, and 5-6 MiB/s using a Ralink 3062 PCI card under Linux.

AFAICT 12 MiB/s is pretty much the limit with 2-stream hardware, so signal should not be a problem here (I did test with iperf too, but the numbers weren't as easy to remember)

I suspect this is all ath9k's fault [insert boatload of expletives for Atheros here], but you might want to ask on this one or IRC,

This is my iperf report on 1043ND

BusyBox v1.15.3 (2011-12-21 21:31:33 WIT) built-in shell (ash)
Enter 'help' for a list of built-in commands.

  _______                     ________        __
 |       |.-----.-----.-----.|  |  |  |.----.|  |_
 |   -   ||  _  |  -__|     ||  |  |  ||   _||   _|
 |_______||   __|_____|__|__||________||__|  |____|
          |__| W I R E L E S S   F R E E D O M
 Backfire (10.03.1, r29578) ------------------------
  * 1/3 shot Kahlua    In a shot glass, layer Kahlua
  * 1/3 shot Bailey's  on the bottom, then Bailey's,
  * 1/3 shot Vodka     then Vodka.
 ---------------------------------------------------
root@OpenWrt:~# iperf -c 192.168.1.116
------------------------------------------------------------
Client connecting to 192.168.1.116, TCP port 5001
TCP window size: 16.0 KByte (default)
------------------------------------------------------------
[  3] local 192.168.1.1 port 36122 connected with 192.168.1.116 port 5001
[ ID] Interval       Transfer     Bandwidth
[  3]  0.0-10.1 sec  24.0 MBytes  20.0 Mbits/sec

wireless config

config wifi-device  radio0
        option type     mac80211
        option channel  auto
        option macaddr  f8:d1:11:24:ab:1a
        option hwmode   11ng
        option htmode   HT20
        list ht_capab   SHORT-GI-40
        list ht_capab   DSSS_CCK-40
        option txpower  18
        # REMOVE THIS LINE TO ENABLE WIFI:
        option disabled 0

config wifi-iface
        option device   radio0
        option network  lan
        option mode     ap
        option ssid     OpenWrt
        option encryption       psk-mixed
        option key      12345678

Use PSK2 for 11n, and try fixed channels. Consider using HT40+/- (option noscan 1 to enforce) for maximum throughput.

The numbers from RC3/RC4 were already obtained by using all of the settings recommended by jow. I still haven't done formal testing with RC6 but I'm not optimistic. If I find some time later today I'll try to post an update.

(Last edited by Frex on 22 Dec 2011, 22:21)

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