Wireless Access

Hi,

Does anyone have some info about which wlan chipsets play nice with those MSM APs?
I tested an MSM422 running at pure N 5GHz with a Thinkpad T400s which has a built-in intel wifilink 5300 pcie card.
Wifi settings were set to no powersave, maximum performance.
The Notebook was directly in front of the AP.
Settings in the AP were Pure N 20/40 width, channel auto, internal antennas.

Running iperf from both linux and windows 7 resulted in about 4Mbyte/s to the access point's built-in iperf server.
File transfers to a fileserver connected via 1GBit to the accesspoint also didn't exceed 3MByte/s.
The accesspoint was either directly connected to a hp 1810G-24 using hp's poe injector, or connected to a cisco poe GBE switch.. rates didn't differ at all.


Are there any known limitations and/or speed issues with intel nics especially the wifilink 5300?

Which chipset would you suggest? What about Ralink?


Thanks very much for any info and help

Max

I should probably add that windows displayed the wifi rate as 300mbit/s

Concurrently only you (1 user) connect to that AP?

Yes, only me

Any others wifi channel in your environment? Does latency is good from laptop to AP? Which firmware version you are running currently?

Thanks for your support!

No other networks are using the 5GHz band. The AP is completely lonely ;)

Firmware version is 5.4.0.

I also got a MSM410 running the same firmware..
I'll try it with that one and report back.

Thank you,

Max

This is rather strange.

Here's the iperf log with two different fw's (still had the old 5.3 on that device)

BTW: ping delays are low.

fw: 5.3.1.0-01-7143





bin/iperf.exe -c 192.168.11.2 -P 1 -i 1 -p 5001 -f m -t 1000

------------------------------------------------------------

Client connecting to 192.168.11.2, TCP port 5001

TCP window size: 0.01 MByte (default)

------------------------------------------------------------

[148] local 192.168.11.50 port 49199 connected with 192.168.11.2 port 5001

[ ID] Interval Transfer Bandwidth

[148] 0.0- 1.0 sec 5.95 MBytes 49.9 Mbits/sec

[148] 1.0- 2.0 sec 5.82 MBytes 48.8 Mbits/sec

[148] 2.0- 3.0 sec 4.03 MBytes 33.8 Mbits/sec

[148] 3.0- 4.0 sec 0.00 MBytes 0.00 Mbits/sec

[148] 4.0- 5.0 sec 0.00 MBytes 0.00 Mbits/sec

[148] 5.0- 6.0 sec 0.00 MBytes 0.00 Mbits/sec

[148] 6.0- 7.0 sec 0.00 MBytes 0.00 Mbits/sec

[148] 7.0- 8.0 sec 0.00 MBytes 0.00 Mbits/sec

[148] 8.0- 9.0 sec 0.00 MBytes 0.00 Mbits/sec

[148] 9.0-10.0 sec 0.00 MBytes 0.00 Mbits/sec

[148] 10.0-11.0 sec 5.77 MBytes 48.4 Mbits/sec

[148] 11.0-12.0 sec 5.90 MBytes 49.5 Mbits/sec

Done.



bin/iperf.exe -c 192.168.11.2 -P 1 -i 1 -p 5001 -w 64.0K -f m -t 1000

------------------------------------------------------------

Client connecting to 192.168.11.2, TCP port 5001

TCP window size: 0.06 MByte

------------------------------------------------------------

[148] local 192.168.11.50 port 49200 connected with 192.168.11.2 port 5001

[ ID] Interval Transfer Bandwidth

[148] 0.0- 1.0 sec 6.54 MBytes 54.9 Mbits/sec

[148] 1.0- 2.0 sec 6.43 MBytes 53.9 Mbits/sec

[148] 2.0- 3.0 sec 6.53 MBytes 54.8 Mbits/sec

[148] 3.0- 4.0 sec 6.47 MBytes 54.3 Mbits/sec

[148] 4.0- 5.0 sec 6.55 MBytes 54.9 Mbits/sec

[148] 5.0- 6.0 sec 6.52 MBytes 54.7 Mbits/sec

[148] 6.0- 7.0 sec 6.52 MBytes 54.7 Mbits/sec

[148] 7.0- 8.0 sec 6.47 MBytes 54.3 Mbits/sec

[148] 8.0- 9.0 sec 6.49 MBytes 54.5 Mbits/sec

[148] 9.0-10.0 sec 6.61 MBytes 55.4 Mbits/sec

[148] 10.0-11.0 sec 6.45 MBytes 54.1 Mbits/sec

[148] 11.0-12.0 sec 6.52 MBytes 54.7 Mbits/sec

[148] 12.0-13.0 sec 6.49 MBytes 54.5 Mbits/sec

[148] 13.0-14.0 sec 6.54 MBytes 54.9 Mbits/sec

[148] 14.0-15.0 sec 6.58 MBytes 55.2 Mbits/sec

[148] 15.0-16.0 sec 6.52 MBytes 54.7 Mbits/sec

[148] 16.0-17.0 sec 6.54 MBytes 54.9 Mbits/sec

[148] 17.0-18.0 sec 6.51 MBytes 54.6 Mbits/sec

[148] 18.0-19.0 sec 6.45 MBytes 54.1 Mbits/sec

[148] 19.0-20.0 sec 1.28 MBytes 10.7 Mbits/sec

[ ID] Interval Transfer Bandwidth

[148] 20.0-21.0 sec 0.00 MBytes 0.00 Mbits/sec

[148] 21.0-22.0 sec 0.00 MBytes 0.00 Mbits/sec

[148] 22.0-23.0 sec 0.00 MBytes 0.00 Mbits/sec

[148] 23.0-24.0 sec 0.00 MBytes 0.00 Mbits/sec

[148] 24.0-25.0 sec 0.00 MBytes 0.00 Mbits/sec

[148] 25.0-26.0 sec 0.00 MBytes 0.00 Mbits/sec

[148] 26.0-27.0 sec 2.93 MBytes 24.6 Mbits/sec





fw: 5.4.0.0-01-8027



bin/iperf.exe -c 192.168.11.2 -P 1 -i 2 -p 5001 -w 64.0K -f m -t 1000

------------------------------------------------------------

Client connecting to 192.168.11.2, TCP port 5001

TCP window size: 0.06 MByte

------------------------------------------------------------

[148] local 192.168.11.50 port 49204 connected with 192.168.11.2 port 5001

[ ID] Interval Transfer Bandwidth

[148] 0.0- 2.0 sec 12.9 MBytes 54.0 Mbits/sec

[148] 2.0- 4.0 sec 12.8 MBytes 53.5 Mbits/sec

[148] 4.0- 6.0 sec 12.7 MBytes 53.2 Mbits/sec

[148] 6.0- 8.0 sec 12.8 MBytes 53.7 Mbits/sec

[148] 8.0-10.0 sec 13.0 MBytes 54.7 Mbits/sec

[148] 10.0-12.0 sec 13.0 MBytes 54.4 Mbits/sec

[148] 12.0-14.0 sec 12.8 MBytes 53.5 Mbits/sec

[148] 14.0-16.0 sec 12.9 MBytes 54.1 Mbits/sec

[148] 16.0-18.0 sec 12.7 MBytes 53.1 Mbits/sec

[148] 18.0-20.0 sec 13.0 MBytes 54.6 Mbits/sec

[148] 20.0-22.0 sec 12.9 MBytes 54.1 Mbits/sec

[148] 22.0-24.0 sec 12.8 MBytes 53.8 Mbits/sec

[148] 24.0-26.0 sec 12.9 MBytes 54.2 Mbits/sec

[148] 26.0-28.0 sec 12.4 MBytes 52.1 Mbits/sec

[148] 28.0-30.0 sec 12.8 MBytes 53.7 Mbits/sec

[148] 30.0-32.0 sec 12.9 MBytes 54.0 Mbits/sec







So the rates with the new firmware are stable.
When transferring a file I get 10mbyte/s with this unit, where's I only get 3mb/s with the msm422.

But it's very suspicious that rates in iperf seem to be capped at 54mbit.
This leads me to the assumption that either I configured something wrong in the AP, or that there's a problem with the laptop. But since this happens under linux and windows I don't think that it's very probable.

Do you know some settings in the Accesspoint which could lead to those poor results? I left everything at default except I disabled security filters, enabled wpa psk, set mode to pure N 5Ghz, cahnnel width auto, guard interval short..

I'll test with another notebook tonight.

Thank you!

The results you perform previously is from MSM410 on ver5.4 firmware as well? I can read 3 test you performed.
The i-perf won't cap at 54Mbit. If you try wired connection you should getting near to full speed.
Try to use old firmware version like 5.3.1 it would be stable a bit in term of signal. Besides, try to use a/n instead of pure 'N'. Try to doing the test using the other laptop. Make sure is 5GHz n capable.

Hi, the first (unstable) result was with firmware 5.3.x
The results with 5.4 are stable.

I have N in 5 GHz mode.. Now you want me to test mixed mode N/a did I get you right?

Thnx!

yes..so any update?

Hi,

sorry for the delay.
I tested with a different laptop intel 5100 as opposed to 5300 and got the same results with the AP directly in front.
I then configured the AP to use N/a mode and got the following:

bin/iperf.exe -c 192.168.11.2 -P 1 -i 1 -p 5001 -w 64.0K -l 2.0M -f m -t 10000

------------------------------------------------------------

Client connecting to 192.168.11.2, TCP port 5001

TCP window size: 0.06 MByte

------------------------------------------------------------

[148] local 192.168.11.1 port 49249 connected with 192.168.11.2 port 5001

[ ID] Interval Transfer Bandwidth

[148] 0.0- 1.0 sec 6.00 MBytes 50.3 Mbits/sec

[148] 1.0- 2.0 sec 6.00 MBytes 50.3 Mbits/sec

[148] 2.0- 3.0 sec 6.00 MBytes 50.3 Mbits/sec

[148] 3.0- 4.0 sec 8.00 MBytes 67.1 Mbits/sec

[148] 4.0- 5.0 sec 6.00 MBytes 50.3 Mbits/sec

[148] 5.0- 6.0 sec 6.00 MBytes 50.3 Mbits/sec

[148] 6.0- 7.0 sec 8.00 MBytes 67.1 Mbits/sec

[148] 7.0- 8.0 sec 6.00 MBytes 50.3 Mbits/sec

[148] 8.0- 9.0 sec 6.00 MBytes 50.3 Mbits/sec

[148] 9.0-10.0 sec 6.00 MBytes 50.3 Mbits/sec

[148] 10.0-11.0 sec 8.00 MBytes 67.1 Mbits/sec

[148] 11.0-12.0 sec 6.00 MBytes 50.3 Mbits/sec

[148] 12.0-13.0 sec 6.00 MBytes 50.3 Mbits/sec

[148] 13.0-14.0 sec 8.00 MBytes 67.1 Mbits/sec

[148] 14.0-15.0 sec 6.00 MBytes 50.3 Mbits/sec

[148] 15.0-16.0 sec 6.00 MBytes 50.3 Mbits/sec

[148] 16.0-17.0 sec 6.00 MBytes 50.3 Mbits/sec

Done.




So now there are some spiked to 67.1.

Isn't that very suspicious? Exactly 50mbit.. what misconfiguration could cause that? As stated in my first post I didn't configure anything except I set the Ap to N only in 5GHz, set a wpa psk key and disabled security.

Strange.. also strange that the same things happen with a MSM422 (this is a 410 unit).

I tried unchecking lower rates in the VSC profile. Unchecked everything except MCS 3 and above. But that way the laptop couldn't even detect the AP.


Thanks for any help really, this is driving me nuts!

Dear Max,

couple of notes to check out:
you mentioned powersave (WMM?)
WMM is part of 802.11n, so make sure this is enabled.
Also check an Iperf setting to use more parallel stream (in order to optimize use of the spatial streams inside 802.11n)
I believe it's -P (Capital) 4 to test with 4 streams.

What is your signal strength look like, don't go below -40/-45 dB (SNR below 60/55)
If you have those numbers move away from the radio, too close isn't always giving you better result.
Often is results to over shouting of the radio.

Looking forward to some of your results.

Mike Hydra

Hi Mike,

signal strength is between -20/-30.
running 4 connections simultaneously doesn't change much.
I'll do some more tests and report back with more info.

Thanks for all your help btw!

Dear Mike,

I did a reset to factory defaults and reconfigured the AP.

It's still the same.

There's something interesting in the Radio Info system log though.

These are the numbers when I was doing a longer iperf run:

MAC address -- RX Pkts by MCS --
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
00:21:6A:74:0F:C2 1 0 0 0 8 10 10 8 0 0 0 0 9 30 2282 1029071

MAC address -- TX Pkts by MCS --
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
00:21:6A:74:0F:C2 13 0 0 1 104 125 1302 380122 0 0 0 0 0 0 0 0

I hope the formatting is properly retained, for the case it's not I uploaded a txt.

You can see that the AP is receiving my packets with MCS15 rate, but sending the ACKs with MCS7 only.

The iperf rates as stated in my previous post are the same when doing 4 parallel streams.
In gentoo it's about the same too.

I'll upload the pics for you to check my config settings.

Thank you!

Max

Okay the formatting isn't retained it's quite the chaos, please see the txt file instead.

Here are my settings screencaps.

Hi, looking at the wireless status page there were quite "a few" tx retry frames showing.
I enabled the rts treshold option trying 1540 -> 128.
At 1024 I had about a third less "Tx single retry frames" than with a setting of 512, but with 1024 "Tx multiple retry frames" were about 3 times as much as with 512. The same applies to limit exceeded.
So decreasing the value had a positive effect on multiple retry frames and limit exceeded values, but not for single retry.
However a setting of 512 seems to prevent those 0mbit/s periods with iperf..
Decreasing the value firther had no more positive effects..

Here's a screencap of the status page after running iperf for 30 seconds (stats were reset before) with an rts treshold setting of 512.

BTW: do you have any idea why there are QoS packets stats when I disabled QoS in the VSC settings?

Okay sorry, please forget what I said about the 512 setting preventing periods of no throughput in iperf. They still occur when testing for a longer time, but they don't happen as often as before I think.

BTW: There isn't ANY other AP in the 5GHz band in my area.. using 5GHz on wifi devices is still quite uncommon where i live..

No one any idea?


If someone sees any mistake I probably made in configuring the unit, please tell ;)

Thank you!

Today I'll do tests with a new intel 6100..
If I don't find anything, I'll call support.

I can't believe though that I didn't do any major mistakes, as 3 different Notebooks behave exactly the same.
Another possibility that would seem plausible is that the MSM4xx don't play well with (at least newer) intel wifi wlan cards. But they are SO common.. can't believe this either..

Ok, actually did a Test with a (notoriously bad) Realtek card. Behaved the same except I got even lower rates..

Please ensure you have WPA2-AES, intel5300 requires WPA2-AES to run N speed > 54mbits.

I was able to iperf with at least 90Mbits to MSM422, my vista driver show like you 300mbits.
I think my speed was limited by the iperf serv connected to 100ethernet.

Also when doing your test, don't be so close to the AP.

Z273

Hi,

thank you! I will ensure it's wpa2-aes, which I think it is, but will check again and test the AP at a wider range.

Thanks for all your help! Enabling WMM did it!