430AP wireless performance significantly reduced when controlled by 760controller

[Moop]

Hi! We have an enviroment of about 30 430APs with a 760 MSM controller ( software 6.4.0.0-16925). 

Users are complaining about performance so we started to do some tests.

We took one 430AP and created a regular WPA2-PSK VSC for just that AP and meassured performance (download speed). When we took that same AP and made it autonomous, performance almost doubled!

The VSC created on the controller and the autonomous AP were exactly the same with the only difference being that the autonomous AP had "Severe interference detection/mitigation" ticked in  under radio and the controlled one did not.

The distance between the AP and PC were exactly the same, on the same subnet and took the same route out to the internet.

What could be causing this?

[Davy Priem]

I would start with updating to 6.4.1 release on August 14th. Version 6.4.0 is not the best firmware available.

[Z273]

Hi,

Sorry to hear about bad performance on MSM430.

If you could disclose the config of the test you did, that will give more hint to what went wrong.

Mostly the channel used and the txpower, client device used, your radio is it HT20 or Auto/HT40 mode.

The Severe Interference tick is useful only if your channel is under high interference, the code will try to switch channel to mitigate/avoid the interference, I don't think this is your case.

When you do the perf test, you can look the wireless rate being used i.e. tx/rx to/from client AP from the wireless->overview->mac-of-client page, looking at the rate tx/rx by the AP gives you a hint on the quality of the wifi rates.

If you are in 2.4Ghz, there is a chance the radio will not be able to use HT40, HT40 rate will double the speed when comparing to HT20 in 802.11n.  The radio will backtrack from HT40 to HT20 if the secondary channel is busy, which is the case if your 2.4ghz band is crowded.

More ever, if you can use the MSM430 and put the radio in monitor mode to capture the wifi traffic while you run the test, it will be super useful to troubleshoot what is going on over the air.

Cheers. 

[Niko-Lizard]

Hi.

We are having issues with our MSM430 all over this organization. Very bad performance on download but upload is fine. Running FW 6.5.0.1-19720. Speed test on WiFi shows download speed at 0.3 Mbps and upload speed at 22.6 Mbps. Connection speed is swinging up and down on a client. Does anyone else experience this?

Kind regards.

[Z273]

Hi,

This is bad when I see this "Speed test on WiFi shows download speed at 0.3 Mbps and upload speed at 22.6 Mbps."

Can you disclose more details from your config: channel used, txpower, QOS setting,  client devices laptop/tablet (chipset intel,atheros...).

Also when you run speedtest, can you look at the client rates statistics in the MSM web page to see if you achieve HT MCS rates or only doing legacy rate for down and up traffic.

Do you run iperf or speedtest app?

Usually when the performance is bad, either your devices or AP are not doing frame aggregation, or the RF is really bad, you can see if RF is bad if noisefloor is high because of interference.  Usually more interference in 2.4ghz than 5ghz.

I'm willing to help you troubleshoot is you provide the info asked.

Cheers.

[Niko-Lizard]

Hi

This client is HP Folio 13-2000. Whit build-in Intel Centrino N-1030 Wi-Fi adaptor. It can only run at 2.4GHz running newest Intel driver at the laptop. No QOS setting. Rest of info should be in the screen dumps. Please ask if you need more. We have only MSM430 access points and are running on two MSM760 controllers in a team at FW 6.5.0.1-19720.

Kind regards.

[Z273]

Hi,

The picture that strikes me the most is the ClientStat you sent!

All the rates are not very good, very few attempt to do even the MCS 802.11n rate, most of the rates are legacy b/g, yike!

The signal level seen by the AP seem to be good, noise level a bit high but I don't think that is the problem here.

I look at the RadioMap and your txpower is at near max, and the AP is seeing like 42 neighbooring AP, nothing alarming here.

The wifi card intel N-1030 kind of "suck" because it is single band only, why on earth people still put single band radio, except to cut the cost.  That N-1030 is like the old intel5100, it has 1 transmit but 2 receives, so the card transmit 1-stream of traffic MCS0..7, while it is capable to receive up to 2 streams, i.e. up to MCS15.  It also has builtin bluetooth.  Intel disguise very well the 1x2 cripple 1 tx, because most of the people I spoke are unaware of the 1tx-2rx thing 8-)

I notice on the ClientStat the device is in powersave state, can you run a test where you force the laptop to more aggressive power usage and plug it in the AC to avoid the laptop entering powersave mode, usually the setting is Power Plan under Win7.

Another info you can disclose is the wireless driver version, Intel has a major bug in the powersave, just google 'intel uapds problem' and you will get more details.

Do you have another laptop with a better wifi card from intel like the intel5300/intel6300 to test, and the screen of the wifi rate is super useful!!

[Niko-Lizard]

Hi

Most employee laptops are HP Folio 13.2000 with the Intel N-1030 Wi-Fi adaptor. Driver used v. 15.11.0.7 and the one predefined by windows 8.1. These screen dumps are from a surface. Have three of them right here one my table, none of them is able to connect Wi-Fi.

Just downgraded firmware to 6.4.0.0-16925 and is using configuration from the last time we were running this version. However, I did not make any different.

Kind regards.

[Z273]

Hi Niko-Lizard,

I notice a slight but fundamental difference in the radio config you have for 6.5.x versus 6.4.x .

For radio2 2.4Ghz, I notice the radio 2.4 Wireless Mode is "b/g" when you use 6.4.x, in 6.5.x  the radio2 mode is "n/b/g".

You must set it to "n/b/g", otherwise you don't have the 802.11n rates, only the legacy b/g rates, not sure that you want that as all your client devices are 802.11n capable

You said earlier most of the laptops are using intel single band radio card in 2.4ghz, it means you are not doing any 802.11n.

I only see most of devices in the screen shoot you sent are dualband because they are connected to the radio1 5ghz, and I do see this radio is doing 802.11n rates, also because the radio1 setting is "a/n" which is the correct setting if you want 802.11n support.

There must be a reason why you have set radio2 setting to "b/g" instead of "n/b/g", but I don't recommand that setting as no 802.11n.

Regards.

[Niko-Lizard]

Hi Z273

It is just a little bug in my loaded configuration I will change it right away. However, it does not matter in the 5GHz example here or am I wrong?

Kind Regards