1815i and Microsoft Surface VERY VERY slow

[SonusFaber]

It is a fresh installed Microsoft Surface Pro running Windows 10 connected to Cisco 1815i running the latest versione of Mobility Express.

Download speed is slow... VERY slow... terribly slow: less than 1 Mbps in most cases

Upload speed is good: 50+ Mbps

I turned on an old AP in the same position where there is the 1815i (a no name \ no brand AP) and everything is good.

I have tons of other devices and thay run very well, so just the Surface is suffering and just with Cisco AP

Any idea?

[Scott Fella]

Slow, even with an open ssid? Start with a very basic open ssid with no added features enabled.

[SonusFaber]

I investigated a bit more.

The Surface is capable of both 2.4 and 5 GHz.

With the Cisco the Surface negotiates 2.4 GHz and the performances are very poor in download

With another old AP it negotiate 5 GHz and performances are very good.

Unfortunately the Marvell drivers of the Surface do not let me prefer one band versus another, so I configured the Cisco to use only 5 Ghz and so the Surface negotiate 5 GHz.

Anyway, performances are very poor with the Cisco only at 2.4 GHz, even using the same channel that works perfectly on the ther AP (of course, not both turned on at same time).

Strange.

I follwed your suggestion and it happens also if the WLAN is open. I setup a test SSID following the wizard and accepting the defeults.

[Leo Laohoo]

What happens if the AP only broadcasting in 5.0 Ghz?

[Scott Fella]

You solved your own question. 2.4ghz these days are over utilized since there are only three channels to choose from. 5ghz is the one you should be using and if all your devices can use 5ghz, disable 2.4ghz. You also need to understand that the devices are the one that chooses what ap and what band it prefers. Try setting the power on the 2.4ghz low and making sure the power on the 5ghz is high. This way devices will choose the 5ghz. You also have to have enough density since 5ghz will attenuate more than 2.4ghz.

[SonusFaber]

I know that 2.4 GHz is a lost battle today... too many devices... too many interferers... few channels, etc.

The thing I can not understand is that: two APs, one is the Cisco the other is no brand\no name, both @ 2.4, both on the same channel... with the Cisco the performances are very poor and with the other are very good, moreover very poor with the Cisco just in download, since in upload it is perfect.

With the Cisco I can see in the log that the negotiated speed is 144 Mbps, while the real speed is below 1 Mbps in most cases.

In my building I am the only one using WiFi, others floors are still empty and the nearest building with someone using WiFi is at 50 meters

[Scott Fella]

Use a tool like iperf3 and test. This tool can be used on phones also. This way you have some speed tests in your local lan. Make sure that one device is on wired, that should be the one acting as a server. Then post some results like:

Device1 2.4ghz download
Device1 2.4ghz upload

If I run into any issue like that what you are experiencing, I would upgrade/downgrade the code and or upgrade or downgrade the nic driver. It seems to me unless there is an issue with your network setup, that you probably will not solve this without a code or driver change. Everyone here is going to assume that your wireless and wired setup is not the issue so hopefully you looked into that. You tested with an external usb wireless nic by chance?

[SonusFaber]

thanks.

The measured speed was using iperf and not Internet speedtest.

Anyway I donwgrade the ME software to 8.5.140. Something interesting:

ME 8.10.105

Surface associates @ 2.4 GHz and the download speed is very poor ( 1 Mbps ), while upload is OK

If I force the Surface to use 5 GHz, then it wont connect. Surface says "unable to connect to this network" while Cisco says "invalid data rate" in the client's log

ME 8.5.140

Again Surface associates @2.4 with poor speed like before

But if i force Surface to use 5 GHz, then it connects, speed is PERFECT (almost 100 Mbps) and the Cisco does not report any erros.

About drivers... the Surface's NIC is from Marvell but marvell does not provide directly any drivers.

I can not downgrade or upgrade the NIC drivers because it is the only one available from Microsoft and it is embedded in the Surface's core image.

The fact that with the older ME SW it works at 5 GHz.... strange... I would say there is something wrong with Cisco

Unfortunately these two ME versions are the only ones I have (these are the two loaded on the AP).

I do not have any SmartNet and the TAC does not takes care about me.

[Scott Fella]

I have not used ME in a while, but I can tell you that on those code versions with a WLC, the Surface does not have that issue. We have majority of user with surface and I have two different surface at home with my setup and never had an issue. Seems to either be an issue with the AP itself unless again something with a setting you have defined on the wlan or RF that is causing the issue you have.

[SonusFaber]

I am talking about Surface Pro first versione, the one equipped with the Marvell 350N WiFi card.

Since I am not so expert, the only things that I have customized with these two 1815i (I have two since my house is big) are the user\password, IP address, WLAN name and PSK key.

Everything else is the Cisco default.

Moreover I can understand why so different behaviour with the two software versions of the ME.

I tested at work, where we have Cisco too (but different models) and it works perfectly.

So, can you tell me where I can have a look to investigate?

[Scott Fella]

Code versions fixes bugs and also introduces features. If your settings are the same at work and what you have at home, then maybe the issue is with the AP’s you have. Where you start to troubleshoot is by process of elimination. Your testing should eliminate wired vs wireless, wireless devices vs NIC type and drivers, various wireless device types. 2.4ghz vs 5ghz, 40mhz vs 20mhz channel width on 5ghz, etc. Since you are not able to upgrade the NIC driver, you install an external usb NIC and compare. That helps you further narrow down the root cause.

[patoberli]

Try the latest 8.5.160.0 release, Cisco has fixed various issues on the 2.4 GHz band in that firmware.