Wireless Access

Hello everyone,

Here at my company, we have 2 Aruba switches (1930 48p Gigabit CL4 PoE 4p SFP+ 370W) and 6 Access Points (AP22 Dual Radio 2x2 Wi-Fi 6 for indoor environments).

We are facing a recurring issue: one of the APs is installed in a hallway that serves 6 call center rooms. These rooms have soundproof padding on the walls to reduce external noise, and users inside them frequently complain about unstable Wi-Fi connectivity.

I've already read a bit about Wi-Fi channels, but I would appreciate your advice.
What can I do to improve the connection inside these specific rooms?
Would changing the channel usually help, or would it be better to replace this AP with a more powerful model?

Thank you in advance!

Hi Guilherme

Bad WiFi connections can have many reasons. The first question would be: did it ever work stable? If yes: what did change? This could be firmware upgrades on clients or APs, change in configuration (power settings, channel assignment...). Second question: with "unstable Wi-Fi connectivity" I assume a loss of WiFi connection: in general, you'd have to disable/enable the WiFi NIC or reboot the device in order to get connection again, right?

If the APs signal overlap too much, it may encourage clients to roam between both APs until it loses the connection to the WiFi alltogether. What I also observed in the past: a client roams between the 2.4GHz and 5GHz band - on the same AP - until it loses connection. If not required, disable the 2.4GHz band alltogether. If some clients still require it, create a separate SSID, like "My-Company_24" exclusiv on 2.4GHz band.

About if you need an AP with higher capacity: what kind of traffic is used and how many end devices do connect to the APs? A conservative estimate is, that about 15-30 clients per AP can do decent VoIP calls. If you have more concurrent clients, consider adding more APs or use APs with 4x4 antennas instead.

What you can do: install a WiFi tool on your laptop, like InSSIDer or "NetAnalyzer" on your Android smartphone. You can check signal strength, bands used and channel overlaps.

I hope this helps.

Good morning,

This comes down to Wi-Fi design as much as technology. There are a few things you can do to improve the performance:

• Make sure the slower MBRs are disabled
• Do not have too many SSIDs (I aim for 2, 3 maximum)
• If you can turn off 2.4Ghz do, if you can't then keep it at 20MHz. 5GHz - if you're not too contended on airspace stick with 40MHz channels to encourage clients to use 5GHz over 2.4 without using the network side band steering options as they often cause issues
• Do some surveys even if it's with a free tool on your phone to look at RSSIs and SNRs, understand why it's not working because then you can make an informed decision on the best fix
• Upgrading to bigger, better, faster APs will not fix a design or configuration problem. In some cases going bigger, more powerful will make it worse.
• If there are many clients using the APs or the sound proofing also is good at absorbing RF then you may want to look at using an AP per room

Regards,

Richard

Seconding the advise already provided.

Obtain a copy of the Aruba Utilities on an android device or equivalent -InSSIDer, etc.. as already mentioned. Our objective is to measure the 2.4GHz and 5GHz signal from the AP inside the soundproof rooms. 

https://play.google.com/store/apps/details?id=com.arubanetworks.arubautilities&hl=en-US

Let's say standing under the nearest AP in the hallway, measure the signal from the BSSID.  Let's say it's -50dBM, or around 40 SNR.

Now, move inside the soundproof room, stand at position_A

measure again, note the delta. Let's say it's -60dBm

Now close the door to room_A and repeat the measurement.  this is position_B

Move around the room where people might likely be sitting/standing, this is position_C, repeat the measurement.

Repeat this for 2.4GHz and 5GHz - depending on the soundproofing and shielding (is the room also RF shielded ?

which is quite common for secure conference rooms)

Result is we know the amount of attenuation provided by the room. We'd like a minimum of  approx. -70dBm or around 20SNR at a client device inside the room.

Generally, 2.4GHz may penetrate solid material better than 5GHz, just the physics. 

If either band does provide adequate signal inside the room, one might experiment with channels to see if low or high might provide just a small benefit.

A differing AP model will not likely help.

More TX power may help, channel width should not make much difference.

In some cases, particularly if there is RF shielding - one has to mount the AP inside the room.

That tool looks interesting.  Any good tutorials available, looks like there is a lot going on (on a very small screen)?  Is it supported by Aruba?

These links may be a bit outdated:

https://airheads.hpe.com/discussion/is-there-any-documentation-for-the-aruba-utilities-mobile-app

https://airheads.hpe.com/discussion/aruba-utilities-introductory-video-handover-tab

https://arubanetworking.hpe.com/techdocs/AnalyticsLocationEngine/Content/ArubaFrameStyles/Deploy/Appendix.htm

The basics require only that the android device have the ability to send email - from the Wi-Fi monitoring screen where we see the nearby APs with signal strength - upper right "Email-logs".

I'll find out from the Author where the current code is maintained.

------------------------------
Shawn Adams
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Here is a PDF copy of the 2.7 Documentation version.

Attachment(s)

ArubaUtilities User Guide Rev 2_7.pdf   165 KB 1 version

Hi, I'm the author of Aruba Utilities.

First, this not an HPE Aruba Networking product, it's a project I do on the side.  Some of it works with Aruba-specific APIs, but most of the features are for general Wi-Fi and networking diagnostics.  I try to show all the information the standard Android OS allows.

I confess to keeping less than rigorous paperwork - attached is the last guide I put together, I see it's already a few years old.  But... I'm reachable at ctodeveloper.arubanetworks@gmail.com, and I'll take phone calls or conference calls from anyone who's interested in how it works.  And I welcome suggestions, bug reports and ideas for improvements - please let me know.

Peter Thornycroft, CTO group, HPE Aruba Networking

Attachment(s)

ArubaUtilities Mar 23.pptx   16.99 MB 1 version