Sticky Clients

Nearby Office Complex with bad Wi-Fi


This past week, I was called on to help in a Wi-Fi nightmare at a nearby office complex here in Tennessee.

The issue was client devices having really poor throughput even though the building had a really good internet service.

After a few minutes onsite, I found there were no interferences anywhere in the building so I fired up my survey tools and performed a validation survey.

Contrary to my first thoughts, the survey was darn near perfect in every location and overlapping cells were textbook.

I decided that I would quickly replicate the issue before going forward. The layout is a 2 story building with a lot of open cubicle space and several walled offices.

I carried my laptop, iPad, and iPhone through the front entrance as if I were coming in for work. I went up the stairs and across the floor to the opposite end of the building and sat down at a vacant desk.

upon looking at my devices, I saw I was connected on every device but my iPad and iPhone had really slow connectivity and my laptop (which I just turned on) had great connectivity.

At this point, I began tracking the connectivity back to the actual access points each device was connected to and found that the iPad and iPhone was connected to the access point in the main lobby, while the laptop was connected to the  access point 20 feet from the desk I was sitting at.

This small amount of troubleshooting took me right to the IT Coordinator's office and I asked him to see his WLC.

He logged me into it and let me cruise through the configurations and I found that all the data rates were on, no rf profiles were applied to any of the SSID's and no limits were set to limit connections to each access point.

It was an office complex with just under 60 employees and 9 access points throughout the facility but when I checked connections 28 devices were connected to the lobby access point on 2.4 GHz at -77 dB or worse while 17 more devices were connected to access point in front of the elevator on the first floor at -76 or worse on 2.4 GHz. 13 more devices were connected to the lobby access point on the 5 GHz radio at -79dB or worse.

It became very evident at this point what the issue was.

I spent about an hour looking for devices that had to use 2.4 GHz  and found there were actually none that had to use it so I turned it off for testing.

I set rf profiles making 18MBs the lowest data rate available.

I set the maximum clients per AP to 15.

Once all of these settings were changed, I carried my devices out of the building, rebooted them and went into the building again.... but this time with everything on and operating.

I stopped in the lobby to be certain everything connected and they did, so I went on to the elevator and pressed the call button. My laptop switched to the elevator AP while the Apple devices stayed connected to the lobby AP until I stepped into the elevator.

Once I was in the elevator, the Apple devices switched to the break room AP which was a few feet down the hall from the elevator on the second floor.

When the elevator doors opened, my laptop switched to the 2nd floor office AP in the opposite direction of the break room.

I walked toward the cubicles and the Apple devices switched to the 2nd floor office AP with the laptop.

As I got to the far end of the building where I had sat before my laptop was on the AP 20 feet from the desk and the Apple devices were on an AP between the 2nd floor office AP and the one my laptop was on.

None of them ever roamed to 2.4 GHz but all three devices roamed to a closer AP for better data rates as I traveled through the office.

Since all of the access points rebooted when the profiles were applied, I went around and checked with employees to see how their wireless was working now. Everyone said it was much better than before.

I told the IT Coordinator to check with them all in the morning when they came in and made the walk through the lobby to their desks.

GOOD NEWS!!! Every device roamed as it was supposed to and Wi-Fi was popular again!


Use your RF Tools, adjustments, and profiles.... They Work Great!!!


Brett Hill, CWNE #147