Connection instability with certain client devices

[russlench]

Hi guys,

I have a recent installation comprising of 6 APs, all hardwired via a POE switch, distributed around a client property in order to give the best coverage. 4 wireless network are configured, each with different limitations depending on user access.

I've had a few mentions now about certain devices having sketchy connectivity so visited today to perform a few tests.

One of the trouble devices is a Samsung J3 phone, I performed a couple of tests on this device, comparing the results to my phone (iPhone 7).

I found that:

1. Though both devices were right next to each other, within approx. 2m range of AP1, the Samsung phone preferred to connect to an AP that was much further away. It also seemed to display an inconsistent signal strength reading for each of the networks being broadcast from all APs.

2. When both devices were connected to the closest AP, and showing excellent signal strength, running a speed test on the iPhone reported a 5Mbps connection up/down (maximum allowed on this particular network). The Samsung however reported a 0.13/0.33 connection up/down and even timed out on occasion - the speed issue is also confirmed by a very poor browsing experience on this device.These statistics were repeated on each wireless network, including networks that did not have and bandwidth restrictions, again wielding the same poor results for the Samsung device each time.

Questions that I have on this are, could this be a result of older wireless hardware on the Samsung phone? - I've read that the J3 does not have support for 5GHz but surely as the Go APs are broadcasting on both frequencies that there shouldn't be an issue with throughput.

If this is a compatibility issue, is there a feature available to enable legacy connection types like there is on the enterprise Meraki hardware?

Although I only tested with one trouble device, I have been told that the issue is more widespread and on initial questioning only appears to be affecting Android based hardware.

Has anyone else experienced similar, or have any idea what steps to try in order to fix?

Cheers

Russ

[GoJoe]

Hey Russ!

To your first finding, which AP to connect to is a purely client side decision (as are things like when a client decides to roam from one AP to another one). Each client device vendor has their own algorithm taking in a bunch of different factors to determine which is the "best" AP to connect to; the main one being RSSI Threshold (received signal strength). Some client devices have a higher threshold and some a lower one, for what signal level they appropriate before they need to move to a new AP.

For the second one, I think you may have hit the nail on the head. 2.4GHz is very congested (having only 3 "usable" channels for all 2.4Ghz devices). Since WiFi is a shared medium, the client device has to compete with all other 2.4Ghz clients. Other client factors such as how many spatial streams does the client have can come in to play as well. Since the iPhone is able to max out it's connection, it would seem to point towards 2.4Ghz RF congestion being the culprit.

Cheers,

Joe

[russlench]

Hi Joe,

Thanks for the reply!

I take your point on the differences, both with connecting to preferred APs and with congestion. I didn't want to make my first post massively long so (I thought it was long enough already!), what I'd like to try is to completely isolate this issue to determine the possible cause and post the findings.

I've not seen the same kind of behaviour in the enterprise environments I have using MR APs so wondered if this was a GO only issue.

The only wireless networks that are visible are the ones being broadcast by the GO APs (so it's not like there's a bunch of other networks using the airways). What about if I temporarily take offline all APs bar one, setup one unlimited network, connect both devices and test this?

Cheers

Russ