Client load balancing between 2.4 and 5, how does it work?

[david_henderson]

Our football field has 4 large light poles and 25 foot up each pole we have hung a T710 outdoor AP. We have an SSID that personal devices connect to and we use both 2.4 and 5GHz for the wlan group. I have measured signal strength sitting in the bleachers and see this:

Band     Channel     Signal Strength (dBm)
  2.4           11                     -56
  2.4           11                     -59
  2.4             6                     -64
  5            157                     -59
  5            149                     -62

The laptop I was using for testing was seeing signal from APs hung on several different light poles. Three questions:

1. When a personal device joins the network, will it join at 2.4 or 5GHz? My guess is it will join at 2.4GHz since it has better signal strength than 5GHz
2. On a Friday night as more people stream into the stands and we have lots of devices joining, will some type of load balancing kick in? In other words if one AP on a light pole has 80, 90, 100 clients connected at 2.4, will other devices start connecting at 5GHz to maximize over the air bandwidth and give everyone a better experience?
3. We use a Virtual Smartzone Controller, are there settings related to load balancing I should check and/or change?

[jamie_walmsley]

will depend totally on the client, the client will have its own criteria for selecting what it will associate to. for instance the following links might help understand how apple devices decide what to associate to and the roaming decissions made

https://support.apple.com/en-us/HT206207
https://support.apple.com/en-gb/HT203068

The Ap's can withhold probe responses in order to try and influence the client to associate to the 5G radio (thats how band balancing works) but essentially its down to the client. the thresolds used for band balancing can be configured on the controller. (On vSZ its on the Ap group settings then advanced)