WiFi is like the old phone party line. Only one thing can talk at one time so it will slow with each device that connects. As Chromebooks are very chatty the speed loss will be felt. Normal machines like iPads and notebooks cache content and will be less of a load.
By design, this all seems proper. Chromebooks will soak the WiFi and internet link.
I work for a small school who recently did some hardware upgrades but does not have the budget for an IT guy so I am helping out without much of a background in IT.
My problem is my network drastically slows down when about 20 chromebooks connect to an AP. It is to the point where the chromebooks even have trouble logging in or accessing a basic web page. When traffic is light on a typical laptop or iPad it usually runs at 80ish mb/sec for both upload and download.
What is the best way to troubleshoot where my problem is?
I am running:
12 - TP-link EAP120 access points in cluster mode leading to
3 - gigabit switches placed 1 per area connecting roughly 5 APs each leading to
A gigabit switch in the server room
The server
The firewall
The fibre Internet connection.
Other info: The server is a HP ProLiant ML350 G5 running Windows server 2003. All cabling is cat5e.
Side Note from recent test: I ran 20 chromebooks all at the same time running YouTube. The last couple started struggling to load pages or login. At that peak I checked the AP they were connected to and it was at 4% cpu and 51% for the ram. So I think the APs are fine and the problem lies elsewhere but I don't know where to go from here.

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