I have a Cisco WAP4410N AP device.
Since yesterday, it is supposed to serve a network of about 15 (max 20) clients at the same time, but not all clients will be using bandwidth simultaneously, since it's a mixed network of notebooks/tablets/smartphones. It is configured to work in B/G mode (instead of default B/G/N) because it appeares to have a stronger signal that way.
Somewhere in settings (Wireless > Advanced Settings), there is a following screen:
Note the "Load Balancing" section above. Embedded help page says this:
Load Balancing
Load balancing enables the access point to reject any newer wireless client to associate when the utilization reaches the configured threshold. If you do not want it, select Disabled.
Administration manual makes it a little bit clearer what's the intended use for this feature:
First question: In which scenario would it make sense to load balance clients between SSID's emitted from same AP? From my understanding of wireless networks, a single AP would become saturated with max 25 clients, and in my mind, it is pointless to load balance on the same device, all while sharing same channel and BSSID. Please someone correct me if I'm wrong.
(I'll try to sneak in two more related question, if anyone is able to answer them, so I don't repeat similar questions.)
Second (sub)question: Manual says that "utilization" is actually current CPU utilization of the unit. Does it mean that if utilization is near 100% most of the time, unit is becoming saturated and is working sub-optimally? It's weird to me that a single AP unit (and a quite pricey one at that!) would get to 100% utilization with some 10-15 clients…?
Third (sub)question: Is capacity of AP to handle more clients going to improve when N-mode is disabled (the way I did), and AP is set to work in G (or mixed B/G) mode?
Best Answer
The purpose of load balancing is not for a scenario where there's just one AP. It's intended for a scenario with multiple APs. When you set up multiple APs, you always put them not-too-far from each other. You want the APs to overlap, a little, to be able to hop between APs. You don't want one APs signal to completely die out before getting into the next APs coverage, because then you'd have disconnections when the first APs signal has already died out, but the next APs signal is not there yet, or too weak.
So, you have overlaps. This is where the load balancing comes in. If you're standing in a place where you're picking up signals from 2 APs, the device will naturally prefer the one with a stronger signal. But if that AP is already at it threshold, it will push the device to the next AP.
The purpose is to balance the load between AP, as to not overload them as devices, and also to balance the network throughput between router ports, giving everyone about the same speed
You COULD also use this threshold with just one AP, if you really want. Then the AP will just deny devices over its threshold. Not a smart idea in any case I can think of, but just said this to further bring out the idea of load balancing.
Also, it's not "load balancing between SSIDs" on the same AP. The load balancing is per SSID, between APs.
Hope all is clear.
Sorry, me not sure about the other 2 questions. Leaving that for others :)