AMX NXA-WAPZD1000, Operation/Reference Manual, Page: 77 / 154

Configure Tab
73 NXA-WAPZD1000 ZoneDirector Smart WLAN Controller
Load Balancing
Enabling load balancing can improve WLAN performance by helping to spread the client load between nearby
access points, so that one AP does not get overloaded while another sits idle. The load balancing feature can be
controlled from within the Browser-Based Configuration Pages to balance the number of clients per radio on
adjacent APs. “Adjacent APs” are determined by the NXA-WAPZD1000 at startup by measuring the RSSI
during channel scans. After startup, the NXA-WAPZD1000 uses subsequent scans to update the list of
adjacent radios periodically and when a new AP sends its first scan report. When an AP leaves, the NXA-
WAPZD1000 immediately updates the list of adjacent radios and refreshes the client limits at each affected
AP.
Once the NXA-WAPZD1000 is aware of which APs are adjacent to each other, it begins managing the client
load by sending desired client limits to the APs. These limits are “soft values” that can be exceeded in several
scenarios, including: (1) when a client’s signal is so weak that it may not be able to support a link with another
AP, and (2) when a client’s signal is so strong that it really belongs on this AP.
The APs maintain these desired client limits and enforce them once they reach the limits by withholding probe
responses and authentication responses on any radio that has reached its limit.
Key points on load balancing:

These rules apply only to client devices; the AP always responds to another AP that is attempting to
set up or maintain a mesh network.

Load balancing does not disassociate clients already connected.

Load balancing takes action before a client association request, reducing the chance of client
misbehavior.

The process does not require any time-critical interaction between APs and the NXA-WAPZD1000.

Provides control of adjacent AP distance with safeguards against abandoning clients.

Can be disabled on a per-WLAN basis; for instance, in a voice WLAN, load balancing may not be
desired due to voice roaming considerations.

Background scanning must be enabled on the WLAN for load balancing to work.
To enable Load Balancing globally:
1.
Go to Configure > Access Points.
2.
In Access Point Policies, click the Enable button next to Load Balancing.
To disable Load Balancing on a per-WLAN basis:
1.
Go to Configure > WLANs.
2.
Click the Edit link beside the WLAN for which you want to disable load balancing.
3.
Click the Advanced Options link to expand the options.
4.
Click the Disable button next to Load Balancing.