Configuring Co-Located APs in Load Balance Groups

You can configure APs that are co-located in an open area, such as a classroom, a conference hall, or an entrance lobby, to act as a load balance group. Load balancing distributes clients across the co-located APs that are members of the load balance group. The co-located APs should provide the same SSID, have Line-of-Sight (LoS) between each other, and be deployed on multiple channels with overlapping coverage.

Assign an AP's radio to the load balance group for the client distribution to occur. Load balancing occurs only among the assigned AP radios of the load balance group. Each radio can be assigned only to one load balance group. Multiple radios on the same AP do not have to be in the same load balance group. The radios that you assign to the load balance group must be on APs that are controlled by the same controller.

The load balance group uses one or more WLAN services for all APs assigned to the load balance group. You can configure two types of load balance groups:

• Client Balancing load group – performs load balancing based on the number of clients across all APs in the group and only for the WLANs assigned to the load group. This is different from load control in the Radio Preference group— load control APs make decisions in isolation from each other.
• Radio Preference load group – performs band preference steering and load control. Band preference steering is a mechanism to move 11a-capable clients to the 11a radio on the AP, relieving congestion on the 11g radio. No balancing is done between the 11a and 11g radios. Load control is disabled by default. A radio load group executes band preference steering and/or load control across the radios on each AP in the group. Each AP balances in isolation from the other APs, but all APs in the load group have the same configuration related to the band preference and load control.

Client balancing on the controller is AP-centric and requires no input from the client. The AP radios in the client balance group share information with secure (AES) messaging using multicast on the wired network. All APs in a client balance group must be in the same SIAPP cluster to ensure that each AP can reach all other APs in the client balance group over the wired subnet. If the APs in a client balance group are not in the same SIAPP cluster, client balancing happens independently within the subgroups defined by SIAPP clusters.

The benefits of configuring your co-located APs that are controlled by the same controller as a client balance group are the following:

• Resource sharing of the balanced AP
• Efficient use of the deployed 2.4 and 5 GHz channels
• Reduce client interference by distributing clients on different channels
• Scalable 802.11 deployment: if more clients need to be served in the area, additional APs can be deployed on a new channel

You can assign a maximum of 32 APs to a client balance group. The following table lists the maximum number of load balance groups for each controller.

Currently, the following wireless AP models support load balance groups:

• AP39xx
• AP3801i
• AP3805 (i & e)
• AP3825 (i & e)
• AP3865e
• AP3765/67
• AP3705i
• AP3710 (i & e)
• AP3715 (i & e)

To create a load balance group, see Creating a Load Balance Group.