Environment : This article applies to all Aruba Instant Access Points running Aruba InstantOS 6.2.1.0-3.3.0.0 or higher.
In indoor environments, client devices often have a choice of multiple access points operating on different channels. As the client count increases on a particular channel of an access point, performance and speed of the clients on that channel gradually goes down.
Empirical testing at Aruba has shown that the number of clients on a given channel, not clients per access point, is the dominant predictor of data capacity. This is because closely spaced access points create an interference zone where Wi-Fi transmissions are detected by most access points and clients on the channel, so adding access points merely increases co-channel interference.
While the decision about which access point to choose is normally left to the client, ARM’s infrastructure-controlled load balancing forces the client to a ‘better’ channel using standard association response frames.
The command below helps us to understand the RF neighborhood with neighbor access points, their active channel and associated client count per channel. It also gives an idea if load enforcement is activated on AP which generally depends on below rule:
Current_associated >= Client_Threshold
IAP's send updates (such as client propagation information) in the form of Information Element (IE) within the probe request packets. Once the AP receives the update, it is checked across its own density map to decide if the AP falls with same RF neighborhood or not.
show ap debug spectrum-load-balancing x
(Where, x stands for radio: 0 or 1. 0 is for 5.GHz and 1 is for 2.4GHz)
IAP# show ap debug spectrum-load-balancing 0
Spectrum Load Balancing Status: RUNNING, Associated:1, Threshold:5 ===> Client Count Threshold
Spectrum Load Balancing Neighbor Table
--------------------------------------------
MAC Channel Client_Count Flags Recved_Seconds
--- ------- ------------ ----- --------------
00:24:6c:07:b2:60 48 0 VR 85
00:24:6c:24:24:50 165 3 VR 136
00:24:6c:33:06:00 165 9 V 281
00:24:6c:24:17:60 161 0 2180
00:24:6c:07:7e:80 36 0 S 296
Neighbor Flags: V - Valid; R - Is in Virtual RF Neighborhood; S - Same Channel
Note: The entry in the SLB neighbor table is aged out, if no entry from the neighbor AP is received in 5 mins (or) 300 seconds.
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