Wireless Access

Hi community,

I have a doubt about client aware mode within ARM feature. From the user guide:

When Enabled, ARM does not change channels for the Instant APs with active clients, except for high-priority events such as RADAR or excessive noise. This feature must be enabled in most deployments for a stable WLAN. If the Client Aware mode is Disabled, the Instant AP may change to a more optimal channel, that may disrupt the current client traffic for a while. The Client aware option is Enabled by default.
NOTE: When Client aware is disabled, channels can be changed even when the clients are active on a BSSID.

My question is, if I disable client aware and the AP wants to change the channel, will the client traffic be disrupted? Does it depends on the client type? I have read that Aruba and other vendors can change the channel while the clients are connected and they are not affected because they use CSA.

https://community.arubanetworks.com/t5/Wired-Intelligent-Edge-Campus/How-CSA-works/ta-p/233787

Do most of the today clients support CSA? Is CSA enabled/disabled by default on Instant APs?

Regards,

Julián

Hi,

Any suggestion? Only that yesterday I saw two contiguous APs in the same 5 GHz channel, and because they have many clients, the channel was at more than 50% utilization, which I've never seen in the 5-GHz band. The rest of my APs were at different channels and with less than 5% of utilization, which was fine. I expect today these two APs have changed channel.

Regards,

Julián

Hi guys,

Any idea?

Regards,

Julián

If you want a single sentence, I would say "don't worry about it".

You would have to enable CSA in the SSID profile for the AP to send the destination channel to clients.  Some clients do not like CSA, so I never enable CSA, really.

Whether there is disruption or not depends on the client and the application currently in use.  If the application is delay sensitive, it might be noticeable, but it depends on the client.  On the other hand, there are voice clients that roam during a call and there is no discernable disruption.  Access points are constantly changing channels to scan other channels, and there is no disruption.

In practice, I don't give a second thought to Client Aware, unless I feel like the access points do not change channel enough.  In ArubaOS 8.x and above with an MM, ARM is not in the picture and Client Aware is not available.

Hi Colin,

Very good explanation. When you say "In practice, I don't give a second thought to Client Aware, unless I feel like the access points do not change channel enough.", do you mean you only disable Client Aware when the access points don't change channel enough and you feel the current channel plan is not good enough?

In my case, the day after the two contiguous APs kept on the same 5-GHz channel, and in that case it would be a good idea to disable Client Aware for a while to give a chance to the APs to change the channel, right?

Regards,

Julián

I would disable it on initial deployment if I was impatient.  I would not touch it after that.  That is my personal experience.

If two contiguous APs are on the same channel, sometimes you are so dense that many APs are next to contiguous APs.   And it is possible the channel experience is not worse than other channels.  Or, you are using 80 or 40mhz channels and you have limited options.

Please read the ARM supplement here:  https://community.arubanetworks.com/aruba/attachments/aruba/unified-wired-wireless-access/7592/1/ARM%20Doc%20Supplement.pdf to determine why your access points are on the channels that they are.

Hi Colin,

Many thanks, valuable information.

Regards,

Julián