Disconnections issue - coverage for clients is normally close to -67

[Sam Caprio]

Hello everyone,
Need your assistance on below case.

We are experiencing intermittent Wi-Fi disconnections affecting iPhone users. Upon analyzing the signal strength, we found that their RSSI is typically around -67 dBm. Below are the RF profile data rate configurations for our access points:

• 5 GHz Band:
• Mandatory: 24 Mbps
• Supported: 36, 48, 54 Mbps
• 2.4 GHz Band:
• Mandatory: 24 Mbps
• Supported: 12, 18, 36, 48, 54 Mbps

Based on our observations, it appears that iPhone users may be facing coverage-related issues. To mitigate this, we are considering modifying the data rate settings for the 5 GHz band by adding 18 Mbps and 12 Mbps as supported rates. Additionally, we are thinking of changing the Client Network Preference setting in the DCA (Dynamic Channel Assignment) from its default value to "Connectivity" for both the 2.4 GHz and 5 GHz bands.

Furthermore, we have all MCS index values (ranging from 0 to 31) enabled in the RF profile. Could you confirm if this configuration is optimal, or would it be advisable to adjust these settings?

Additionally, could someone please explain the purpose of the Client Network Preference setting and under what circumstances it should be modified.

Our current deployment for the site does not appear to be a high-density environment, as many areas maintain signal levels close to -67 dBm.

Could you please advise on the best practices or recommended adjustments to effectively resolve these disconnection issues?

[JPavonM]

Yes, consider enabling basic rates 6Mbps and 12Mbps.

[Scott Fella]

I think it's a good start, but also make sure the issues isn't when the iPhone screen is off.  That might be a reason you see disconnections, but like you said, it can also be due to your data rates and or TX power levels.

[RxTx]

I don't like client RSSI -67 dBm, can be to low for your 5GHz band data rates. Check also Signal Quality SNR.

I will go with this settings for both bands:

12 Mbps Supported
18 Mbps Supported
24 Mbps Mandatory
36 Mbps Supported
48 Mbps Supported
54 Mbps Supported

I don't think Client Network Preference on Automatic has anything to do with your problem.

What are the Power Level AP's transmit on both bands ?

[Leo Laohoo]

What firmware is the controller on?

What AP models are currently being used?

[Haydn Andrews]

Few things

unless this is a highly dense AP deployment that was designed for those data rates I would do following

5 GHz enable all rates 12 and above

make 12Mbps the mandatory and remove the 24

TX SOP would make sure is automatic

Would also recommend a site survey to ensure there is adequate coverage and cell overlaps

For the SSID

Do you have the following enabled:

802.11k

802.11v

802.11r (if all clients support it on the SSID otherwise go adaptive) - you will find if this office style SSID you will be fine

Would also consider making it 5GHz only, Apple roaming metrics will stick to the 2.4 GHz band if they roam there unless it sees a 8dB stronger AP (when transmitting and 12dB when idle) and its roaming trigger is -70dB

Apple actually has a good paper on this here: https://support.apple.com/en-au/guide/deployment/dep98f116c0f/web