Cisco 8821 Manual page 79

Once Bridge mode is enabled, the VLAN tagging option will be available.
It is recommended to enable VLAN tagging for the SSID.
If VLAN tagging is utilized, ensure that the Cisco Meraki access point is connected to a switch port configured for trunk mode
allowing that VLAN.
If utilizing Cisco Meraki MS Switches, reference the Cisco Meraki MS Switch VoIP Deployment Guide.
https://meraki.cisco.com/lib/pdf/meraki_whitepaper_msvoip.pdf
If utilizing Cisco IOS Switches, use the following switch port configuration for ports that have Cisco Meraki access points
connected to enable 802.1q trunking.
Interface GigabitEthernet X
switchport trunk encapsulation dot1q
switchport mode trunk
mls qos trust dscp
On the Wireless > Configure > Access control page, the frequency band for the SSID to be used by the Cisco Wireless IP
Phone 8821 and 8821-EX can be configured as necessary.
It is recommended to select 5 GHz band only to have the Cisco Wireless IP Phone 8821 and 8821-EX operate on the 5 GHz
band due to have many channels available and not as many interferers as the 2.4 GHz band has.
If the 2.4 GHz band needs to be used due to increased distance, then Dual band operation (2.4 GHz and 5 GHz) should be
selected. Do not utilize the Dual band operation with Band Steering option.
Is recommended to disable data rates below 12 Mbps unless a legacy 2.4 GHz client needs to be able to connect to the Wireless
LAN.
Cisco Wireless IP Phone 8821 and 8821-EX Wireless LAN Deployment Guide
79