Cisco Access Points with Tri-Radio

Cisco access points with tri-radio

A Cisco access point with tri-radio is a wireless device that

  • operates three radios designed for high density environments

  • runs one dedicated 2.4-GHz 4x4 mode radio and one 5-GHz 8x8 mode radio by default, and

  • enables the 8x8 radio to split into two independent 5-GHz 4x4 radios when dual radio mode is enabled.

Tri-radio operational modes and configuration

Access Points with three radios are designed for high density environments. The APs by default run one dedicated 2.4-GHz 4x4 mode radio and one 5-GHz 8x8 mode radio. In the default mode, the radios are managed by the Flexible Radio Assignment (FRA), and the Dual Radio Mode is in the disabled state indicating that the radios have either been assigned as client serving 8x8 radio or have not yet been evaluated by FRA.

When you enable the dual radio mode setting, the 8x8 radio is split to two independent 5-GHz 4x4 radios. In this mode, slot 1 and slot 2 are active independent 4x4 radio interfaces. They can serve different user groups with different assigned channels.


Note

To disable the dual radio mode, you must first disable the admin status of the subordinate radio. Otherwise, a warning message is displayed.

A tri-radio AP has upto two configurable 5-GHz radios. The following table describes the radio role and its deployment benefits:

Table 1. 5-GHz radio operational modes and criteria

Radio Role

Driving Factors

Radio 1

Radio 2

8x8 Client-Serving

None

  • Preferred operation: 160 MHz or 80 + 80 MHz

  • Higher MU-MIMO stations

  • Required higher number of Spatial Streams (SS)

4x4 Client-Serving

4x4 Client-Serving

  • Preferred operation: 80 MHz or below

  • High Capacity in low or medium density

  • Directional antenna units (Coverage Slicing)

4x4 Client-Serving

4x4 Monitor

  • Preferred operation: 80 MHz or below

  • Lower MU-MIMO stations

  • Better channel reuse in high density

  • Monitoring application requires 4x4 Rx

The following table lists the different radio modes and roles supported by the AP:

Table 2. Tri-radio AP radio configuration

Setup

Radio Mode

Maximum Radio Capability

Dual Role Mode

1

 2.4-GHz + 5-GHz

2.4-GHz, 4 antennas, 4SS, and 20 MHz

5-GHz, 8 antennas, 4SS, and 160 MHz

Disabled

2

 5-GHz + 5-GHz

2.4-GHz, 4 antennas, 4SS, and 20 MHz

5-GHz, 4 antennas, 4SS, and 80 MHz

5-GHz, 4 antennas, 4SS, and 80 MHz

Enabled

In the Cisco IOS XE 17.2.1 Release, FRA manages the role assignment for each radio independently. You can set the radio mode as automatic or manual, and select either Client-Serving role or Monitor role as the radio role. Based on the dual radio mode configuration, the role selection is available for one or for both interfaces.

Guidelines and restrictions for tri-radio access points

  • Dual radio mode is disabled in the manual mode by default.

  • You must manually enable the slot 2 radio on the AP. By default it is disabled.

  • When you change the dual radio mode, the AP reboots without any notification.

  • The tri-radio support for AP with external antenna is as follows:

    • RP-TNC antenna is supported in Cisco Catalyst 9130AX Series APs.

    • The C-ANT9101, C-ANT9102, and C-ANT9103 antennas on Cisco Catalyst 9130AX Series APs support 2 radios (2.4-GHz (4x4) and 5-GHz (8x8)). This antennas does not support two 5-GHz (4x4) radios due to hardware limitation.

Enable or disable tri-radio on Cisco aps

Use this task to control tri-radio functionality on all supporting Cisco APs that join the controller.

Procedure

ap triradio { disable | enable}

Example:

Device# ap triradio enable

Enables or disables tri-radio on all the supporting Cisco APs that join this controller.

Tri-radio is now enabled or disabled on all supporting Cisco APs connected to this controller.

Configure 5-GHz dual radio mode for AP (GUI)

Before you begin

Follow these steps to configure 5-GHz dual radio mode for AP using GUI:

Procedure

Step 1

Choose Configuration > Wireless > Access Points.

Step 2

On the Access Points page, click the 5 GHz Radios section and select a Cisco 9130 Series AP from the list.

The Edit Radios 5 GHz Band window is displayed.

Step 3

In the General area of the edit window, click the Dual Radio Mode slider to Enable the mode.

A warning message is displayed informing that changing the Dual Radio Mode will reboot the AP.

Step 4

Click Update & Apply to Device.

Configure the dual radio mode and enable slots (CLI)

Configure dual radio mode on Cisco APs to enable flexible radio operation and optimize wireless coverage.
Dual radio mode allows Cisco APs to operate with enhanced radio flexibility, supporting both dual and tri-radio configurations. This is useful for environments requiring optimized wireless performance and coverage management.

Procedure

Step 1

(Optional) Disable the 802.11a radio on Cisco AP.

Example:

Device# ap name ap-name dot11 5ghz slot slot-number shutdown

Example:

Device# ap name ap-name dot11 5ghz slot 1 shutdown

Disables the 802.11a radio on Cisco AP.

Step 2

Configure the 802.11a dual radio on the AP.

Example:

Device# ap name ap-name dot11 5ghz slot 1 dual-radio mode mode-option

Example:

Device# ap name ap-name dot11 5ghz slot 1 dual-radio mode enable

Configures the 802.11a dual radio on the AP. Use the disable keyword to disable the dual-radio.

Step 3

Enable the 802.11a radio on Cisco AP.

Example:

Device# ap name ap-name no dot11 5ghz slot slot-number shutdown

Example:

Device# ap name ap-name no dot11 5ghz slot 1 shutdown

Enables the 802.11a radio on Cisco AP.
The dual radio mode is configured and the specified slots are enabled, allowing the AP to operate with the configured radio settings.

Set radio roles for slots (CLI)

Set specific radio roles (auto, manual monitor, or manual client-serving) for AP slots to optimize wireless coverage and monitoring capabilities.
This procedure applies only when Flexible Radio Assignment (FRA) is enabled. Radio role configuration allows you to control whether a slot operates in client-serving mode or monitor mode for network optimization.

Procedure

Step 1

Disable the radio on the AP.

Example:

Device# ap name ap-name dot11 5ghz shutdown

Disables the radio on the AP.

Step 2

Set the radio role for the specified slot.

Example:

Device# ap name ap-name dot11 frequency-band slot slot-id radio role role-type

Example:

Device# ap name ap-name dot11 5ghz slot 2 radio role manual monitor

Sets the radio role manual to either client serving or monitor.

Step 3

Enable the radio on the AP.

Example:

Device# ap name ap-name no dot11 frequency-band shutdown

Example:

Device# ap name ap-name no dot11 5ghz shutdown

Enables the radio on the AP.

Note

 

The RRM dynamic channel allocation (DCA) algorithm changes the radio role for slot2 and standby 5-GHz radio to monitor mode if:

  • The metric for the standby channel is not exhaustive (or)

  • The available channel is not suitable for standby 5-GHz radio

The standby 5-GHz radio and slot2 role changes to client-serving mode once the DCA is able to locate a suitable channel for slot2 or the metric for the channel is suitable.

The radio role is configured for the specified slot, and the radio is enabled with the new role assignment. The AP will operate according to the configured role settings.

Configure the tri-radio dual radio role (CLI)

Set up tri-radio dual radio role configuration to optimize wireless coverage and monitoring capabilities.
Tri-radio access points support independent radio role configuration for each radio, allowing you to designate radios for client-serving or monitoring functions to optimize network performance and security.

Procedure

Step 1

Configure the 802.11a radio role independently for each supporting AP's radio.

Example:

Device# ap name ap-name dot11 5ghz slot slot-number radio role role-mode function

Example:

Device# ap name 9130axtrial dot11 5ghz slot 1 radio role manual monitor

The channel and the Tx power values can be configured when the radio role is set to manual mode.

Step 2

Configure the 802.11b radio role independently for the supporting AP's radio.

Example:

Device# ap name ap-name dot11 24ghz slot 0 radio role role-mode function

Example:

Device# ap name 9130axtrial dot11 24ghz slot 0 radio role manual client-serving
The tri-radio dual radio roles are configured, with each radio optimized for its designated function of either client-serving or monitoring.

Tri-radio configuration verification on the controller

To verify that the dual radio mode is enabled, use the following show command: 

  • Device# show ap name APXXXX.4XXX.04XX config slot 1 | inc Dual
 Dual Radio Capable                            : True
 Dual Radio Mode                               : Enabled   
 Dual Radio Operation mode                     : Auto

To verify the tri-radio status, use the following show command: 

  • 
Device# show ap triradio status
Tri-Radio Status : Enabled

To verify that the slots are enabled and up, use the following show commands: 

  • Device# show ap triradio summary
AP Name                          Mac Address       Slot        Admin State     Oper State
-----------------------------------------------------------------------------------------
APXXXX.4XXX.04XX                 04eb.409e.89c0    2           Enabled         Up 
  • Device# show ap dot11 5ghz summary
AP Name                           Mac Address     Slot    Admin State    Oper State    Width    Txpwr           Channel                             Mode
---------------------------------------------------------------------------------------------------------------------------------------------------------
APXXXX.4XXX.04XX                  04XX.40XX.8XXX  1       Enabled        Up            20       *5/8 (14 dBm)   (36)*                               Local     
APXXXX.4XXX.04XX                  04XX.40XX.8XXX  2       Enabled        Up            20       *8/8 (1 dBm)    (36)*

To verify that the radio role is set, use the following show command: 

  • show ap name ap-name config slot <slot_number> | i Radio
Radio Type                                    : 802.11ax - 5 GHz
Radio Subband                                 : All
Radio Role                                    : Auto
Radio Mode                                    : Local
Radio SubType                                 : Main