Cisco Access Points with Tri-Radio

Cisco Access Points with Tri-Radio

This topic describes the Tri-Radio feature for Cisco Access Points (APs).

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

2.4-GHz + 5-GHz

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

5-GHz, 8 antennas, 8SS, and 80 MHz

Disabled

3

2.4-GHz + 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 set to Auto by default. FRA manages the dual radio mode in Auto mode.

  • 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.

Configuring Tri-Radio

Configuring Tri-Radio for AP (GUI)

Procedure

Step 1

Choose Configuration > Radio Configurations > Network.

The Network > 5 GHz Radios page is displayed.

Step 2

In the General tab, select the Tri-Radio Mode check box to enable the Tri-Radio mode.

Step 3

Click Apply

Configuring the Tri-Radio (CLI)

In Cisco IOS XE Dublin 17.13.1, the ap tri-radio command cannot be configured, since the Tri-radio settings are enabled by default, and cannot be disabled.

Procedure

  Command or Action Purpose

Step 1

configure terminal

Example:

Device# configure terminal

Enters global configuration mode.

Step 2

[no] ap tri-radio

Example:

Device(config)# ap tri-radio

Configures all supporting tri-radio AP's dual radio role in auto mode. Use the [no] form of the command to disable the feature.

Configuring 5-GHz Dual Radio Mode for AP (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 Edit Radios 5-GHz Band > Configure > General tab, under Dual Radio Mode, select one from the following radio button options

  • Auto: Permits FRA to decide the mode for this AP.

  • Enabled: Enables Dual Radio mode for this AP.

  • Disabled: Disables Dual Radio mode for this AP.

Step 4

Click Update & Apply to Device.

Configuring the Dual Radio Mode and Enabling Slots (CLI)

Procedure

  Command or Action Purpose

Step 1

ap name ap-name dot11 5ghz slot { 1 | 2 } shutdown

Example:

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

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

Step 2

ap name ap-name dot11 5ghz slot 1 dual-radio mode { disable | enable| auto }

Example:

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

Configures the 802.11a dual and tri-radio on the AP. Enable auto to allow RRM to switch the AP between dual radio or tri radio mode based on the channel width configuration. In auto mode, the slot 2 state is managed by the RRM. Use the disable keyword to disable the dual-radio.

Note

 
When the AP is set to auto mode, the dual radio mode is disabled by default.

Step 3

ap name ap-name no dot11 5ghz slot { 1 | 2 } shutdown

Example:

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

Enables the 802.11a radio on Cisco AP.

Setting Radio Roles for Slots

The following section is applicable only if FRA is enabled.

Procedure

  Command or Action Purpose

Step 1

ap name ap-name dot11 { 24ghz | 5ghz } shutdown

Example:

Device# ap name ap-name dot11 5ghz shutdown

Disables the radio on the AP.

Step 2

ap name ap-name dot11 { 24ghz | 5ghz } slot <slot ID> radio role { auto | manual { monitor | client-serving} }

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

ap name ap-name no dot11 { 24ghz | 5ghz } 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.

Configuring the Tri-Radio Dual Radio Role (CLI)

Procedure

  Command or Action Purpose

Step 1

ap name ap-name dot11 5ghz slot { 1 | 2 } radio role { auto| manual { client-serving | monitor}

Example:

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

Configures the 802.11a radio role independently for each supporting AP's radio. The channel and the Tx power values can be configured when the radio role is set to manual mode.

Step 2

ap name ap-name dot11 24ghz slot 0 radio role { auto| manual { client-serving | monitor}

Example:

Device# ap name 9130axtrial dot11 24ghz slot 0 radio role manual client-serving

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

Verifying Tri-Radio Configuration 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