In a typical WLAN, getting the right balance between the number of APs functioning as sensors and APs providing WLAN service is a serious challenge. The challenge increases exponentially with increase in the size of the deployment. As a rule, approximately 1/3 of the APs within a site should be configured as sensors to provide adequate coverage and monitor WLAN activity. Determining the minimum number of sensor APs required, selecting the APs ideally located to work as sensors and provisioning them as sensors is a cumbersome process. The Smart-sensor feature automates this process using an algorithm.
In a Smart-RF monitored deployment, neighbor details and configuration updates are collected in the Smart-RF neighbor table. This information is used by the algorithm to create a cluster of cells, with each cell representing an AP. The algorithm then identifies APs with best coverage area and provisions them as sensors—this process is referred to as smart-sensor calibration. The algorithmic calculations vary depending on the cell size. The current implementation provides two algorithms based on whether the AP deployment is dense (small cell size) or sparse (big cell size).
You can use the smart-sensor-status-timer command to set a timer to initiate a check of radio sensor status. If all sensors are "Off", recalibration for the smart-sensor feature is automatically triggered.
Smart-sensor is supported on both tri-radio and dual-radio APs. The Smart-sensor feature can be configured to select either both tri-radio and dual-radio APs or only tri-radio APs from the Smart-RF neighbor table and auto-provision them as sensors. By default, Smart-sensor selects only tri-radio APs in mixed dual-radio and tri-radio deployments. You must disable the parameter tri-radio-only to enforce selection and provisioning of both tri-radio and dual-radio APs as sensors.
smart-sensor {algorithm|auto-trigger|band|tri-radio-only}
smart-sensor algorithm cell-size [dense|sparse]
smart-sensor {auto-trigger}
smart-sensor {band [smart-band-24GHz|smart-band-5GHz|smart-band-6GHz]}
smart-sensor tri-radio-only
smart-sensor algorithm cell-size [dense|sparse]
smart-sensor | Enables the Smart-sensor feature and configures the required parameters |
algorithm | Uses an algorithm to calibrate a cluster of cells and identify APs best suited to be provisioned as sensors. |
cell-size [dense|sparse] | Selects the algorithm to use based on the cell size. The options
are:
Note: By default
none of the algorithmic options is selected.
|
smart-sensor {auto-trigger|band [smart-band-24GHz|smart-band-5GHz|smart-band-6GHz]}
smart-sensor | Enables the Smart-sensor feature and configures the required parameters. |
smart-sensor auto-trigger | Optional. Enables/disables auto-triggering of
smart-sensor calibration. Note: The auto-trigger option is enabled by default. To disable
auto-trigger, issue the
no
smart-sensor auto-trigger command.The Smart-sensor feature uses an algorithmic function to identify the APs that are best suited to be provisioned as sensors. This algorithmic function is auto-triggered when the Smart-sensor feature is enabled for the first time. Auto-triggering of calibration is a one-time process, unless the smart-sensor-status-timer is enabled, in which case, re-calibration may occur automatically. In the event
that—post auto-provisioning of the APs as sensor—the number of
APs deployed changes or if the AP deployment pattern changes, a
re-calibration may be needed. Under certain conditions, if the
smart-sensor-status-timer is enabled, re-calibration will occur
automatically. Otherwise, to initiate re-calibration you must
manually issue the |
band [smart-band-24GHz|smart-band-5GHz|smart-band-6GHz] | Optional. Sets the band (2.4GHz/ 5GHz/ 6GHz) used in the neighbor
list collection process for the Smart-sensor feature. Options
are:
|
smart-sensor tri-radio-only
smart-sensor | Enables the Smart-sensor feature and configures the required parameters |
tri-radio-only | This option restricts the Smart-sensor algorithm to
only
select and provision tri-radio
APs as sensors. Note: It is enabled by
default.
If your deployment consists of a mix of
tri-radio and dual-radio APs, execute the |
nx9500-6C8809(config)#smart-rf-policy smt-sensor
nx9500-6C8809(config-smart-rf-policy-smt-sensor)#smart-sensor
nx9500-6C8809(config-smart-rf-policy-test)#smart-sensor band smart-band-24GHz
nx9500-6C8809(config-smart-rf-policy-smt-sensor)#smart-sensor algorithm cell-size [dense|sparse]
Note
Select 'dense' if the cell size is small (distance between neighboring APs is small). Select 'sparse' if the cell size if large (distance between neighboring APs is large).nx9500-6C8809(config-smart-rf-policy-smt-sensor)#show context smart-rf-policy smt-sensor no select-shutdown smart-sensor smart-sensor algorithm cell-size sparse smart-sensor auto-trigger smart-sensor band smart-band-24GHz smart-sensor tri-radio-only nx9500-6C8809(config-smart-rf-policy-smt-sensor)#
Note
The auto-trigger and tri-radio-only options are enabled by default.nx9500-6C8809(config-smart-rf-policy-smt-sensor)#no smart-sensor tri-radio-only
nx9500-6C8809(config-rf-domain-smt-sensor)#use smart-rf-policy smt-sensor
no (smart-rf-policy-config-mode-command) | Disables the smart-sensor feature |