Cisco Wireless LAN Controller Configuration Guide, Release 7.0
Chapter 13 - Configuring Cisco CleanAir
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Configuring Cisco CleanAir

Table Of Contents

Configuring Cisco CleanAir

Overview of Cisco CleanAir

Role of the Controller

Benefits

Types of Interferences

Supported Access Point Modes

Guidelines

Configuring Cisco CleanAir on the Controller

Using the GUI to Configure Cisco CleanAir on the Controller

Using the CLI to Configure Cisco CleanAir on the Controller

Configuring Cisco CleanAir on an Access Point

Using the GUI to Configure Cisco CleanAir on an Access Point

Using the CLI to Configure Cisco CleanAir on an Access Point

Monitoring the Interference Devices

Using GUI to monitor the Interference Device

Using GUI to monitor the Interference Device

Monitoring the Air Quality of Radio Bands

Using the GUI to Monitor the Air Quality of Radio Bands

Using the CLI to Monitor the Air Quality of Radio Bands

Using the GUI to Monitor the Worst Air Quality of Radio Bands

Using the CLI to Monitor the Air Quality of Radio Bands

Configuring a Spectrum Expert Connection


Configuring Cisco CleanAir


This chapter describes how to configure Cisco CleanAir functionality on the controller and lightweight access points. It contains these sections:

Overview of Cisco CleanAir

Configuring Cisco CleanAir on the Controller

Configuring Cisco CleanAir on an Access Point

Monitoring the Air Quality of Radio Bands

Configuring a Spectrum Expert Connection

Overview of Cisco CleanAir

Wireless LAN systems operate in unlicensed 2.4- and 5-GHz industrial, scientific, and medical (ISM) bands. Many devices, such as microwave ovens, cordless phones, and Bluetooth devices also operate in these bands and can negatively affect Wi-Fi operations. Some of the most advanced WLAN services, such as voice over wireless and IEEE 802.11n radio communications, could be significantly impaired by the interference caused by other legal users of the ISM bands. The integration of Cisco CleanAir functionality into the Cisco Unified Wireless Network addresses this problem of radio frequency (RF) interference. The Cisco CleanAir feature, available in controller software release 7.0, enables you to identify and track non-Wi-Fi sources of interference, adjust your network configuration for optimal performance, identify threats from malicious devices, and allow your WLAN to coexist with other wireless devices.

A Cisco CleanAir system consists of CleanAir-enabled access points, controllers, and WCS. Currently, only Cisco Aironet 3500 series access points can be configured for Cisco CleanAir. These access points collect information about all devices that operate in the ISM bands, identify and evaluate the information as a potential interference source, and forward it to the controller. The controller controls the access points, collects spectrum data, and forwards information to WCS or a Cisco mobility services engine (MSE) upon request. The controller provides a local user interface to configure basic CleanAir features and display basic spectrum information. WCS provides an advanced user interface for configuring Cisco CleanAir features, displaying information, and keeping records. The MSE is optional for the basic feature set but required for advanced features such as tracking the location of non-Wi-Fi interference devices.

Role of the Controller

The controller performs these tasks in a Cisco CleanAir system:

Configures Cisco CleanAir capabilities on the access point

Provides interfaces (GUI, CLI, and SNMP) for configuring Cisco CleanAir features and retrieving data

Displays spectrum data

Collects and processes air quality reports from the access point and stores them in the air quality database

Collects and processes interference device reports (IDRs) from the access point and stores them in the interference device database

Forwards spectrum data to WCS and the MSE

Benefits

Cisco CleanAir is a spectrum intelligence solution designed to proactively manage the challenges of a shared wireless spectrum. It allows you to see all of the users of the shared spectrum (both native devices and foreign interferers). It also enables you or your network to act upon this information. For example, you could manually remove the interfering device, or the system could automatically change the channel away from the interference.

For every device operating in the unlicensed band, Cisco CleanAir tells you what it is, where it is, how it is impacting your wireless network, and what actions you or your network should take. It simplifies RF so that you do not have to be an RF expert.

Types of Interferences

Cisco CleanAir can detect interference, report on the location and severity of the interference, and recommend different mitigation strategies. Two such mitigation strategies are persistent device avoidance and spectrum event-driven RRM.

Wi-Fi chip-based RF management systems share these characteristics:

Any RF energy that cannot be identified as a Wi-Fi signal is reported as noise.

Noise measurements that are used to assign a channel plan tend to be averaged over a period of time to avoid instability or rapid changes that can be disruptive to certain client devices.

Averaging measurements reduces the resolution of the measurement. As such, a signal that disrupts clients might not look like it needs to be mitigated after averaging.

All RF management systems available today are reactive in nature.

Cisco CleanAir is different and can positively identify not only the source of the noise but also its location and potential impact to a WLAN. Having this information allows you to consider the noise within the context of the network and make intelligent and, where possible, proactive decisions. For CleanAir, two types of interference events are common:

Persistent interference

Spontaneous interference

Persistent interference events are created by devices that are stationary in nature and have intermittent but largely repeatable patterns of interference. For example, consider the case of a microwave oven located in a break room. Such a device might be active for only 1 or 2 minutes at a time. When operating, however, it can be disruptive to the performance of the wireless network and associated clients. Using Cisco CleanAir, you can positively identify the device as a microwave oven rather than indiscriminate noise. You can also determine exactly which part of the band is affected by the device, and because you can locate it, you can understand which access points are most severely affected. You can then use this information to direct RRM in selecting a channel plan that avoids this source of interference for the access points within its range. Because this interference is not active for a large portion of the day, existing RF management applications might attempt to again change the channels of the affected access points. Persistent device avoidance is unique, however, in that it remains in effect as long as the source of interference is periodically detected to refresh the persistent status. The Cisco CleanAir system knows that the microwave oven exists and includes it in all future planning. If you move either the microwave oven or the surrounding access points, the algorithm updates RRM automatically.

Spontaneous interference is interference that appears suddenly on a network, perhaps jamming a channel or a range of channels completely. The Cisco CleanAir spectrum event-driven RRM feature allows you to set a threshold for air quality (AQ) that, if exceeded, triggers an immediate channel change for the affected access point. Most RF management systems can avoid interference, but this information takes time to propagate through the system. Cisco CleanAir relies on AQ measurements to continuously evaluate the spectrum and can trigger a move within 30 seconds. For example, if an access point detects interference from a video camera, it can recover by changing channels within 30 seconds of the camera becoming active. Cisco CleanAir also identifies and locates the source of interference so that more permanent mitigation of the device can be performed at a later time.


Note Spectrum event-driven RRM can be triggered only by Cisco CleanAir-enabled access points in local mode.


Supported Access Point Modes

Only Cisco CleanAir-enabled access points using the following access point modes can perform Cisco CleanAir spectrum monitoring:

Local—In this mode, each Cisco CleanAir-enabled access point radio provides air quality and interference detection reports for the current operating channel only.

Hybrid-REAP—When a hybrid-REAP access point is connected to the controller, its Cisco CleanAir functionality is identical to local mode.

Monitor—When Cisco CleanAir is enabled in monitor mode, the access point provides air quality and interference detection reports for all monitored channels; does not participate in AQ HeatMap in WCS.

The following options are available:

All— All channels

DCA—Channel selection governed by the DCA list

Country—All channel legal within a regulatory domain

SE-Connect—This mode enables a user to connect a Spectrum Expert application running on an external Microsoft Windows XP or Vista PC to a Cisco CleanAir-enabled access point in order to display and analyze detailed spectrum data. The Spectrum Expert application connects directly to the access point, bypassing the controller. An access point in SE-Connect mode does not provide any Wi-Fi, RF, or spectrum data to the controller. See the "Configuring a Spectrum Expert Connection" section for instructions on establishing a Spectrum Expert console connection.

Guidelines

Follow these guidelines when using Cisco CleanAir functionality:

The Cisco 2100 Series Controller and Controller Network Modules support up to 75 device clusters (unique interference devices detected by a single or multiple radios) and up to 300 device records (information about an interference device detected by a single radio). The Cisco 4400 Series Controllers, Cisco WiSM, and Catalyst 3750G Wireless LAN Controller Switch support up to 750 device clusters and up to 3,000 device records. The Cisco 5500 Series Controllers support up to 2,500 device clusters and up to 10,000 device records.

The amount of power required for processing spectrum data limits the number of monitor-mode access points that can be used for Cisco CleanAir monitoring. The Cisco CleanAir system supports up to 6 monitor-mode access points on the Cisco 2100 Series Controller and Controller Network Modules; up to 25 monitor-mode access points on the Cisco 4400 Series Controllers, the Catalyst 3750G Wireless LAN Controller Switch, and each Cisco WiSM controller; and up to 75 monitor-mode access points on the Cisco 5500 Series Controllers. This limitation affects only Cisco CleanAir functionality.

Access points in monitor mode do not transmit Wi-Fi traffic or 802.11 packets. They are excluded from radio resource management (RRM) planning and are not included in the neighbor access point list. IDR clustering depends on the controller's ability to detect neighboring in-network access points. Correlating interference device detections from multiple access points is limited between monitor-mode access points.

Controllers have limitations on the number of monitor mode AP's that they can support. This is because, a monitor mode AP saves data for all the channels.

Configuring Cisco CleanAir on the Controller

This section describes how to configure Cisco CleanAir functionality on the 802.11a/n or 802.11b/g/n network using either the controller GUI or CLI.


Note See the "Configuring Cisco CleanAir on an Access Point" section to enable or disable Cisco CleanAir functionality for a specific access point, rather than globally across the network. For example, you may want to enable Cisco CleanAir globally on the 802.11a/n network but then disable it for a particular access point on that network.


Using the GUI to Configure Cisco CleanAir on the Controller

To configure Cisco CleanAir functionality on the controller using the controller GUI, follow these steps:


Step 1 Choose Wireless > 802.11a/n or 802.11b/g/n > CleanAir to open the 802.11a (or 802.11b) > CleanAir page (see Figure 13-1).

Figure 13-1 802.11a > CleanAir Page

Step 2 Select the CleanAir check box to enable Cisco CleanAir functionality on the 802.11a/n or 802.11b/g/n network, or unselect it to prevent the controller from detecting spectrum interference. The default value is selected.

Step 3 Select the Report Interferers check box to enable the Cisco CleanAir system to report any detected sources of interference, or unselect it to prevent the controller from reporting interferers. The default value is selected.

Step 4 Make sure that any sources of interference that need to be detected and reported by the Cisco CleanAir system appear in the Interferences to Detect box and any that do not need to be detected appear in the Interferences to Ignore box. Use the > and < buttons to move interference sources between these two boxes. By default, all interference sources are detected. The possible sources of interference are as follows:

Bluetooth Paging Inquiry—A Bluetooth discovery (802.11b/g/n only)

Bluetooth Sco Acl—A Bluetooth link (802.11b/g/n only)

Generic DECT—A digital enhanced cordless communication (DECT)-compatible phone

Generic TDD—A time division duplex (TDD) transmitter

Generic WaveformA continuous transmitter

Jammer—A jamming device

Microwave—A microwave oven (802.11b/g/n only)

Canopy—A canopy device

Radar—A radar device (802.11a/n only)

Spectrum 802.11 FH—An 802.11 frequency-hopping device (802.11b/g/n only)

Spectrum 802.11 inverted—A device using spectrally inverted Wi-Fi signals

Spectrum 802.11 non std channel—A device using nonstandard Wi-Fi channels

Spectrum 802.11 SuperG—An 802.11 SuperAG device

Spectrum 802.15.4—An 802.15.4 device (802.11b/g/n only)

Video Camera—An analog video camera

WiMAX Fixed—A WiMAX fixed device (802.11a/n only)

WiMAX Mobile—A WiMAX mobile device (802.11a/n only)

XBox—A Microsoft Xbox (802.11b/g/n only)


Note Access points that are associated to the controller send interference reports only for the interferers that appear in the Interferences to Detect box. This functionality allows you to filter out interferers that you do not want as well as any that may be flooding the network and causing performance problems for the controller or WCS. Filtering allows the system to resume normal performance levels.


Step 5 Configure Cisco CleanAir alarms as follows:

a. Select the Enable AQI (Air Quality Index) Trap check box to enable the triggering of air quality alarms, or unselect the box to disable this feature. The default value is selected.

b. If you selected the Enable AQI Trap check box in a., enter a value between 1 and 100 (inclusive) in the AQI Alarm Threshold text box to specify the threshold at which you want the air quality alarm to be triggered. When the air quality falls below the threshold level, the alarm is triggered. A value of 1 represents the worst air quality, and 100 represents the best. The default value is 35.

c. Select the Enable Interference Type Trap check box to trigger interferer alarms when the controller detects specified device types, or unselect it to disable this feature. The default value is selected.

d. Make sure that any sources of interference that need to trigger interferer alarms appear in the Trap on These Types box and any that do not need to trigger interferer alarms appear in the Do Not Trap on These Types box. Use the > and < buttons to move interference sources between these two boxes. By default, all interference sources trigger interferer alarms.

For example, if you want the controller to send an alarm when it detects a jamming device, select the Enable Interference Type Trap check box and move the jamming device to the Trap on These Types box.

Step 6 Click Apply to commit your changes.

Step 7 Trigger spectrum event-driven radio resource management (RRM) to run when a Cisco CleanAir-enabled access point detects a significant level of interference as follows:

a. Look at the EDRRM field to see the current status of spectrum event-driven RRM and, if enabled, the Sensitivity Threshold field to see the threshold level at which event-driven RRM is invoked.

b. If you want to change the current status of event-driven RRM or the sensitivity level, click Change Settings. The 802.11a (or 802.11b) > RRM > Dynamic Channel Assignment (DCA) page appears (see Figure 13-2).

Figure 13-2 802.11a > RRM > Dynamic Channel Assignment (DCA) Page

c. Select the EDRRM check box to trigger RRM to run when an access point detects a certain level of interference, or unselect it to disable this feature. The default value is selected.

d. If you selected the EDRRM check box in c., choose Low, Medium, or High from the Sensitivity Threshold drop-down list to specify the threshold at which you want RRM to be triggered. When the interference for the access point rises above the threshold level, RRM initiates a local dynamic channel assignment (DCA) run and changes the channel of the affected access point radio if possible to improve network performance. Low represents a decreased sensitivity to changes in the environment while High represents an increased sensitivity.

The EDRRM AQ threshold value for low sensitivity is 35, medium sensitivity is 50, and high sensitivity is 60.

The default value is Medium.

e. Click Apply to commit your changes.

Step 8 Click Save Configuration to save your changes.


Using the CLI to Configure Cisco CleanAir on the Controller

To configure Cisco CleanAir functionality on the controller using the controller CLI, follow these steps:


Step 1 Configure Cisco CleanAir functionality on the 802.11a/n or 802.11b/g/n network by entering this command:

config {802.11a | 802.11b} CleanAir {enable | disable} all

If you disable this feature, the controller does not receive any spectrum data. The default value is enable.

Step 2 Configure interference detection and specify sources of interference that need to be detected by the Cisco CleanAir system by entering this command:

config {802.11a | 802.11b} CleanAir device {enable | disable} type

where type is one of the following:

802.11-fh—An 802.11 frequency-hopping device (802.11b/g/n only)

802.11-inv—A device using spectrally inverted Wi-Fi signals

802.11-nonstd—A device using nonstandard Wi-Fi channels

802.15.4—An 802.15.4 device (802.11b/g/n only)

all—All interference device types (this is the default value)

bt-discovery—A bluetooth discovery (802.11b/g/n only)

bt-link—A bluetooth link (802.11b/g/n only)

canopy—A canopy device

cont-txA continuous transmitter

dect-like—A digital enhanced cordless communication (DECT)-compatible phone

jammer—A jamming device

mw-oven—A microwave oven (802.11b/g/n only)

radar—A radar device (802.11a/n only)

superag—An 802.11 SuperAG device

tdd-tx—A time division duplex (TDD) transmitter

video camera—An analog video camera

wimax-fixed—A WiMAX fixed device

wimax-mobile—A WiMAX mobile device

xbox—A Microsoft Xbox (802.11b/g/n only)


Note Access points that are associated to the controller send interference reports only for the interference types specified in this command. This functionality allows you to filter out interferers that may be flooding the network and causing performance problems for the controller or WCS. Filtering allows the system to resume normal performance levels.


Step 3 Configure the triggering of air quality alarms by entering this command:

config {802.11a | 802.11b} CleanAir alarm air-quality {enable | disable}

The default value is enable.

Step 4 Specify the threshold at which you want the air quality alarm to be triggered by entering this command:

config {802.11a | 802.11b} CleanAir alarm air-quality threshold threshold

where threshold is a value between 1 and 100 (inclusive). When the air quality falls below the threshold level, the alarm is triggered. A value of 1 represents the worst air quality, and 100 represents the best. The default value is 35.

Step 5 Enable the triggering of interferer alarms by entering this command:

config {802.11a | 802.11b} CleanAir alarm device {enable | disable}

The default value is enable.

Step 6 Specify sources of interference that trigger alarms by entering this command:

config {802.11a | 802.11b} CleanAir alarm device type {enable | disable}

where type is one of the following:

802.11-fh—An 802.11 frequency-hopping device (802.11b/g/n only)

802.11-inv—A device using spectrally inverted Wi-Fi signals

802.11-nonstd—A device using nonstandard Wi-Fi channels

802.15.4—An 802.15.4 device (802.11b/g/n only)

all—All interference device types (this is the default value)

bt-discovery—A Bluetooth discovery (802.11b/g/n only)

bt-link—A Bluetooth link (802.11b/g/n only)

canopy—A canopy device

cont-txA continuous transmitter

dect-like—A digital enhanced cordless communication (DECT)-compatible phone

jammer—A jamming device

mw-oven—A microwave oven (802.11b/g/n only)

radar—A radar device (802.11a/n only)

superag—An 802.11 SuperAG device

tdd-tx—A time division duplex (TDD) transmitter

video camera—An analog video camera

wimax-fixed—A WiMAX fixed device

wimax-mobile—A WiMAX mobile device

xbox—A Microsoft Xbox (802.11b/g/n only)

Step 7 Trigger spectrum event-driven radio resource management (RRM) to run when a Cisco CleanAir-enabled access point detects a significant level of interference by entering these commands:

config advanced {802.11a | 802.11b} channel cleanair-event {enable | disable}—Enables or disables spectrum event-driven RRM. The default value is disabled.

config advanced {802.11a | 802.11b} channel cleanair-event sensitivity {low | medium | high}—Specifies the threshold at which you want RRM to be triggered. When the interference level for the access point rises above the threshold level, RRM initiates a local dynamic channel assignment (DCA) run and changes the channel of the affected access point radio if possible to improve network performance. Low represents a decreased sensitivity to changes in the environment while high represents an increased sensitivity. The default value is medium.

Step 8 Save your changes by entering this command:

save config

Step 9 View the Cisco CleanAir configuration for the 802.11a/n or 802.11b/g/n network by entering this command:

show {802.11a | 802.11b} cleanair config

Information similar to the following appears:

Clean Air Solution............................... Enabled
Air Quality Settings:
    Air Quality Reporting........................ Enabled
    Air Quality Reporting Period (min)........... 15
    Air Quality Alarms........................... Enabled
    Air Quality Alarm Threshold.................. 35
Interference Device Settings:
    Interference Device Reporting................ Enabled
    Interference Device Types:
        TDD Transmitter.......................... Disabled
        Jammer................................... Disabled
        Continuous Transmitter................... Disabled
        DECT-like Phone.......................... Disabled
        Video Camera............................. Disabled
        WiFi Inverted............................ Disabled
        WiFi Invalid Channel..................... Disabled
        SuperAG.................................. Disabled
        Radar.................................... Disabled
        Canopy................................... Disabled
        WiMax Mobile............................. Disabled
        WiMax Fixed.............................. Disabled
Interference Device Alarms....................... Enabled
    Interference Device Types Triggering Alarms:
        TDD Transmitter.......................... Disabled
        Jammer................................... Enabled
        Continuous Transmitter................... Disabled
        DECT-like Phone.......................... Disabled
        Video Camera............................. Disabled
        WiFi Inverted............................ Enabled
        WiFi Invalid Channel..................... Enabled
        SuperAG.................................. Disabled
        Radar.................................... Disabled
        Canopy................................... Disabled
        WiMax Mobile............................. Disabled
        WiMax Fixed.............................. Disabled
    Interference Device Merging Type............. normal
Additional Clean Air Settings:
    CleanAir Event-driven RRM State............. Enabled
    CleanAir Driven RRM Sensitivity............. Medium
    CleanAir Persistent Devices state........ Disabled 

Step 10 View the spectrum event-driven RRM configuration for the 802.11a/n or 802.11b/g/n network by entering this command:

show advanced {802.11a | 802.11b} channel

Information similar to the following appears:

Automatic Channel Assignment
  Channel Assignment Mode........................ AUTO
  Channel Update Interval........................ 600 seconds [startup]
  Anchor time (Hour of the day).................. 0
  Channel Update Contribution.................... SNI
  CleanAir Event-driven RRM option.............. Enabled
  CleanAir Event-driven RRM sensitivity...... Medium 
... 


Configuring Cisco CleanAir on an Access Point

This section describes how to configure Cisco CleanAir functionality on an individual access point using either the controller GUI or CLI.


Note See the "Configuring Cisco CleanAir on the Controller" section to enable or disable Cisco CleanAir functionality globally across the 802.11a/n or 802.11b/g/n network rather than for specific access points.


Using the GUI to Configure Cisco CleanAir on an Access Point

To configure Cisco CleanAir functionality for a specific access point using the controller GUI, follow these steps:


Step 1 Choose Wireless > Access Points > Radios > 802.11a/n or 802.11b/g/n to open the 802.11a/n (or 802.11b/g/n) Radios page.

Step 2 Hover your cursor over the blue drop-down arrow for the desired access point and click Configure. The 802.11a/n (or 802.11b/g/n) Cisco APs > Configure page appears (see Figure 13-3).

Figure 13-3 802.11a/n Cisco APs > Configure Page

The CleanAir Capable field shows whether this access point can support CleanAir functionality. If it can, go to the next step to enable or disable CleanAir for this access point. If the access point cannot support CleanAir functionality, you cannot enable CleanAir for this access point.


Note Currently, only Cisco Aironet 3500 series access points can be configured for Cisco CleanAir.



Note By default, the Cisco CleanAir functionality is enabled on the radios.


Step 3 Enable Cisco CleanAir functionality for this access point by choosing Enable from the CleanAir Status drop-down list. To disable CleanAir functionality for this access point, choose Disable. The default value is Enable. This setting overrides the global CleanAir configuration for this access point.

The Number of Spectrum Expert Connections text box shows the number of Spectrum Expert applications that are currently connected to the access point radio. Up to three active connections are possible.

Step 4 Click Apply to commit your changes.

Step 5 Click Save Configuration to save your changes.

Step 6 Click Back to return to the 802.11a/n (or 802.11b/g/n) Radios page.

Step 7 View the Cisco CleanAir status for each access point radio by looking at the CleanAir Status text box on the 802.11a/n (or 802.11b/g/n) Radios page.

The Cisco CleanAir status is one of the following:

UP—The spectrum sensor for the access point radio is currently operational (error code 0).

DOWN—The spectrum sensor for the access point radio is currently not operational because an error has occurred. The most likely reason for the error is that the access point radio is disabled (error code 8). To correct this error, enable the radio.

ERROR—The spectrum sensor for the access point radio has crashed (error code 128), making CleanAir monitoring nonoperational for this radio. If this error occurs, reboot the access point. If the error continues to appear, you might want to disable Cisco CleanAir functionality on the radio.

N/A—This access point radio is not capable of supporting Cisco CleanAir functionality. Currently, only Cisco Aironet 3500 series access point radios can be configured for Cisco CleanAir.


Note You can create a filter to make the 802.11a/n Radios page or the 802.11b/g/n Radios page show only access point radios that have a specific Cisco CleanAir status (such as UP, DOWN, ERROR, or N/A). This feature is especially useful if your list of access point radios spans multiple pages, preventing you from viewing them all at once. To create a filter, click Change Filter to open the Search AP dialog box, select one or more of the CleanAir Status check boxes, and click Find. Only the access point radios that match your search criteria appear on the 802.11a/n Radios page or the 802.11b/g/n Radios page, and the Current Filter parameter at the top of the page specifies the filter used to generate the list (for example, CleanAir Status: UP).



Using the CLI to Configure Cisco CleanAir on an Access Point

To configure CleanAir functionality for a specific access point using the controller CLI, follow these steps:


Step 1 Configure Cisco CleanAir functionality for a specific access point by entering this command:

config {802.11a | 802.11b} cleanair {enable | disable} Cisco_AP

Step 2 Save your changes by entering this command:

save config

Step 3 View the Cisco CleanAir configuration for a specific access point on the 802.11a/n or 802.11b/g/n network by entering this command:

show ap config {802.11a | 802.11b} Cisco_AP

Information similar to the following appears:

Cisco AP Identifier.............................. 0
Cisco AP Name.................................... CISCO_AP3500
...
Spectrum Management Information
        Spectrum Management Capable.............. Yes
        Spectrum Management Admin State.......... Enabled
        Spectrum Management Operation State...... Up
        Rapid Update Mode........................ Disabled
        Spectrum Expert connection............... Disabled
	 	Spectrum Sensor State................. Configured (Error code = 0) 


Note Refer to Step 7 in the "Using the GUI to Configure Cisco CleanAir on an Access Point" section for descriptions of the spectrum management operation states and the possible error codes for the spectrum sensor state.


Monitoring the Interference Devices

This section describes how to monitor the interference devices of the 802.11a/n and 802.11b/g/n radio bands using the controller GUI or CLI.


Note Only Cisco Aironet 3500 series access point radios can be configured for Cisco CleanAir.


Using GUI to monitor the Interference Device

To monitor the interference devices using the controller GUI, follow these steps:


Step 1 Choose Monitor > Cisco CleanAir > 802.11a/n or 802.11b/g > Interference Devices to open the CleanAir > Interference Devices page see (Figure 13-4).

Figure 13-4 CleanAir > Interference Device Page

This page shows the following information:

AP Name—The name of the access point where the interference device is detected.

Radio Slot #—Slot where the radio is installed.

Interferer Type—Type of the interferer.

Affected Channel—Channel that the device affects.

Detected Time—Time at which the interference was detected.

Severity—Severity index of the interfering device.

Duty Cycle (%)—Proportion of time during which the interfering device was active.

RSSI—Receive signal strength indicator (RSSI) of the access point.

DevID—Device identification number that uniquely identified the interfering device.

ClusterID—Cluster identification number that uniquely identifies the type of the devices.

Step 2 Click Change Filter to display the information about interference devices based on a particular criteria.

Step 3 Click Clear Filter to remove the filter and display the entire access point list.

You can create a filter to display the list of interference devices that are based on the following filtering parameters:

Cluster ID—To filter based on the Cluster ID, select the checkbox and enter the Cluster ID in the text box next to this field.

AP Name—To filter based on the access point name, select the checkbox and enter the access point name in the text box next to this field.

Interferer Type—To filter based on the type of the interference device, select the check box and select the interferer device from the options.

Select one of the interferer devices:

BT Link

MW Oven

802.11 FH

BT Discovery

TDD Transmit

Jammer

Continuous TX

DECT Phone

Video Camera

802.15.4

WiFi Inverted

WiFi Inv. Ch

SuperAG

Canopy

XBox

WiMax Mobile

WiMax Fixed

WiFi ACI

Unclassified

Activity Channels

Severity

Duty Cycle (%)

RSSI

Step 4 Click Find to commit your changes.

The current filter parameters are displayed in the Current Filter field.

Using GUI to monitor the Interference Device

Use these commands to monitor the interference devices for the 802.11a/n or 802.11b/g/n radio band.

View information for all of the interferers detected by a specific access point on the 802.11a/n or 802.11b/g/n radio band by entering this command:

show {802.11a | 802.11b} cleanair device ap Cisco_AP

Information similar to the following appears:

DC = Duty Cycle (%)
ISI = Interference Severity Index (1-Low Interference, 100-High Interference)
RSSI  = Received Signal Strength Index (dBm)
DevID = Device ID
 
   
No  ClusterID          DevID  Type 	 	 	 	 	 	 AP Name 			 	 	 	 	 ISI  RSSI 	 DC   Channel
--- ------------------ ------ ---------- --------------- ---- ----- ---- -------------
1   c2:f7:40:00:00:03  0x8001 DECT phone 	CISCO_AP3500 	1    -43 	 	 3 	 	 			149,153,157,161
2   c2:f7:40:00:00:51  0x8002 Radar		 	 	 	 		 	 CISCO_AP3500 	1    -81 		 		 2 	 	 153,157,161,165
3   c2:f7:40:00:00:03  0x8005 Canopy	 	 	 	 	 CISCO_AP3500 	2    -62	 	 	 2 	 	 153,157,161,165 

View information for all of the interferers of a specific device type on the 802.11a/n or 802.11b/g/n radio band by entering this command:

show {802.11a | 802.11b} cleanair device type type

Information similar to the following appears:

DC = Duty Cycle (%)
ISI = Interference Severity Index (1-Low Interference, 100-High Interference)
RSSI  = Received Signal Strength Index (dBm)
DevID = Device ID
  * indicates cluster center device 
 
No  ClusterID          DevID  Type 			 	 	 	 	 	 			AP Name 	 	 	 ISI  RSSI 	DC   Channel
--- ----------------- ------ -------------- ------------ ---- ----- --- --------------
1 	b4:f7:40:00:00:03 0x4185 DECT-like (26) CISCO_AP3500	1 	 	-58 	 	 	3 	 153,157,161,165
 
   

View a list of persistent sources of interference for a specific access point on the 802.11a/n or 802.11b/g/n radio band by entering this command:

show ap auto-rf {802.11a | 802.11b} Cisco_AP

Information similar to the following appears:

Number Of Slots.................................. 2
AP Name.......................................... AP1-L
MAC Address...................................... c4:7d:4f:3a:07:1e
  Slot ID........................................ 1
  Radio Type..................................... RADIO_TYPE_80211a
  Sub-band Type.................................. All
  Noise Information
    Noise Profile................................ PASSED
    Channel 34...................................  -97 dBm
    Channel 36...................................  -90 dBm
    Channel 38...................................  -97 dBm
Interference Information
    Interference Profile......................... PASSED
    Channel 34................................... -128 dBm @  0 % busy
    Channel 36................................... -128 dBm @  0 % busy
    Channel 38................................... -128 dBm @  0 % busy
    Channel 40................................... -128 dBm @  0 % busy
Load Information
    Load Profile................................. PASSED
    Receive Utilization.......................... 0 %
    Transmit Utilization......................... 0 %
    Channel Utilization.......................... 0 %
    Attached Clients............................. 0 clients
  Coverage Information
    Coverage Profile............................. PASSED
    Failed Clients............................... 0 clients
  Client Signal Strengths
    RSSI -100 dbm................................ 0 clients
    RSSI  -92 dbm................................ 0 clients
    RSSI  -84 dbm................................ 0 clients
Client Signal To Noise Ratios
    SNR    0 dB.................................. 0 clients
    SNR    5 dB.................................. 0 clients
    SNR   10 dB.................................. 0 clients
    SNR   15 dB.................................. 0 clients
Nearby APs
    AP c4:7d:4f:52:cf:a0 slot 1..................  -36 dBm on 149 (10.10.10.27)
    AP c4:7d:4f:53:1b:50 slot 1..................  -10 dBm on 149 (10.10.10.27)
Radar Information
  Channel Assignment Information
    Current Channel Average Energy............... unknown
    Previous Channel Average Energy.............. unknown
    Channel Change Count......................... 0
Last Channel Change Time..................... Mon May 17 11:56:32 2010
    Recommended Best Channel..................... 149
  RF Parameter Recommendations
    Power Level.................................. 7
    RTS/CTS Threshold............................ 2347
    Fragmentation Tnreshold...................... 2346
    Antenna Pattern.............................. 0
 
   
  Persistent Interference Devices
  Classtype Channel DC (%) RSSI (dBM) Last Update Time
---------------  -------  ------  ----------  ------------------------
  Canopy 	 	 	 149 	 	 	4 	 -63 	 	 	 	Tue May 18 03:21:16 2010
  All third party trademarks are the property of their respective owners.

Monitoring the Air Quality of Radio Bands

This section describes how to monitor the air quality of the 802.11a/n and 802.11b/g/n radio bands using the controller GUI or CLI.


Note Cisco WCS shows all of the reports related to Cisco CleanAir functionality. If you want to view all reports, use WCS and see the Cisco Wireless Control System Configuration Guide for instructions.


Using the GUI to Monitor the Air Quality of Radio Bands

To monitor the air quality of radio bands using the controller GUI, follow these steps:


Step 1 Choose Monitor > Cisco CleanAir > 802.11a/n or 802.11b/g >Air Quality Report to open the CleanAir > Air Quality Report page see (Figure 13-5).

Figure 13-5 CleanAir > AIr Quality Report Page

This page shows the air quality of both the 802.11a/n and 802.11b/g/n radio bands. Specifically, it shows the following information:

AP Name—The name of the access point that reported the worst air quality for the 802.11a/n or 802.11b/g/n radio band.

Radio Slot—The slot number where the radio is installed.

Channel—The radio channel where the air quality is monitored.

Minimum AQ—The minimum air quality for this radio channel.

Average AQ—The average air quality for this radio channel.

Interferer—The number of interferers detected by the radios on the 802.11a/n or 802.11b/g/n radio band.

DFSDynamic Frequency Selection. This indicates if DFS is enabled or not.


Using the CLI to Monitor the Air Quality of Radio Bands

Use these commands to monitor the air quality of the 802.11a/n or 802.11b/g/n radio band:

View a summary of the air quality for the 802.11a/n or 802.11b/g/n radio band by entering this command:

show {802.11a | 802.11b} cleanair air-quality summary

Information similar to the following appears:

AQ = Air Quality
DFS = Dynamic Frequency Selection 

AP Name 	 	 	 	Channel 	 Avg AQ 			 Min AQ 	 	Interferers 	DFS
-------------- 	-------- ------- 	------- ------------ ----
CISCO_AP3500				 36 	 	 	95 	 	70 		 0
CISCO_AP3500				 40      	 	 	93		75 	 	 0
CISCO_AP3500				 44      	 	 	95 		80 	 	 0
CISCO_AP3500				 48      	 	 	97 		75 	 	 0
CISCO_AP3500				 52      	 	 	98 		80 	 	 0
... 

View information for the 802.11a/n or 802.11b/g/n access point with the air quality by entering this command:

show {802.11a | 802.11b} cleanair air-quality

Information similar to the following appears:

AQ = Air Quality
DFS = Dynamic Frequency Selection 

AP Name 	 	 	 	Channel 	 Avg AQ			 	Min AQ 	 Interferers 	 DFS
-------------- --------- -------- --------- ------------ ------
CISCO_AP3500					1 	 	83 	 	 57 	 	 	 3 	 	 	5 

View air quality information for a specific access point on the 802.11a/n or 802.11b/g/n radio band by entering this command:

show {802.11a | 802.11b} cleanair air-quality Cisco_AP

Information similar to the following appears:

Slot Channel 	Avg AQ 	 Min AQ 		 Total Power (dBm) 	Total Duty Cycle (%)
---- ------- ------- 	------ 		 ----------------- 	--------------------
1	 140		 	100		100			-89				 	0
 
   
Interferer Power (dBm) Interferer Duty Cycle (%) Interferers DFS
---------------------- ------------------------- ----------- ---
-128							0                         0

Using the GUI to Monitor the Worst Air Quality of Radio Bands

To monitor the air quality of the 802.11a/n and 802.11b/g/n radio bands using the controller GUI, follow these steps:


Step 1 Choose Monitor > Cisco CleanAir > 802.11b/g >Worst Air-Quality to open the CleanAir > Worst Air Quality Report page (see Figure 13-6).

Figure 13-6 CleanAir > Worst Air Quality Report Page

This page shows the air quality of both the 802.11a/n and 802.11b/g/n radio bands. Specifically, it shows the following information:

AP Name—The name of the access point that reported the worst air quality for the 802.11a/n or 802.11b/g/n radio band.

Channel Number—The radio channel with the worst reported air quality.

Minimum Air Quality Index(1 to 100)—The minimum air quality for this radio channel. An air quality index (AQI) value of 100 is the best, and 1 is the worst.

Average Air Quality Index(1 to 100)—The average air quality for this radio channel. An air quality index (AQI) value of 100 is the best, and 1 is the worst.

Interference Device Count—The number of interferers detected by the radios on the 802.11a/n or 802.11b/g/n radio band.

Step 2 View a list of persistent sources of interference for a specific access point radio as follows:

a. Choose Wireless > Access Points > Radios > 802.11a/n or 802.11b/g/n to open the 802.11a/n (or 802.11b/g/n) Radios page.

b. Hover your cursor over the blue drop-down arrow for the desired access point radio and click CleanAir-RRM. The 802.11a/n (or 802.11b/g/n) Cisco APs > Access Point Name > Persistent Devices page appears. This page lists the device types of persistent sources of interference detected by this access point radio. It also shows the channel on which the interference was detected, the percentage of time that the interferer was active (duty cycle), the received signal strength (RSSI) of the interferer, and the day and time when the interferer was last detected.


Using the CLI to Monitor the Air Quality of Radio Bands

Use these commands to monitor the air quality of the 802.11a/n or 802.11b/g/n radio band:

View a summary of the air quality for the 802.11a/n or 802.11b/g/n radio band by entering this command:

show {802.11a | 802.11b} cleanair air-quality summary

Information similar to the following appears:

AQ = Air Quality
DFS = Dynamic Frequency Selection 

AP Name 	 	 	 	Channel 	 Avg AQ 			 Min AQ 	 	Interferers 	DFS
-------------- 	-------- ------- 	------- ------------ ----
CISCO_AP3500				 36 	 	 	95 	 	70 		 0
CISCO_AP3500				 40      	 	 	93		75 	 	 0
CISCO_AP3500				 44      	 	 	95 		80 	 	 0
CISCO_AP3500				 48      	 	 	97 		75 	 	 0
CISCO_AP3500				 52      	 	 	98 		80 	 	 0
... 

View information for the 802.11a/n or 802.11b/g/n access point with the worst air quality by entering this command:

show {802.11a | 802.11b} cleanair air-quality worst

Information similar to the following appears:

AQ = Air Quality
DFS = Dynamic Frequency Selection 

AP Name 	 	 	 	Channel 	 Avg AQ			 	Min AQ 	 Interferers 	 DFS
-------------- --------- -------- --------- ------------ ------
CISCO_AP3500					1 	 	83 	 	 57 	 	 	 3 	 	 	5 

View air quality information for a specific access point on the 802.11a/n or 802.11b/g/n radio band by entering this command:

show {802.11a | 802.11b} cleanair air-quality Cisco_AP

Information similar to the following appears:

Slot Channel 	Avg AQ 	 Min AQ 		 Total Power (dBm) 	Total Duty Cycle (%)
---- ------- ------- 	------ 		 ----------------- 	--------------------
1	 140		 	100		100			-89				 	0
 
   
Interferer Power (dBm) Interferer Duty Cycle (%) Interferers DFS
---------------------- ------------------------- ----------- ---
-128							0                         0
 
   

View information for all of the interferers detected by a specific access point on the 802.11a/n or 802.11b/g/n radio band by entering this command:

show {802.11a | 802.11b} cleanair device ap Cisco_AP

Information similar to the following appears:

DC = Duty Cycle (%)
ISI = Interference Severity Index (1-Low Interference, 100-High Interference)
RSSI  = Received Signal Strength Index (dBm)
DevID = Device ID
 
   
No  ClusterID          DevID  Type 	 	 	 	 	 	 AP Name 			 	 	 	 	 ISI  RSSI 	 DC   Channel
--- ------------------ ------ ---------- --------------- ---- ----- ---- -------------
1   c2:f7:40:00:00:03  0x8001 DECT phone 	CISCO_AP3500 	1    -43 	 	 3 	 	 			149,153,157,161
2   c2:f7:40:00:00:51  0x8002 Radar		 	 	 	 		 	 CISCO_AP3500 	1    -81 		 		 2 	 	 153,157,161,165
3   c2:f7:40:00:00:03  0x8005 Canopy	 	 	 	 	 CISCO_AP3500 	2    -62	 	 	 2 	 	 153,157,161,165 

View information for all of the interferers of a specific device type on the 802.11a/n or 802.11b/g/n radio band by entering this command:

show {802.11a | 802.11b} cleanair device type type

where type is one of the following:

802.11-fh—An 802.11 frequency-hopping device (802.11b/g/n only)

802.11-inv—A device using spectrally inverted Wi-Fi signals

802.11-nonstd—A device using nonstandard Wi-Fi channels

802.15.4—An 802.15.4 device (802.11b/g/n only)

all—All interference device types (this is the default value)

bt-discovery—A bluetooth discovery (802.11b/g/n only)

bt-link—A bluetooth link (802.11b/g/n only)

canopy—A canopy device

cont-tx—A continuous transmitter

dect-like—A digital enhanced cordless communication (DECT)-compatible phone

jammer—A jamming device

mw-oven—A microwave oven (802.11b/g/n only)

radar—A radar device (802.11a/n only)

superag—An 802.11 SuperAG device

tdd-tx—A time division duplex (TDD) transmitter

video camera—An analog video camera

wimax-fixed—A WiMAX fixed device

wimax-mobile—A WiMAX mobile device

xbox—A Microsoft Xbox (802.11b/g/n only)

Information similar to the following appears:

DC = Duty Cycle (%)
ISI = Interference Severity Index (1-Low Interference, 100-High Interference)
RSSI  = Received Signal Strength Index (dBm)
DevID = Device ID
  * indicates cluster center device 
 
No  ClusterID          DevID  Type 			 	 	 	 	 	 			AP Name 	 	 	 ISI  RSSI 	DC   Channel
--- ----------------- ------ -------------- ------------ ---- ----- --- --------------
1 	b4:f7:40:00:00:03 0x4185 DECT-like (26) CISCO_AP3500	1 	 	-58 	 	 	3 	 153,157,161,165
 
   

View a list of persistent sources of interference for a specific access point on the 802.11a/n or 802.11b/g/n radio band by entering this command:

show ap auto-rf {802.11a | 802.11b} Cisco_AP

Information similar to the following appears:

Number Of Slots.................................. 2
AP Name.......................................... CISCO_AP3500
...
Persistent Interferers
  Classtype                  Channel  DC (%)  RSSI (dBm)  Last Update Time
  -------------------------  -------  ------  ----------  -------------------------
	802.11FH							149		3		-58			Thu Jan 1 00:20:34 2009
	Radar							153		2		-81			Thu Jan 1 00:20:35 2009
	Continuous Transmitter				 	 	 	157		2		-62			Thu Jan 1 00:20:36 2009
	...
    All third party trademarks are the property of their respective owners.
 
   

Configuring a Spectrum Expert Connection

To obtain detailed spectrum data that can be used to generate RF analysis plots similar to those provided by a spectrum analyzer, you can configure a Cisco CleanAir-enabled access point to connect directly to a Microsoft Windows XP or Vista PC running the Spectrum Expert application (referred to as a Spectrum Expert console). You can initiate the Spectrum Expert connection semi-automatically from WCS or by manually launching it from the controller. This section provides instructions for the latter.


Note See the Wireless Control System Configuration Guide, Release 7.0, for information on initiating a Spectrum Expert connection using WCS.



Note Spectrum Expert (Windows XP laptop client) and AP should be pingable, otherwise; it will not work.


To configure a Spectrum Expert, follow these steps:


Step 1 Prior to establishing a connection between the Spectrum Expert console and the access point, make sure that IP address routing is properly configured and the network spectrum interface (NSI) ports are open in any intervening firewalls.


Note The following NSI ports are required: TCP 37540 for 2.4 GHz (slot 0) and TCP 37550 for 5 GHz (slot 1) with the access point as the server.


Step 2 Make sure that Cisco CleanAir functionality is enabled for the access point that will be connected to the Spectrum Expert console.

Step 3 Configure the access point for SE-Connect mode using the controller GUI or CLI.


Note The SE-Connect mode is set for the entire access point, not just a single radio. However, the Spectrum Expert console connects to a single radio at a time.


If you are using the controller GUI, follow these steps:

a. Choose Wireless > Access Points > All APs to open the All APs page.

b. Click the name of the desired access point to open the All APs > Details for page (see Figure 13-7).

Figure 13-7 All APs > Details For Spectrum

c. Choose SE-Connect from the AP Mode drop-down list. This mode is available only for access points that are capable of supporting Cisco CleanAir functionality. For the SE-Connect mode to appear as an available option, the access point must have at least one spectrum-capable radio in the Enable state.

d. Click Apply to commit your changes.

e. Click OK when prompted to reboot the access point.

If you are using the controller CLI, follow these steps:

a. To configure the access point for SE-Connect mode, enter this command:

config ap mode se-connect Cisco_AP

b. When prompted to reboot the access point, enter Y.

c. To verify the SE-Connect configuration status for the access point, enter this command:

show ap config {802.11a | 802.11b} Cisco_AP

Information similar to the following appears:

Cisco AP Identifier.............................. 0
Cisco AP Name.................................... CISCO_AP3500
...
Spectrum Management Information
        Spectrum Management Capable.............. Yes
        Spectrum Management Admin State.......... Enabled
        Spectrum Management Operation State...... Up
        Rapid Update Mode........................ Disabled
        Spectrum Expert connection............... Enabled
	 	Spectrum Sensor State.................. Configured (Error code = 0) 

Step 4 On the Windows PC, access the Cisco Software Center from this URL:

http://www.cisco.com/cisco/software/navigator.html

Step 5 Click Wireless > Cisco Spectrum Intelligence > Cisco Spectrum Expert > Cisco Spectrum Expert Wi-Fi, and then download the Spectrum Expert 4.0 executable (*.exe) file.

Step 6 Run the Spectrum Expert application on the PC.

Step 7 When the Connect to Sensor dialog box appears, enter the IP address of the access point, choose the access point radio, and enter the 16-byte network spectrum interface (NSI) key to authenticate. The Spectrum Expert application opens a TCP/IP connection directly to the access point using the NSI protocol.


Note On the controller GUI, the NSI key appears in the Network Spectrum Interface Key field (below the Port Number field) on the All APs > Details for page. To view the NSI key from the controller CLI, enter the show {802.11a | 802.11b} spectrum se-connect Cisco_AP command. This parameter is shown only for CleanAir capable access points for only Local, HREAP, and SE Connected mode.


When an access point in SE-Connect mode joins a controller, it sends a Spectrum Capabilities notification message, and the controller responds with a Spectrum Configuration Request. The request contains the 16-byte random NSI key generated by the controller for use in NSI authentication. The controller generates one key per access point, which the access point stores until it is rebooted.


Note You can establish up to three Spectrum Expert console connections per access point radio. The Number of Spectrum Expert Connections text box on the 802.11a/n (or 802.11b/g/n) Cisco APs > Configure page of the controller GUI shows the number of Spectrum Expert applications that are currently connected to the access point radio.


Step 8 Verify that the Spectrum Expert console is connected to the access point by selecting the Slave Remote Sensor text box in the bottom right corner of the Spectrum Expert application (see Figure 13-8). If the two devices are connected, the IP address of the access point appears in this text box.

Figure 13-8 Spectrum Expert Application

Step 9 Use the Spectrum Expert application to view and analyze spectrum data from the access point.


Note See the Cisco Spectrum Expert Users Guide, Release 4.0, for information on using the Spectrum Expert application.