Extreme Networks

CTS 107: What’s The Purpose of Cisco CleanAir

Are you fully utilizing CleanAir to it’s maximum capability? We dive into the intricacies of Cisco CleanAir.

This episode is sponsored by Metageek

Sponsored by Metageek

Cisco CleanAir

Download your free CleanAir Reference Sheet PDF

The earliest Cisco WLC version where Cisco CleanAir was released dates back to the 7.0 days. Sometime around the year 2010. Cisco CleanAir is always on within an AP, granted if it is Enabled in the WLC. There is a Spectrum Analysis Engine (SaGE) chip built into the AP. This is important to know because it doesn’t prevent the AP from serving clients. SaGE works alongside the Wi-Fi chip. There is no affect to client throughput or traffic.

To enhance Cisco RRM’s features, CleanAir plays a critical role in allowing RRM to change channels if persistent interference is detected. CleanAir will field the appropriate algorithms to help the WLC make changes to improve an environment.

Cisco CleanAir produces two important elements:

  • Interference Device Report
  • Air Quality Index

The Interference Device Report (IDR) provides information on detected interference. It will provide a class type, what band the interference was detected on and on what channel(s), the severity of the interference, it’s duty cycle, and the interference signature.

The Air Quality Index (AQI) provides a quality score, from 0 – 100%, with 100% being good. The index will display total channel power, total channel duty cycle, the power of the interferer and total interference duty cycle.

A benefit of using Cisco CleanAir is having the ability to troubleshoot the shared spectrum remotely and without any additional hardware. A CleanAir supported access point can be utilized for this purpose. Some things to keep in mind when using your CleanAir access point for troubleshooting interference:

There are three modes:

  • Local – The AP will continue to serve clients on its operating channel. But any spectrum monitoring is performed on that channel only.
  • Monitor – The AP doesn’t server any clients but provides full time scanning.
  • Spectrum Expert Connect – This is a dedicated spectrum sensor and doesn’t serve any clients.

In times when the best response is to use technical support hands to troubleshoot the issue, having a method of automatically mitigating an interference issue can be highly beneficial. It can cut time to resolution down and react faster than a support team that is reactionary.

What we’d like to see from CleanAir is the ability to tell an administrator whether any action needs to be performed. While interference and air quality is determined on any given channel, does it even matter? Are any users impacted negatively? A smarter system would be able to detect interference and provide exactly which users are having issues directly related to this interferer and what kind of impact that is. And a step further would be to automatically adjust the system to fix the problem.

We’ve included some images of Cisco CleanAir in action from within Spectrum Expert and Metageek Chanalyzer.

Links and Resources and News


We are giving away CTS apparel of your choice. Either a CTS shirt or sweater! To enter, do the following:

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  4. Let us know what was your most recent interference encounter in the comments below
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CTS 092: Update From Extreme Networks

Mike Leibovitz joins the show to speak about exciting times at Extreme Networks, what they’ve done with acquisitions and where they are headed, Extreme Wi-Fi updates with AC Wave 2, and more.

Mike Leibovitz of Extreme Networks

10 years Mike has been at Extreme Networks. Since 2007/2008 he has focused primarily on Wi-Fi. He has done his fair share of work from sales enginneer, switching, routing, and voice. The way Mike Leibovitz got into Wi-Fi was through a project. Now he holds Director of Product Strategy role for wireless projects.

There are two Wi-Fi product lines that Extreme Networks carries. One is for the campus market and the other is for distributed enterprise. In a campus environment, you’ll want more with the control plane for things such as layer 3 roaming and centralization of traffic.

Extreme Network’s flagship access point is a Wave 2 4×4 with a tri-radio. It works with their security solution, AirDefense.

A key thing to know about is the Flow based characteristics which splits the data plane. Analytics runs on top and then you have flow based rules.

This episode on Extreme Networks goes into so much more information. Listen to hear more about:

  • Beyond RF
  • Security
  • 802.11ax

Links and Resources

CTS 091 – New York City – A Connected City

New York City flipped the switch and enabled Wi-Fi and cellular network in all underground subway stations. Jeremy Ward, of Transit Wireless, joins us to talk about this large scale project and what it took to do it.

This episode is sponsored by Metageek

Sponsored by Metageek

New York City – A Connected City

Jeremy Ward title slide

Jeremy Ward of Transit Wireless joins us on the show to talk about getting the underground subway stations connected with Wi-Fi and cellular connectivity. The project includes 120 miles of fiber optic cabling, 4,000 cellular antennas, and 5,000 Wi-Fi access points. The network supports the users who use mass transportation every day, public safety, transit communications, and over 3,000 Help Point kiosks for riders.

Jeremy discusses the challenges that came up with deploying a solution like this in an underground subway station. Many challenges to Wi-Fi make planning very important. There are issues from the environment, including:

  • Noise
  • Dirt
  • Heat
  • Cold weather
  • Brake dust from the trains
  • Pressure washers
  • Vandalism
  • and RF

It’s very possible to get RF reflected from moving trains!

Placement can be tough to tackle underground. One of the important things to consider is vandalism. Jeremy’s team has tested different enclosures by taking a baseball bat to them!

Other topics discussed on this episode:

  • Design requirements
  • User traffic
  • Hardware considerations
  • Extreme Networks
  • Motorola
  • Wireless LAN Controllers
  • Security
  • Analytics

New York City Subway Wi-Fi Stats

Statistics from NYC Subway Wi-Fi

Links & Resources