AirMedic Overview. Live spectrum stats by channel. Real-time graphs FFT, Duty Cycle, (WiFi plots optional) APs listed by SSID or Channel

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1 AirMedic Overview AirMedic is a brand new WiFi troubleshooting and optimization tool from AirMagnet that provides a clear, concise view into your most common wireless problems. At its core, AirMedic is a revolutionary new WiFi spectrum analyzer. Instead of requiring an external PC card or dongle, which can easily be lost or broken, AirMedic leverages the integrated adapter in any Intel Centrino 2 equipped notebook. However, the true power of the AirMedic software lies not in this new design, but in how it helps you zero in on wireless problems quickly and easily. In addition to professional spectrum analysis AirMedic lets you plug in any supported WiFi card for additional WiFi traffic analysis to supplement your troubleshooting. This means that for the first time, you can easily and directly connect RF information to the real performance of your wireless devices. The software brings everything together in a single, clean interface that ensures that you can easily see the information that you need without digging through pages of data. This document will introduce you to AirMedic interface and features and provide some basic examples of how to you use it to troubleshoot your network. AirMedic Layout AirMedic is organized around a single powerful screen. This is to ensure that all the information you need can be aligned into a single view instead of having to go back and forth between pages in the application. The interface is divided into two main sections the left side of the interface provides overview tables of spectrum and WiFi data in terms of channels, while the larger right side of the screen displays the live graphs, plots and charts. Live spectrum stats by channel Real-time graphs FFT, Duty Cycle, (WiFi plots optional) APs listed by SSID or Channel Device counts by channel

2 Now we will review each of the various panels and how to use them. The top left section provides a table of the most important spectrum stats organized by WiFi channel. You can click on a particular channel in the table and the application will highlight the channel in the spectrum graphs on the right. Simply, click the channel again to un-highlight the channel. This is a helpful tool to keep in mind if you are troubleshooting problems on a particular channel. Just below the channel summary is an optional WiFi section that can be enabled by using an additional WiFi adapter. Refer to for a list of Wi-Fi adapters that are supported to provide the additional Wi-Fi analysis. When enabled, this section will provide a list of all the APs detected in the environment. The APs can be grouped either by SSID or by channel using the drop down menu above the frame. By checking the box next to an SSID or device, you can see an estimated curve of that device overlayed on the spectrum density plot to the right. This is a powerful tool to help distinguish between RF energy coming from your APs versus non-wifi sources of interference. Troubleshooting Tips: If you are seeing problems on a particular channel use this feature to see what APs are operating on the channel and how strong they are. Is there an AP that is much stronger than the one you are trying to use? If so, this can cause co-channel interference that can rob your AP of performance. Are there

3 multiple APs with similar signal strengths? This can also lead to competition or excessive client roaming. We can also use this feature to identify energy in the spectrum that doesn t tie back to a WiFi device. Simply highlight all the devices and see which areas of spectrum plot don t correspond to a device and you can see which areas are impacted by non-wifi interference. Below the AP list and at the bottom left of the screen is a table of all WiFi devices in the environment. This table includes client stations and phones in addition to APs. This again is very helpful in helping to determine the type of problem you are having. If all of your end-users are clumped on a single channel you may be experiencing an overloaded even the network as a whole is underutilized. Charts, Plots and Graphs The right side of the screen constitutes the meat of the application and gives us access to 14 sets of data focused on troubleshooting. By default, the application shows Spectrum FFT, Spectrum Density and Top APs Signal graphs. To select a different graph, click the name of the graph and choose from the list provided. Each chart or graph is customizable allowing you to choose the information you want to display and control resolution settings. The configuration options can be accessed using the button at the top right of the chart.

4 Most charts also provide additional information by using tool tips. For example, you can always see the actual frequency of a point on the FFT by hovering the mouse over the point of interest. Another helpful use of this tool can be seen in the WiFi screens. The chart below shows the 3 strongest APs on a particular channel. By hovering the mouse over the color-coded sections of the chart, we can see the name of the AP and its critical information.

5 Notes on Key Screens Here we will cover some of the key values of each chart. Refer to the product release notes and documentation for a description of charts that are not covered here. The FFT is the bedrock view of any spectrum analyzer. This view shows a real-time view into the spectrum allowing you to see real-time waveforms. For example, if you see a jagged saw tooth pattern with equally spaced peaks in the FFT, that is the telltale sign of a Bluetooth device or some similar frequency hopping device. Spectrum Density provides a different view of the spectrum, by showing the popularity of certain signal strengths at a particular part of the spectrum. This allows you to see the waveforms of devices that may not be transmitting all the time and thus may be hard to catch in the real-time FFT plot. Note the even domed curve of an AP highlighted on channel 1.

6 WiFi Devices shows configuration information for the detected WiFi devices in the environment including the security settings on each. You can use this section to help identify devices that are a part of your network from neighbors or unapproved APs. CRC and Retry lets immediately see APs that are having problems communicating. This lets you start troubleshooting from the top down instead of looking at spectrum first, you can find the APs with the highest percentage of retry or CRC packets and then use the other plots to identify whether it is due to WiFi co-channel interference ( signal strength by channel), spectrum interference (FFT, Spectrum Density, Spectrogram), or overloaded devices (channels by speed). Conclusion We hope this document has helped to introduce you to the AirMedic application and the many ways that it can be used. At this point we encourage you to begin your own experiments to see how you can use the tool to solve problems in your environment. As always we are eager for your feedback including potential improvements for the product, problems and most importantly how you used AirMedic to solve problems. Please send all feedback and any recommendations on the content of this document to dilipadvani@airmagnet.com

7 About AirMagnet AirMagnet Inc. is the leader in security, performance and compliance solutions for wireless LANs. The company's innovative products include AirMagnet Enterprise, the leading 24x7 WLAN security and performance management solution, and AirMagnet WiFi Analyzer which is known as the "de facto tool for wireless LAN troubleshooting and analysis." Other products provide WLAN site survey and design, RF interference detection, remote diagnostics, and the world's first voice over WiFi analysis solution. AirMagnet has more than 8,200 customers worldwide, including 75 of the Fortune 100. The company, based in Sunnyvale, Calif., has offices worldwide. Corporate Headquarters 830 E. Arques Ave. Sunnyvale, CA United States Tel: Fax: EMEA Headquarters 6-9 The Square Stockley Park Uxbridge Middlesex UB11 1FW United Kingdom Tel: Fax: