AirMagnet is privately held, with over 80 employees and 6,000 enterprise customers, including 75 of the Fortune 100. Its sales support is quite impressive for a fairly young firm, with over 200 sales, training, and support partners worldwide in 114 countries. Today, the company is considered a leader in security, performance, and compliance solutions for wireless LANs.

The AirMagnet solutions are a critical layer between the wireless LAN infrastructure and mobility applications, ensuring that the wireless network is secure, complies with internal and external policies and regulation, and delivers at the performance levels required. The company's innovative products include AirMagnet Enterprise, the leading 24x7 WLAN security and performance management solution, and the AirMagnet Laptop Analyzer. Other products provide WLAN site survey and design, RF interference detection, remote diagnostics, and the world's first voice over WiFi analysis solution.

AirMagnet claims that its VoFi Analyzer 3.5, announced in December 2007, is the industry's only purpose-built system for troubleshooting voice-over-WLAN problems that occur in the field. Typical problems in these environments can come from a number of sources, including typical network failures, the RF environment, inappropriate QoS settings, the IP-PBX, or the telephones themselves. Such a diverse mixture of problem areas can make these voice problems particularly challenging and time consuming to diagnose.

For VoFi deployments, it is essential to gather as much information regarding a voice call as possible—from end to end—so problems can be quickly isolated and resolved. AirMagnet's solution to this end-to-end complexity is a specifically adapted version of their AirWISE analysis engine that automatically diagnoses over 60 types of wireless call problems. This AirWISE engine constantly captures and analyzes live voice traffic, to provide immediate answers to voice-over-WLAN problems.

A wide range of such problems can be addressed, including QoS problems, roaming issues, power-save problems, overloaded devices, fragmentation, one-way audio, telephone failures, and many more. Information is collected and integrated from the connection, device, and server (air, phone and wire), providing valuable insight into the state of voice deployments. More importantly, these tests can be performed on a fully encrypted wireless network.

Here's how it works. First, the VoFi Analyzer directly samples the wireless traffic as it travels through the air. This delivers an unbiased, third party perspective on the quality between a given phone and the wireless infrastructure, as well as a simultaneous view into both sides of the call (access point-to-phone and phone-to-access point). Next, the product integrates with leading phones to directly collect Syslog messages, giving crucial insight into call quality at the device level. Finally, the VoFi Analyzer integrates with leading VoIP servers to provide a "wired" perspective on the connection, letting IT managers easily see the call tear-down details. Another unique capability of VoFi Analyzer is its ability to deliver complete analysis of fully encrypted wireless voice traffic, allowing IT managers to troubleshoot connection issues without exposing enterprise networks.

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The AirMagnet VoFi Analyzer displays the network operations in terms of calls and call quality. It scans all 802.11a/b/g devices, distinguishes between voice and data traffic, and automatically scores every call in terms of its WiR-Value and WiMOS Score, based upon a variety of packet metrics, including loss rate and jitter. The system independently scores and tracks both sides of the call, allowing users to distinguish problems that are rooted on one side of the call. Each call is color-coded according to call quality, making it easy to visualize telephones or calls having problems. This level of analysis provides a full history of all calls on the network, and quickly reveals problems that are tied to a particular telephone, channel, or given period of time (see figure).

The VoFi Analyzer is available in both a standard version, and the VoFi Analyzer PRO, which can integrate with voice solutions from Cisco, SpectraLink and Vocera, enabling the analyzer to retrieve end-user information such as the name and telephone number, receive telephone-generated diagnostic information, and more. Both versions run under Windows XP, and support a large number of wireless interface adapters.

Further details on the AirMagnet architecture and products can be found at http://airmagnet.com/. Our next tutorial will continue our examination of vendors' network management architectures.