July 11, 2007, 3:02 PM — AirMagnet is claiming to be the first to provide complete end-to-end visibility into voice-over-WLAN deployments, because it collects and correlates data from the handset and the call-server, as well as data from the wireless link.
Its new VoFi Analyzer Pro 3.0 software can also analyze calls on encrypted networks without decrypting the voice traffic, and it can track calls as they roam across access points and WLAN channels to help identify connection problems with moving handsets.
"AirMagnet is dramatically raising the standard for voice analysis and providing a product that delivers an unparalleled level of insight into voice over wireless LANs," claimed Chris Roeckl, AirMagnet's marketing VP. "Our new approach to gathering voice application information, combined with our ability to analyze information on encrypted networks, makes this an extremely powerful tool for ensuring voice over wireless LAN call quality in the enterprise."
He said that direct sampling of wireless voice traffic provides the third-party perspective on the quality between the phone and the wireless infrastructure, while pulling in call-server and handset logs gives a simultaneous view into the other legs of the call, ie. access point to phone and phone to access point.
For now the AirMagnet software only supports a limited range of hardware -- certain Spectralink phones, Cisco Call Manager and Vocera's call servers.
Several other tools offer voice-over-WLAN (VoWLAN) analysis, including OmniPeek VX from WildPackets and VeriWave's WaveTest. Neither of those collects server or handset data, though.
Roeckl said that the extra data is important when it comes to understanding and fixing connection or call quality issues, as the wireless network is not the only possible source of problems here.
However, WildPackets CTO Scott Haugdahl questioned the value of the server and client data, especially given VoFi Analyzer's limited hardware support.
"It's an interesting idea, but it comes down to how good the data is and how well the tools correlate it," he said. "Do you need syslog records from the phone? We can tell an awful lot from the flow data."
He pointed out too that collecting data from the phone and the call manager requires access to both, something that could be problematic on large networks.
"You have to get access to the data remotely, and Cisco locks those devices down pretty tightly," he said. "So we try to do as much as possible passively."
