Apr 02, 2010
While many forms of wireless-LAN assurance and verification tools have become available over the past decade or so of the history of the WLAN and Wi-Fi, one of the last to be addressed is the ability to examine activity at the physical layer(PHY) � in other words, to look at what�s happening in the air itself, what we call spectral assurance (SA). SA is particularly important not just because the frequencies used by WLANs are unlicensed, and thus subject to arbitrary radio signals and interference, but rather because WLANs are now mission-critical in so many applications,
serving as primary and even default access, and the need to detect and remediate spectrum-related challenges has become equally vital.
The device used to address this challenge is called a spectrum analyzer, and, with the initial availability of Cisco�s notebook-PC-based Spectrum Expert in 2005, a low-cost but highly-effective tool was finally available to network operations staffs everywhere. But a new challenge has emerged: as wireless LANs have grown in importance and coverage, the ad hoc approach to spectrum analysis, what we call the �walking around� (�WAM�) model of operation enabled by mobile spectrum analyzers, while still valuable, is less than optimal. With recent introduction of Cisco�s CleanAir product line, the CIM strategy is now a reality, leading to some very interesting questions about the total cost of ownership of such an approach � the subject of this White Paper.