CleanAir is a passive technology that
does not affect the normal operation of Wi-Fi networks. There is no inherent
difference between a CleanAir deployment and a mesh deployment.
Locating a non-Wi-Fi device
has a lot of variables to consider. Accuracy increases with power, duty cycle,
and the number of channels hearing the device. This is advantageous because
higher power, higher duty cycle, and devices that impact multiple channels are
considered to be severe with respect to interference to networks.
Note |
There is no guarantee of
accuracy for location of non- Wi-Fi devices.
|
There are a lot of variables
in the world of consumer electronics and unintentional electrical interference.
Any expectation of accuracy that is derived from current Client or Tag location
accuracy models does not apply to non-Wi-Fi location and CleanAir features.
Important notes to consider:
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CleanAir mesh AP supports the
assigned channel only.
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Band Coverage is implemented
by ensuring that channels are covered.
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The CleanAir mesh AP can hear
very well, and the active cell boundary is not the limit.
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For Location solutions, the
RSSI cutoff value is –75 dBm.
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A minimum of three quality
measurements is required for location resolution.
In most deployments, it is
difficult to have a coverage area that does not have at least three APs nearby
on the same channel in the 2.4-GHz band. In locations where there is minimal
density, while the location resolution is likely not supported, the active user
channel is protected.
Deployment considerations are
dependent upon planning the network for desired capacity and ensuring that you
have the correct components and network paths in place to support CleanAir
functions. RF proximity and the importance of RF Neighbor Relations cannot be
understated. It is important to keep in mind the PMAC and the merging process.
If a network does not have a good RF design, the neighbor relations is
affected, which in turn affects CleanAir performance.
The AP Density
recommendations for CleanAir remain the same as normal mesh AP deployment.
Location resolution in the
Outdoors is to the nearest AP. Devices are located near the AP which is
physically closest to the device. It is advisable to assume closest AP
resolution.
It is possible to deploy a
few 1530 APs (non-CleanAir) with an installation that consists of 1552 APs and
1572 APs (CleanAir). This deployment can work from a client and coverage
standpoint as these access points are fully interoperable with each other. The
complete CleanAir functionality depends on all access points being CleanAir
enabled. Detection can be affected, and mitigation is not recommended.
A CleanAir AP actively
serving clients can only monitor the assigned channel that it is serving. In an
area where you have multiple access points serving clients in close proximity,
the channels being served by CleanAir access points can drive CleanAir
features. Legacy non-CleanAir access points rely on RRM, and mitigate
interference issues, but not report the type and severity as CleanAir access
points do to the system level.
For more information about
mixed systems, see
http://www.cisco.com/en/US/products/ps10315/products_tech_note09186a0080b4bdc1.shtml