Cisco Cisco Catalyst 6000 Multilayer Switch Feature Card MSFC2 White Paper
© 2013 Cisco and/or its affiliates. All rights reserved. This document is Cisco Public Information.
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The closer that the APs and clients can be to one another, the higher the spectral efficiency will be. If the APs and
clients must be operated at a distance due to architectural requirements, use of directional antennas will improve
the cell isolation, and reduce the power required for Tx in both directions.
The foremost failure in most high-density designs is not enough APs or channels. The secondary reason for failure
in most high-density designs is poor channel isolation; too many APs and channels in the space.
Cisco Unified Wireless Network Best Practices
The following sections cover some of the basic design decisions that should be considered and why they are
important. It is understood that not all of these recommendations will be possible in a legacy design. These points
are highly recommended for the support of a high-density WLAN design. The market and the technology continue
to evolve rapidly, and these recommendations will also continue to evolve.
Information in this section is not intended to replace the recommended design guides for campus and WLAN
deployments referenced elsewhere within this document. This is a partial list of considerations that pertain
specifically to high-density design considerations. Local Cisco sales teams or Cisco partners are the best resource
for questions concerning the goals and requirements of a particular WLAN design.
Pre-Deployment Site Inspection and Validation
Prior to deploying a WLAN, the site should be evaluated based on the following:
RF Interference
●
The site may have pre-existing WLANs as part of the same RF network.
●
There may be nearby WLANs that are not part of the existing RF network.
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There may be nearby sources of microwaves and/or surveillance cameras or other forms of non Wi-Fi
interference.
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There will most likely be Bluetooth.
●
The WCS and the WLAN controller provide accurate reporting on CCI conditions.
●
Cisco CleanAir provides in-depth interference analysis and monitoring 7x24.
Site Survey
●
Visually inspect the site for multipath potential and placement options for the APs and antennas.
●
Walking the site using a good survey tool is highly recommended. Using a Live RF tool such as AirMagnet
Surveyor will enable an evaluation of RF propagation and the ability to actively transmit data and evaluate
range and data rate coverage.
WLAN Design Tools
Providing a high-density WLAN is clearly a challenging project but these networks are increasingly being
deployed. Knowing what is in place and using a spectrum today are essential steps. Knowing where a spectrum is
going at installation is critical. Maintaining the environment also requires regular observation and occasional
troubleshooting, as WLAN dynamics have a tendency to change over time. Most of the management concerns
can be eliminated by implementing Cisco WCS, but the importance of the site survey during the planning and
deployment cannot be emphasized enough. The need for good tools and accurate assessments increase with the
density of the deployment. There is a fine line between interference and usable spectrum in a high-density WLAN.