Rugged Environments - Cisco 8821 Manual

Note: Some environments may require that a lower data rate be enabled due to use of legacy clients, environmental factors or
maximum range is required.
Set only the lowest data rate enabled as the single mandatory / basic rate. Multicast packets will be sent at the highest
mandatory / basic data rate enabled.
Note that capacity and throughput are reduced when lower rates are enabled.

Rugged Environments

When deploying the Cisco Wireless IP Phone 8821 and 8821-EX in a rugged environment (e.g. manufacturing, warehouse,
retail), additional tuning on top of the standard design recommendations may be necessary.
Below are the key items to focus on when deploying a wireless LAN in a rugged environment.
Access Point and Antenna Selection
For rugged environments, it is recommended to select an access point platform that requires external antennas (e.g.
Cisco 1602e, 2602e, 3502e, 3602e, and 3702e Series Access Points). It is also important to ensure an antenna type is
selected which can operate well in rugged environments.
Access Point Placement
It is crucial that line of sight to the access point's antennas is maximized by minimizing any obstructions between the
Cisco Wireless IP Phone 8821 or 8821-EX and the access point. Ensure that the access point and/or antennas are not
mounted behind any obstruction or on or near a metal or glass surface.
If access points with integrated internal antennas are to be used in some areas (other than the W series), then it is
recommended to mount those access points on the ceiling as they have omni-directional antennas and are not designed
to be wall mounted.
Frequency Band
As always, it is recommended to use 5 GHz. Use of 2.4 GHz, especially when 802.11b rates are enabled, may not work
well.
For the 5 GHz channel set, it is recommended to use a 8 or 12 channel plan only; disable UNII-2 extended channels if
possible.
Data Rates
The standard recommended data rate set may not work well if multipath is present at an elevated level.
Therefore, it is recommended to enable lower data rates (e.g. 6 Mbps) to operate better in such an environment.
If using for voice only, then data rates above 24 Mbps can be disabled to increase first transmission success. If the
same band is also used for data, video or other applications, then is suggested to keep the higher data rates enabled.
Transmit Power
Due to the potential of elevated multipath in rugged environments, the transmit power of the access point and Cisco
Wireless IP Phone 8821 and 8821-EX should also be restricted. This is more important if planning to deploy 2.4 GHz
in a rugged environment.
If using auto transmit power, the access point transmit power can be configured to use a specified range (maximum and
minimum power levels) to prevent the access point from transmitting too hot as well as too weak (e.g. 5 GHz maximum
of 16 dBm and minimum of 11 dBm).
The Cisco Wireless IP Phone 8821 and 8821-EX will utilize the access point's current transmit power setting to
determine what transmit power it uses for transmitted frames when DTPC is enabled in the access point's
configuration.
Fast Roaming
Cisco Wireless IP Phone 8821 and 8821-EX Wireless LAN Deployment Guide
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