Cisco 8821, Manual

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Cisco Wireless IP Phone 8821 and 8821-EX Wireless LAN Deployment Guide
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Wireless LAN Design
The following network design guidelines must be followed in order to accommodate for adequate coverage, call capacity and
seamless roaming for the Cisco Wireless IP Phone 8821 and 8821-EX.
802.11 Network
Use the following guidelines to assist with deploying and configuring the wireless LAN.
5 GHz (802.11a/n/ac)
5 GHz is the recommended frequency band to utilize for operation of the Cisco Wireless IP Phone 8821 and 8821-EX.
In general, it is recommended for access points to utilize automatic channel selection instead of manually assigning channels to
access points.
If there is an intermittent interferer, then the access point or access points serving that area may need to have a channel statically
assigned.
The Cisco Wireless IP Phone 8821 and 8821-EX support Dynamic Frequency Selection (DFS) and Transmit Power Control
(TPC) from 802.11h, which are required when using channels operating at 5.260 - 5.720 GHz, which are 15 of the 24 possible
channels.
Need to ensure there is at least 20 percent overlap with adjacent channels when deploying the Cisco Wireless IP Phone 8821
and 8821-EX in an 802.11a/n/ac environment, which allows for seamless roaming. For critical areas, it is recommended to
increase the overlap (30% or more) to ensure that there can be at least 2 access points available with -67 dBm or better, while
the Cisco Wireless IP Phone 8821 and 8821-EX also meet the access point’s receiver sensitivity (required signal level for the
current data rate).