Cisco Cisco IP Phone 8841 Guía De Diseño
Cisco IP Phone 8861 and 8865 Wireless LAN Deployment Guide
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The Cisco IP Phone 8861 and 8865 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 IP Phone 8861 and 8865 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 IP Phone
8861 and 8865 also meet the access point’s receiver sensitivity (required signal level for the current data rate).
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 IP Phone 8861 and 8865 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 IP Phone
8861 and 8865 also meet the access point’s receiver sensitivity (required signal level for the current data rate).
Dynamic Frequency Selection (DFS)
DFS dynamically instructs a transmitter to switch to another channel whenever radar signal is detected. If the access point
detects radar, the radio on the access point goes on hold for at least 60 seconds while the access point passively scans for
another usable channel.
TPC allows the client and access point to exchange information, so that the client can dynamically adjust the transmit power.
The client uses only enough energy to maintain association to the access point at a given data rate. As a result, the client
contributes less to adjacent cell interference, which allows for more densely deployed, high-performance wireless LANs.
If there are repeated radar events detected by the access point (just or falsely), determine if the radar signals are impacting a
single channel (narrowband) or multiple channels (wideband), then potentially disable use of that channel or channels in the
wireless LAN.
The presence of an access point on a non-DFS channel can help minimize voice interruptions.
In case of radar activity, have at least one access point per area that uses a non-DFS channel (UNII-1). This ensures that a
channel is available when an access point’s radio is in its hold-off period while scanning for a new usable channel.
A UNII-3 channel (5.745 - 5.825 GHz) can optionally be used if available.
Below is a sample 5 GHz wireless LAN deployment.
detects radar, the radio on the access point goes on hold for at least 60 seconds while the access point passively scans for
another usable channel.
TPC allows the client and access point to exchange information, so that the client can dynamically adjust the transmit power.
The client uses only enough energy to maintain association to the access point at a given data rate. As a result, the client
contributes less to adjacent cell interference, which allows for more densely deployed, high-performance wireless LANs.
If there are repeated radar events detected by the access point (just or falsely), determine if the radar signals are impacting a
single channel (narrowband) or multiple channels (wideband), then potentially disable use of that channel or channels in the
wireless LAN.
The presence of an access point on a non-DFS channel can help minimize voice interruptions.
In case of radar activity, have at least one access point per area that uses a non-DFS channel (UNII-1). This ensures that a
channel is available when an access point’s radio is in its hold-off period while scanning for a new usable channel.
A UNII-3 channel (5.745 - 5.825 GHz) can optionally be used if available.
Below is a sample 5 GHz wireless LAN deployment.