Cisco Cisco IP Phone 8841 Designanleitung
Cisco IP Phone 8861 and 8865 Wireless LAN Deployment Guide
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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.
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.
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.
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 IP
Phone 8861 and 8865 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 IP Phone 8861 and 8865 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.
Due to the potential of elevated multipath in rugged environments, the transmit power of the access point and Cisco IP
Phone 8861 and 8865 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 IP Phone 8861 and 8865 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
It is recommended to utilize 802.11r / Fast Transition (FT)
It is recommended to utilize 802.11r / Fast Transition (FT)
for fast roaming. Enabling 802.11r (FT) also reduces the
number of frames in the handshake when roaming to only two frames. Reducing the number of frames during a roam,
increases the chances of roam success.
When using 802.1x authentication, it is important to use the recommended EAPOL key settings.
increases the chances of roam success.
When using 802.1x authentication, it is important to use the recommended EAPOL key settings.
Quality of Service (QoS)
Need to ensure that DSCP values are preserved throughout the wired network, so that the WMM UP tag for voice,
video, and call control frames can be set correctly.
Need to ensure that DSCP values are preserved throughout the wired network, so that the WMM UP tag for voice,
video, and call control frames can be set correctly.
Beamforming
If using Cisco 802.11n capable access points, then Beamforming (ClientLink) should be enabled, which can help with
client reception.
If using Cisco 802.11n capable access points, then Beamforming (ClientLink) should be enabled, which can help with
client reception.
Multipath
Multipath occurs when RF signals take multiple paths from a source to a destination.
A part of the signal goes to the destination while another part bounces off an obstruction, then goes on to the destination. As a
result, part of the signal encounters delay and travels a longer path to the destination, which creates signal energy loss.
A part of the signal goes to the destination while another part bounces off an obstruction, then goes on to the destination. As a
result, part of the signal encounters delay and travels a longer path to the destination, which creates signal energy loss.
When the different waveforms combine, they cause distortion and affect the decoding capability of the receiver, as the signal
quality is poor.
Multipath can exist in environments where there are reflective surfaces (e.g. metal, glass, etc.). Avoid mounting access points
on these surfaces.
quality is poor.
Multipath can exist in environments where there are reflective surfaces (e.g. metal, glass, etc.). Avoid mounting access points
on these surfaces.
Below is a list of multipath effects:
Data Corruption