Cisco Cisco IP Phone 8841 Designanleitung
Cisco IP Phone 8861 and 8865 Wireless LAN Deployment Guide
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Wireless LAN is automatically disabled temporarily when Ethernet is connected to the Cisco IP Phone 8861 or 8865, but will
be automatically re-enabled once Ethernet is disconnected if Wireless LAN was enabled previously.
The Cisco IP Phone 8861 and 8865 primarily use active mode (no Wi-Fi power save) when in idle or on call.
be automatically re-enabled once Ethernet is disconnected if Wireless LAN was enabled previously.
The Cisco IP Phone 8861 and 8865 primarily use active mode (no Wi-Fi power save) when in idle or on call.
Null Power Save (PS-NULL) frames are utilized for off-channel scanning.
Delivery Traffic Indicator Message (DTIM)
It is recommended to set the DTIM period to 2 with a beacon period of 100 ms.
Since the Cisco IP Phone 8861 and 8865 use active mode, the DTIM period will not be used to schedule wake up periods to
check for broadcast and multicast packets as well as any unicast packets.
Broadcast and multicast traffic will be queued until the DTIM period when there are power save enabled clients associated to
the access point, so DTIM will determine how quickly these packets can be delivered to the client. If using multicast
applications, a shorter DTIM period can be used.
When multiple multicast streams exist on the wireless LAN frequently, then it is recommended to set the DTIM period to 1.
Since the Cisco IP Phone 8861 and 8865 use active mode, the DTIM period will not be used to schedule wake up periods to
check for broadcast and multicast packets as well as any unicast packets.
Broadcast and multicast traffic will be queued until the DTIM period when there are power save enabled clients associated to
the access point, so DTIM will determine how quickly these packets can be delivered to the client. If using multicast
applications, a shorter DTIM period can be used.
When multiple multicast streams exist on the wireless LAN frequently, then it is recommended to set the DTIM period to 1.
Dynamic Transmit Power Control (DTPC)
To ensure packets are exchanged successfully between the Cisco IP Phone 8861 or 8865 and the access point, Dynamic
Transmit Power Control (DTPC) should be enabled.
DTPC prevents one-way audio when RF traffic is heard in one direction only.
If the access point does not support DTPC, then the Cisco IP Phone 8861 and 8865 will use the highest available transmit power
depending on the current channel and data rate.
The access point’s radio transmit power should not have a transmit power greater than what the Cisco IP Phone 8861 and 8865
can support.
Transmit Power Control (DTPC) should be enabled.
DTPC prevents one-way audio when RF traffic is heard in one direction only.
If the access point does not support DTPC, then the Cisco IP Phone 8861 and 8865 will use the highest available transmit power
depending on the current channel and data rate.
The access point’s radio transmit power should not have a transmit power greater than what the Cisco IP Phone 8861 and 8865
can support.
Call Capacity
Design the network to accommodate the desired call capacity.
The Cisco Access Point can support up to 27 bi-directional voice streams for both 802.11a/n/ac and 802.11g/n at a data rate of
24 Mbps or higher. To achieve this capacity, there must be minimal wireless LAN background traffic and initial radio frequency
(RF) utilization.
The number of calls may vary depending on the data rate, initial channel utilization, and the environment.
The Cisco Access Point can support up to 27 bi-directional voice streams for both 802.11a/n/ac and 802.11g/n at a data rate of
24 Mbps or higher. To achieve this capacity, there must be minimal wireless LAN background traffic and initial radio frequency
(RF) utilization.
The number of calls may vary depending on the data rate, initial channel utilization, and the environment.
Audio Only Calls
Below lists the maximum number of audio only calls (single bi-directional voice stream) supported per access point / channel.
Max # of
Streams
Audio Codec
Audio
Bit Rate
802.11 Mode
Data Rate
13
G.722 / G.711 64 Kbps
802.11a/n or 802.11g/n +
Bluetooth Disabled
Bluetooth Disabled
6 Mbps
20
G.722 / G.711 64 Kbps
802.11a/n or 802.11g/n +
Bluetooth Disabled
Bluetooth Disabled
12 Mbps
27
G.722 / G.711 64 Kbps
802.11a/n/ac or 802.11g/n
+ Bluetooth Disabled
+ Bluetooth Disabled
24 Mbps or higher