Cisco Cisco IP Phone 8841 Guía De Diseño
Cisco IP Phone 8861 and 8865 Wireless LAN Deployment Guide
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Quality of Service (QoS)
Quality of Service enables queuing to ensure high priority for voice traffic.
To enable proper queuing for voice and call control traffic use the following guidelines.
To enable proper queuing for voice and call control traffic use the following guidelines.
• Ensure that WMM is enabled on the access point.
• Create a QoS policy on the access point giving priority to voice and call control traffic.
Traffic Type
DSCP
802.1p
WMM UP
Port Range
Voice
EF (46)
5
6
UDP 16384 - 32767
Call Control
CS3 (24)
3
4
TCP 5060 - 5061
• Be sure that voice and call control packets have the proper QoS markings and other protocols are not using the same
QoS markings.
• Enable Differentiated Services Code Point (DSCP) preservation on the Cisco IOS switch.
For more information about TCP and UDP ports used by the Cisco IP Phone 8861 and 8865 and the Cisco Unified
Communications Manager, refer to the Cisco Unified Communications Manager TCP and UDP Port Usage document at this
URL:
http://www.cisco.com/c/en/us/td/docs/voice_ip_comm/cucm/port/10_0_1/CUCM_BK_T537717B_00_tcp-port-usage-guide-
100.html
100.html
Call Admission Control (CAC)
Call Admission Control can be enabled on the access point.
• Enable Call Admission Control (CAC) / Wi-Fi MultiMedia Traffic Specifications (TSPEC) for Voice
• Set the desired maximum RF bandwidth that is allocated for voice traffic (default = 75%)
• Set the bandwidth that is reserved for roaming voice clients (default = 6%)
The Cisco IP Phone 8861 and 8865 will specify 12 Mbps for the PHY rate to be used for TSPEC.
Pre-Call Admission Control
If Call Admission Control is enabled on the access point, the Cisco IP Phone 8861 and 8865 will send an Add Traffic Stream
(ADDTS) to the access point to request bandwidth in order to place or receive a call.
If the AP sends an ADDTS successful message then the Cisco IP Phone 8861 or 8865 establishes the call.
If the access point rejects the call and the Cisco IP Phone 8861 or 8865 has no other access point to roam to, then the phone will
display Network Busy.
If the admission is refused for an inbound call there is no messaging from the Cisco IP Phone 8861 or 8865 to inform the
remote endpoint that there is insufficient bandwidth to establish the call, so the call can continue to ring out within the system
until the remote user terminates the call.
(ADDTS) to the access point to request bandwidth in order to place or receive a call.
If the AP sends an ADDTS successful message then the Cisco IP Phone 8861 or 8865 establishes the call.
If the access point rejects the call and the Cisco IP Phone 8861 or 8865 has no other access point to roam to, then the phone will
display Network Busy.
If the admission is refused for an inbound call there is no messaging from the Cisco IP Phone 8861 or 8865 to inform the
remote endpoint that there is insufficient bandwidth to establish the call, so the call can continue to ring out within the system
until the remote user terminates the call.