Voice Qos - Yealink SIP-T2xP Administrator's Manual

Administrator's Guide for SIP-T2xP and SIP-T19P IP Phones
VoIP is extremely bandwidth- and delay-sensitive. QoS is a major issue in VoIP
implementations, regarding how to guarantee that packet traffic not be delayed or
dropped due to interference from other lower priority traffic. VoIP can guarantee
high-quality QoS only if the voice and the SIP packets are given priority over other kinds
of network traffic. IP phones support the DiffServ model of QoS.

Voice QoS

In order to make VoIP transmissions intelligible to receivers, voice packets should not be
dropped, excessively delayed, or made to suffer varying delay. DiffServ model can
guarantee high-quality voice transmission when the voice packets are configured to a
higher DSCP value.
SIP QoS
SIP protocol is used for creating, modifying and terminating two-party or multi-party
sessions. To ensure good voice quality, SIP packets emanated from IP phones should be
configured with a high transmission priority.
DSCPs for voice and SIP packets can be specified respectively.
Procedure
QoS can be configured using the configuration files or locally.
Configuration File
Local
To configure DSCPs for voice packets and SIP packets via web user interface:
1. Click on Network->Advanced.
2. Enter the desired value in the Voice QoS (0~63) field.
196
<y0000000000xx>.cfg
Web User Interface
Configure the DSCPs for voice
packets and SIP packets.
For more information, refer to
QoS on page 379.
Configure the DSCPs for voice
packets and SIP packets.
Navigate to:
http://<phoneIPAddress>/servl
et?p=network-adv&q=load