P31003C1020M1000276A9, 01/2018
OpenScape Cordless IP V2, Administrator Documentation
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Telephony settings
Audio quality
Quality of Service (QoS)
The voice quality depends on the priority of the voice data in the IP network. Prioritising the VoIP data packets is
done using the QoS protocol DiffServ (Differentiated Services). DiffServ defines a number of classes for the quality
of service and, within these classes, various priority levels for which specific prioritisation procedures are defined.
You can specify different QoS values for SIP and RTP packets. SIP packets contain the signalling data, while RTP
(Real-time Transport Protocol) is used for the voice transfer.
Enter your chosen QoS values in the
SIP ToS / DiffServ
and
RTP ToS / DiffServ
fields. Value range: 0 - 63.
Common values for VoIP (default setting):
9.2 Audio quality
The phone system allows the user to make calls with excellent voice quality using the wideband codec G.722. One
base station enables a maximum of five wideband calls.
Settings
Telephony
Audio
The page allows you to enable/disable the use of the wideband codec G.722 for the telephone system.
Mark/unmark the check box to enable/disable wideband calls
Click on
Set
to save the settings of this page.
SIP
34
High service class for fast switching of the data flow (Expedited Flow)
RTP
46
Highest service class for fast forwarding of data packets (Expedited Forwarding)
Do not change these values without consulting your network operator first. A higher value does not
necessarily mean a higher priority. The value determines the service class, not the priority. The
prioritisation procedure used in each case meets the requirements of this class and is not necessarily
suitable for transferring voice data.
To allow users to make wideband calls, the codec G.722 must have been activated for the provider
profile that is used for the connection ( p. 45).
