VoIP profile configuration task list
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SmartWare Software Configuration Guide
47 • VoIP profile configuration
The operating modes for the dejitter buffer are illustrated in
figure 4
:
•
Adaptive—The adaptive buffer automatically adapts to variations in the network’s delay characteristics and
in general yields the best results for voice conversations.
•
Static—The static buffer is useful for voice conversations if you have specific information about your net-
work’s delay characteristics (such as jitter period, etc.), so it should only be used by experienced users.
•
Static-data—The static-data mode if you want to create a profile for fax or modem transmission without
using the T.38 or fax bypass features described later in this chapter
Figure 4. Adaptive versus static dejitter buffer
Procedure:
Configure the dejitter buffer.
In the adaptive dejitter buffer there are parameters that can be
configured (such as shrink-speed, grow-step, etc.) that should not
be changed unless it is necessary to do so. An incorrect configura-
tion can lead to interoperability problems and loss of service.
Therefore, it is strongly recommended that only expe-
rienced users change these parameters.
IMPORTANT
Adaptive
Fixed
max delay => max fill level
Adaptive algorithm resizes
buffersize up to max delay,
depending on network traffic !
voice packets
max delay => buffersize
Fixed algorithm sets buffersize to max delay.
Generally mean delay of voice packets is
max delay / 2
voice packets
mean delay = max delay / 2
