Nortel 1110 Installation And Operation Manual page 258

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553-3001-368 Standard 26.00
Nortel Mobile Voice Client 2050
Table 26
Advanced Audio screen (Part 2 of 2)
Selection
Highwater Mark
Early Packet and Late Packet
Resync
Echo cancellation
MVC 2050 can use the Voice Gateway Media Card for echo cancellation.
Jitter Buffer
Global IP Sound NetEQ, bundled with MVC 2050 software, provides loss
concealment and compensation for up to 30% packet loss.
NetEQ is an advanced jitter buffer and packet loss concealment unit that
delivers improvements in sound quality, while minimizing latency, for IP
telephone systems. It is a one-sided, embedded solution that enables
high-quality voice over networks. NetEQ reduces jitter buffer delay 30-80 ms
and automatically provides a solution to clock drift present in VoIP hardware.
NetEQ is codec independent.
The jitter buffer is used to minimize a change in rate for arriving voice frames.
The jitter buffer sends voice frames to the PDA sound system at a fixed rate.
August 2007
Description
Highwater Mark indicates the
maximum number of voice frames
the application should have in its
jitter buffer before it starts
discarding packets. This value
should be at least 2.5 times the
value of jitter. If a smaller value is
assigned, MVC 2050 regards it as
an error and corrects it.
Early Packet Resync and Late
Packet Resync indicate the points
at which MVC 2050 discards and
restarts the jitter buffer contents.
This value should be at least five
the
times Highwater Mark
.