Page 369 - Asterisk™: The Future of Telephony

The jitter buffer is, in a sense, a staging area where the packets can be reordered
and delivered in a regulated stream. Without a jitter buffer, the user may perceive
anomalies in the stream, experienced as static, strange sound effects, garbled
words, or, in severe cases, missed words or syllables.
The jitter buffer affects only data received from the far end. Any data you transmit
will not be affected by your jitter buffer, as the far end will be responsible for the
de-jittering of its incoming connections.
The jitter buffer is enabled with the use of jitterbuffer=yes:
jitterbuffer=yes|no
language (channel)
This sets the language flag to whatever you define. The global default language is
English. The language that is set is sent by the channel as an information element.
It is also used by applications such as SayNumber() that have different files for dif-
ferent languages. Keep in mind that languages other than English are not explicitly
installed on the system, and it is up to you to configure the system to ensure that
the language you specify is handled properly:
language=en
mailboxdetail (global)
If mailboxdetail is set to yes, the new/old message count is sent to the user, instead
of a simple statement of whether new and old messages exist. mailboxdetail can
also be set on a per-peer basis:

mailboxdetail=yes
maxjitterbuffer (channel)
This parameter is used to set the maximum size of the jitter buffer, in milliseconds.
Be sure not to set maxjitterbuffer too high, or you will needlessly increase your
latency:

maxjitterbuffer=500
maxjitterinterps (channel)
The maximum number of interpolation frames the jitter buffer should return in a
row. Since some clients do not send CNG/DTX frames to indicate silence, the jitter
buffer will assume silence has begun after returning this many interpolations. This
prevents interpolating throughout a long silence:
maxjitterinterps=10
maxregexpire and minregexpire (channel)
Specifies the maximum and minimum time intervals for registration expiration, in
seconds:
maxregexpire=180
minregexpire=60

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