Coders And Profiles; Configuring Default Coders - AudioCodes Mediant 3000 User Manual

User's Manual
20

Coders and Profiles

This section describes configuration of the coders and SIP profiles parameters.
20.1

Configuring Default Coders

The Coders table lets you configure up to 11 voice coders for the device. This is the default
Coder Group, which is used by the device for all calls, unless a different Coder Group,
configured in the Coder Group Settings table (see ''Configuring Coder Groups'' on page
385) is assigned to specific calls, using Tel or IP Profiles.
Each coder can be configured with packetization time (ptime), bit rate, payload type, and
silence suppression. The first coder configured in the table has the highest priority and is
used by the device whenever possible. If the remote side cannot use the first coder, the
device attempts to use the next coder in the table, and so on.
Notes:
•
Some coders are license-dependent and are available only if purchased from
AudioCodes and included in the Software License Key installed on your device.
For more information, contact your AudioCodes sales representative.
•
Only the packetization time of the first coder in the coder list is declared in
INVITE/200 OK SDP, even if multiple coders are defined. The device always uses
the packetization time requested by the remote side for sending RTP packets. If
not specified, the packetization time is assigned the default value.
•
The value of several fields is hard-coded according to common standards (e.g.,
payload type of G.711 U-law is always 0). Other values can be set dynamically. If
no value is specified for a dynamic field, a default value is assigned. If a value is
specified for a hard-coded field, the value is ignored.
•
The G.722 coder provides Packet Loss Concealment (PLC) capabilities, ensuring
higher voice quality.
•
For information on V.152 and implementation of T.38 and VBD coders, see
''Supporting V.152 Implementation'' on page 210.
The following procedure describes how to configure the Coders table through the Web
interface. You can also configure it through ini file (CodersGroup).
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20. Coders and Profiles
Mediant 3000