Coders And Profiles; Configuring Default Coders - AudioCodes Mediant 800B User Manual

User's Manual
19

Coders and Profiles

This section describes configuration of the coders and SIP profiles parameters.
19.1

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
390) 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.
•
Opus coder:
√
√
•
For information on V.152 and implementation of T.38 and VBD coders, see
''Supporting V.152 Implementation'' on page 193.
The following procedure describes how to configure the Coders table through the Web
interface. You can also configure it through ini file (CodersGroup) or CLI (configure voip >
coders-and-profiles coders-group).
Version 7.0
For SBC calls: If one leg uses a narrowband coder (e.g., G.711) and the other
leg uses the Opus coder, the device maintains the narrowband coder flavor by
using the narrowband Opus coder. Alternatively, if one leg uses a wideband
coder (e.g., G.722) and the other leg uses the Opus coder, the device
maintains the wideband coder flavor by using the wideband Opus coder.
Gateway calls always use the narrowband Opus coder.
387 Mediant 800B Gateway and E- SBC
19. Coders and Profiles