AudioCodes Mediant 1000 User Manual page 401

User's Manual
Parameter
Extension Coders Group
sbc-ext-coders-group-name
[IpProfile_SBCExtensionCode
rsGroupName]
Allowed Audio Coders
allowed-audio-coders-group-
name
[IpProfile_SBCAllowedAudioC
odersGroupName]
Allowed Coders Mode
sbc-allowed-coders-mode
[IpProfile_SBCAllowedCoders
Mode]
Version 7.2
packets transparently (RTP-to-RTP), without processing them.

[1] Force = Transcoding is always done on the outgoing leg. The
device interworks the media for the SIP entity (as both legs have
different media capabilities), by implementing DSP transcoding.
This enables the device to receive capabilities that are not
negotiated between the SIP entities. For example, it can enforce
gain control to use voice transcoding even though both legs have
negotiated without the device's intervention (such as extension
coders).
For more information on extension coders and transcoding, see
Coder Transcoding on page 619,
Note:

To implement transcoding, you must configure the number of
required DSP channels for transcoding (using the MediaChannels
parameter). Each transcoding session uses two DSP resources.

When transcoding is required, it is recommended that the device
be installed with the MPM(s) module for handling this
functionality.

The corresponding global parameter is TranscodingMode.
Assigns a Coder Group used for extension coders, added to the SDP
offer in the outgoing leg for the SIP entity associated with the IP
Profile. This is used when transcoding is required between two IP
entities (i.e., the SDP answer from one doesn't include any coder
included in the offer previously sent by the other).
For more information on extension coders and transcoding, see
Coder Transcoding on page 619,
To configure Coder Groups, see Configuring Coder Groups on page
385.
Assigns an Allowed Audio Coders Group, which defines audio
(voice) coders that can be used for the SIP entity associated with the
IP Profile.
To configure Allowed Audio Coders Groups, see Configuring Allowed
Audio Coder Groups on page 389. For a description of the Allowed
Coders feature, see ''Restricting Coders'' on page 618.
Defines the mode of the Allowed Coders feature for the SIP entity
associated with the IP Profile.

[0] Restriction = In the incoming SDP offer, the device uses only
Allowed coders; the rest are removed from the SDP offer (i.e.,
only coders common between those in the received SDP offer
and the Allowed coders are used). If an Extension Coders Group
is also assigned (using the 'Extension Coders Group' parameter,
above), these coders are added to the SDP offer if they also
appear in Allowed coders.

[1] Preference = The device re-arranges the priority (order) of the
coders in the incoming SDP offer according to their order of
appearance in the Allowed Audio Coders Group or Allowed Video
Coders Group. The coders in the original SDP offer are listed
after the Allowed coders.

[2] Restriction and Preference = Performs both Restriction and
401
19. Coders and Profiles
Description
Mediant 1000B Gateway & E-SBC