Configuring Allowed Audio Coder Groups - AudioCodes Mediant 800B User Manual

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SILK coder (Skype's default audio codec):
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Opus coder:
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3. Click Apply.
20.2

Configuring Allowed Audio Coder Groups

The Allowed Audio Coders Groups table lets you configure up to 10 Allowed Audio Coders
Groups for SBC calls. For each Allowed Audio Coders Group, you can configure up to 10
audio coders. The coders can include pre-defined coders and user-defined (string) coders
for non-standard or unknown coders.
Allowed Audio Coders Groups restrict coders for SIP entities. Only coders listed in the
Allowed Audio Coders Group (i.e., allowed coders) that is associated with the SIP entity
can be used. If the coders in the SDP offer ('a=rtpmap' field) of the incoming SIP message
are not listed in the Allowed Audio Coders Group, the device rejects the calls, unless
transcoding is configured, whereby "extension" coders are added to the SDP, as described
in Coder Transcoding on page 673. If the SDP offer contains some coders that are listed in
the Allowed Audio Coders Group, the device manipulates the SDP offer by removing the
coders that are not listed in the Allowed Audio Coders Group, before routing the SIP
message to its destination. Thus, only coders that are common between the coders in the
SDP offer and the coders in the Allowed Audio Coders Group are used. For more
information on coder restriction, see 'Restricting Audio Coders' on page 672.
For example, assume the following:
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The SDP offer in the incoming SIP message contains the G.729, G.711, and G.723
coders.
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The allowed coders configured for the SIP entity include G.711 and G.729.
User's Manual
'AMR Payload Format' (AmrOctetAlignedEnable): Defines the AMR payload
format type:
'Silk Tx Inband FEC': Enables forward error correction (FEC) for the SILK
coder.
'Silk Max Average Bit Rate': Defines the maximum average bit rate for the
SILK coder.
Figure 20-2: Configuring SILK Coder Attributes
'Opus Max Average Bitrate' (OpusMaxAverageBitRate): Defines the
maximum average bit rate (in bps) for the Opus coder.
Figure 20-3: Configuring Opus Coder Attributes
Mediant 800B Gateway & E-SBC
432 Document #: LTRT-10632