AudioCodes Mediant 500 MSBR, Руководство пользователя

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User's Manual 400 Document #: LTRT-10375
Mediant 500 MSBR
♦
'Silk Max Average Bit Rate': Defines the maximum average bit rate for the
SILK coder.
Figure 23-2: Configuring SILK Coder Attributes
3. Click Apply .
23.2 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. 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 640.
For example, assume the following:

The SDP offer in the incoming SIP message contains the G.729, G.711, and G.723
coders.

The allowed coders configured for the SIP entity include G.711 and G.729.
The device removes the G.723 coder from the SDP offer, re-orders the coder list so that
G.711 is listed first, and sends the SIP message containing only the G.711 and G.729
coders in the SDP.
To apply an Allowed Audio Coders Group for restricting coders to a SIP entity:
1. Configure an Allowed Audio Coders Group in the Allowed Audio Coders Groups table
(see description below).
2. In the IP Profile associated with the SIP entity (see Configuring IP Profiles on page
404):
•
Assign the Allowed Audio Coders Group (using the
IpProfile_SBCAllowedAudioCodersGroupName parameter).
•
Enable the use of Allowed Audio Coders Groups (by configuring the
IpProfile_SBCAllowedCodersMode parameter to
Restriction or Restriction and
Preference ).
The device also re-orders (prioritizes) the coder list in the SDP according to the order of
appearance of the coders listed in the Allowed Audio Coders Group. The first listed coder
has the highest priority and the last coder has the lowest priority. For more information, see
Prioritizing Coder List in SDP Offer on page 641.