Polycom DOC2237A - Manual (Page 125)

MGC Hardware and Installation Manual
4-53
Audio Module (Standard)
The Audio Module performs audio compression, decompression, and
bridging. The Audio Module also performs transcoding between various
audio algorithms.
The Audio Module supports the following algorithms:
• ITU-T G.711 48, 56, and 64 Kbps
• ITU-T G.722 48, 56, and 64 Kbps
• ITU-T G.728 16 Kbps
Audio Module Port Capacity
The Audio module contains 13 units. The first unit is the Audio Bridge, which
is the controller used for audio mixing of the participants and to identify the
conference speaker. The remaining 12 units (2 to 13) are used to connect the
audio channels of the participants, one unit per codec. Each codec performs
audio coding and decoding. Each codec works with one endpoint and is
capable of using any of the following audio algorithms: G.711, G.722, G.728,
G.722.1 and Siren7.
The module may contain two additional units (14 and 15). These units are
used for Greet and Guide conferences and have to be configured in the
“system cfg.” In such a case, port number 14 is used for music, and port
number 15 is used for the audio message, used in Greet and Guide
conferences.
The Audio Bridge can run four conferences simultaneously, totaling up to 16
participants (4/16). To increase the maximum number of participants to 30
participants set the Audio Bridge to 1/30. If the Audio Bridge is set to 1/30 it
can run only one conference at a time if the conference includes up to 16
participants and not all the resources are used. The audio card can support up
to six gateway sessions with a maximum of 12 participants. To enable the
gateway sessions set the Audio Bridge to 6/12. When set to 6/12, the audio
cards can run only six conferences with two participants (gateway sessions).
The bridge can use units from the same audio card or from different cards.
The Audio cards are set to 4x16 by default, but you can manually change the
configuration to suit the type of conferences that are required in your site.