5.8.2 Modification of Available Codecs List
23.1533GPPOut of band transcoder controlRelease 17Stage 2TS
The modification of the Available Codecs List (BICC) shall support the following changes:
1) reduction of the ACS of any Single Codec information element in the Available Codecs List (BICC) for which OM is set to "Optimization of the ACS supported";
2) reduction of the SCS of any Single Codec information element in the Available Codecs List (BICC) for which OM is set to "Optimization of the ACS supported";
3) reduction of the MACS of any Single Codec information element in the Available Codecs List (BICC) for which OM is set to "Optimization of the ACS supported";
4) change of the OM of any Single Codec information element in the Available Codecs List (BICC) from "Optimization of the ACS supported" to "not supported"; and
5) deletion of one or more Single Codec information elements from the Available Codecs List (BICC).
This shall not include the removal of the Selected Codec (BICC) or of modes from the ACS of the Selected Codec (BICC), as this would require a Modification of Selected Codec as described in 5.8.1.
The procedures described in Q.1902.4, clauses 10.4.1 to 10.4.3 [6] shall apply.
For the coding of the new Available Codecs List (BICC), the same rules apply as specified in clause 5.6.4.
No modification of the user plane and signalling towards the MGWs and radio access network is required.
In Figure 5.8.2/1 the basic "modification of available codec list" procedure is shown. This Figure is an example; the codec modification procedure may be initiated by any node within the call.
Figure 5.8.2/1: Modification of Available Codec List