vncs Vp New Voice Encoding Choice Table

1.3.6.1.4.1.562.2.4.1.44.3.382

This attribute specifies preferences regarding the encoding of voice traffic. During the setup of an audio call, the local and remote ends negotiate a common encoding to use. The local end's ordered list of preferred encodings is given by all voiceEncodingChoice elements that are not set to none. Prior to negotiation, the local end removes encodings from its list that it cannot use for a particular call. For example, the card for a particular call may not support certain encodings. After this local check, the local end sends its voice encoding preferences to the remote end. The remote end chooses the most preferred encoding that it can support from the list and this encoding is the one used during voice traffic. If the remote end cannot support any encodings on the local end's list, a call does not proceed and an alarm is issued. The current encoding and encoding rate are available in Vsr Svs currentEncoding and Vsr Svs currentRate. The encoding choice g711Only specifies that pulse code modulation (PCM) defined by ITU-T G.711 should be performed to encode voice traffic for calls using this profile. In this case, all voice traffic is carried uncompressed at 64 kbit/s. The encoding choice g711G726 specifies that either pulse code modulation (PCM) defined by ITU-T G.711 or adaptive differential pulse code modulation (ADPCM) defined by ITU-T G.726 should be performed to encode voice traffic for calls using this profile. The actual encoding performed depends on congestion in the network and the settings of the g711G726 row of the voiceRates attribute. The encoding choice of g728Only specifies that the Low Delay Coded Excited Linear Predictive Coder (LD-CELP) algorithm defined by ITU-T G.728 should be performed to encode voice traffic for calls using this profile. In this case, all voice traffic is carried at 16 kbit/s. The encoding choice of g729Only specifies that the Conjugated Structure Algebraic Code Excited Linear Predictive Coder (CS-ACELP) algorithm defined by ITU-T G.729 should be performed to encode voice traffic for calls using this profile. In this case, all voice traffic is carried at 8 kbit/s. The encoding choice of none specifies the end of the encoding choice list. No other encoding choice can appear after none, and none cannot appear as the first choice. The only encoding choice that can appear more than once in voiceEncodingChoice is none. G.728 and G.729 encoding cannot be performed on a 1pDS1V, 1pE1V or J2MV card. The negotiated voice encoding is available in Vsr Svs Framer negotiatedEncoding.