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Collaboration, Voice & AV · Intermediate

Voice Class Codec

An IOS list of preferred codecs that a dial peer offers or accepts, in order of preference.

Definition

voice class codec lists codecs such as G.711ulaw and G.729r8 with preference numbers, and dial peers reference it with voice-class codec. It controls SDP offers and allows codec filtering on CUBE. For transcoding needs, CUBE can use local DSP transcoders or codec transparent passing.

Example

voice class codec 1 / codec preference 1 g711ulaw / codec preference 2 g729r8 is applied to the ITSP dial peer.

Exam tip

A codec mismatch between dial peers and the carrier commonly returns SIP 488.

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