Codec

A Codec also known as Coding Decoding is a compression mechanism which reduces the bandwidth required for the call.

Bandwidth required for a normal PSTN call ==64kbps




MoS Mean Opinion score is a Value which tells about the quality of a call.

G711 is uncompressed codec. It uses 64 kbps and has the highest MoS.
G729 is widely used compressed codec and has a MoS of 3.9.


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