SIP

SIP Telephony

SIP Codecs

Choosing codecs priority

Note: optimal codecs priority can be another for you and it depends be based on requirements to voice quality, link utilization, and support by hardware.

Following list is constructed based on voice quality requirement with its decreasing while moving to the bottom of the list (codecs on the top providing best voice quality, but consumpts more network traffic):

• G.722
• G.711 (A-law), (known as PCMA)
• G.711 (μ-law), (known as PCMU)
• OPUS
• G.726
• G.721
• iLBC
• G.729
• G.722.1
• G.722.2 (known as AMR-WB)
• GSM-FR (known as GSM)
• G.723

Sources: wikipedia.org, wiki.sipnet.ru, wiki.sipnet.ru, grandstreamnetworks.ru