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Packet Loss Resistance Configurations
To achieve good audio and video quality when there are many participants joining meeting from link, it is
recommended to configure below packet loss resistance related settings on the UCM.
Log in UCM web UI → Call Features → Video Conference, open Conference Settings page to configure
the following options:
Figure 16: Video Conference Settings
- Audio Codec Preference:
Select Opus to add to the selected codec list. Opus has built-in inbandfec support which can
prevent packet loss.
- Packet Loss Retransmission:
• NACK: Retransmit original packet
• NACK+RTX: Retransmit packet with new RTP header. This option provides more accurate
packet loss statistics compared to NACK.