RTX stands for retransmission.

In the context of WebRTC, this refers to IETF RC 4588 that defines a special RTP payload that is used to retransmit packets that were previously sent.

While retransmission is usually useless in RTC, there are times where it can make sense – especially if a previous frame needs to be used for the decoding of fresh frames.

About WebRTC Glossary

The WebRTC Glossary is an ongoing project where users can learn more about WebRTC related terms. It is maintained by Tsahi Levent-Levi of BlogGeek.me.

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