RTCOutboundRtpStreamStats: retransmittedBytesSent property

Baseline Widely available

This feature is well established and works across many devices and browser versions. It’s been available across browsers since January 2020.

The retransmittedBytesSent property of the RTCOutboundRtpStreamStats dictionary represents the total number of payload bytes retransmitted for the source associated with this stream.

RTX (Retransmission) is one of several mechanisms that WebRTC uses for retransmitting lost payload bytes, and broadly refers to support for the special packets defined in RFC 4588. RTX has to be negotiated between the sender and receiver during initial handshake. If RTX has not been negotiated the retransmitted bytes will be sent over the same SSRC; otherwise the bytes are sent on a separate SSRC but are still accounted for in this property.

The retransmitted bytes sent are included in the count reported by bytesSent.

Value

A positive integer indicating the number of retransmitted payload bytes for the source.

Specifications

Specification
Identifiers for WebRTC's Statistics API
# dom-rtcoutboundrtpstreamstats-retransmittedbytessent

Browser compatibility

BCD tables only load in the browser