1. Web
  2. Web APIs
  3. RTCOutboundRtpStreamStats
  4. nackCount

RTCOutboundRtpStreamStats: nackCount property

Baseline Widely available

This feature is well established and works across many devices and browser versions. It’s been available across browsers since March 2022.

The nackCount property of the RTCOutboundRtpStreamStats dictionary is a numeric value indicating the number of times the RTCRtpSender described by this object received a NACK packet from the remote receiver.

A NACK (Negative ACKnowledgement, also called "Generic NACK") packet is used by the RTCRtpReceiver to inform the sender that one or more RTP packets it sent were lost in transport.

Value

An integer value indicating how many times the sender received a NACK packet from the receiver, indicating the loss of one or more packets.

Specifications

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

Browser compatibility

Chrome
Edge
Firefox
Opera
Safari
Chrome Android
Firefox for Android
Opera Android
Safari on iOS
Samsung Internet
WebView Android
WebView on iOS
nackCount in 'outbound-rtp' stats
Chrome – Full support
Chrome 93 (Release date: 2021-08-31)
footnote Full support
Edge – Full support
Edge 93 (Release date: 2021-09-02)
footnote Full support
Firefox – Full support
Firefox 55 (Release date: 2017-08-08)
footnote Full support
Opera – Full support
Opera 79 (Release date: 2021-09-14)
footnote Full support
Safari – Full support
Safari 15.4 (Release date: 2022-03-14)
footnote Full support
Chrome Android – Full support
Chrome Android 93 (Release date: 2021-08-31)
footnote Full support
Firefox for Android – Full support
Firefox for Android 55 (Release date: 2017-08-08)
footnote Full support
Opera Android – Full support
Opera Android 66 (Release date: 2021-12-15)
footnote Full support
Safari on iOS – Full support
Safari on iOS 15.4 (Release date: 2022-03-14)
footnote Full support
Samsung Internet – Full support
Samsung Internet 17 (Release date: 2022-05-04)
footnote Full support
WebView Android – Full support
WebView Android 93 (Release date: 2021-08-31)
footnote Full support
WebView on iOS – Full support
WebView on iOS 15.4 (Release date: 2022-03-14)
footnote Full support

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Full support

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