The RTCRtpStreamStats dictionary's ssrc property provides the Synchronization Source (SSRC), an integer which uniquely identifies the source of the RTP packets whose statistics are covered by the RTCStatsReport that includes this RTCRtpStreamStats dictionary.


var ssrc = RTCRtpStreamStats.ssrc;


The Synchronization Source (SSRC) is a 32-bit integer uniquely identifying the source of the RTP packets whose statistics are covered by the RTCStatsReport object of which this RTCRtpStreamStats object is a component.

The manner in which these values are generated is not mandated by the specification, although it does make recommendations. You should not make any assumptions based on the value of ssrc other than that any two objects with the same ssrc value refer to the same source. See RFC 3550, section 8 for additional information about ssrc.

Note: The specification includes an example that generates values for ssrc using MD5. While not part of the standard, exactly, it is a good mechanism that may be used by some browsers; others may use other methods, such as random number generators. Do not rely upon these values meaning anything other than "these objects are associated with the same source."


Specification Status Comment
Identifiers for WebRTC's Statistics API
The definition of 'RTCRtpStreamStats.ssrc' in that specification.
Candidate Recommendation Initial definition.

Browser compatibility

Update compatibility data on GitHub
ChromeEdgeFirefoxInternet ExplorerOperaSafariAndroid webviewChrome for AndroidFirefox for AndroidOpera for AndroidSafari on iOSSamsung Internet
ssrcChrome No support NoEdge No support NoFirefox Full support 27IE No support NoOpera No support NoSafari ? WebView Android No support NoChrome Android No support NoFirefox Android Full support 27Opera Android No support NoSafari iOS ? Samsung Internet Android No support No


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Full support
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Compatibility unknown