The optional property usernameFragment in the RTCIceCandidateInit dictionary specifies the value of the RTCIceCandidate object's usernameFragment property.


A DOMString containing the username fragment (usually referred to in shorthand as "ufrag" or "ice-ufrag") that, along with the ICE password ("ice-pwd"), uniquely identifies a single ongoing ICE interaction. The string may be up to 256 characters long, and has no default value.

At least 24 bits of the text in the ufrag are required to be randomly selected by the ICE layer at the beginning of the ICE session. The specifics for which bits are random and what the remainder of the ufrag text are are left up to the browser implementation to decide. For example, a browser might choose to always use a 24-character password in which bit 4 of each character is randomly selected between 0 and 1. Another example: it might take a user-defined string and append three 8-bit random bytes to the end. Or perhaps every character is entirely random.




Specification Status Comment
WebRTC 1.0: Real-time Communication Between Browsers
The definition of 'RTCIceCandidateInit.usernameFragment' in that specification.
Candidate Recommendation Initial specification.

Browser compatibility

FeatureChromeEdgeFirefoxInternet ExplorerOperaSafari
Basic support Yes Yes22 ? Yes ?
FeatureAndroid webviewChrome for AndroidEdge mobileFirefox for AndroidOpera AndroidiOS SafariSamsung Internet
Basic support Yes Yes Yes Yes Yes ? Yes

See also

Document Tags and Contributors

Contributors to this page: Sheppy
Last updated by: Sheppy,