Web/API/RTCIceCandidate/type

The RTCIceCandidate interface's read-only type specifies the type of candidate the object represents.

The type field's value is set when the RTCIceCandidate() constructor is used. You can't specify the value of type in the options object, but the address is automatically extracted from the candidate a-line, if it's formatted properly, being taken from its cand-type field.

Syntax

var type = RTCIceCandidate.type;

Value

A DOMString whose value is one of those defined by the RTCIceCandidateType enumerated type.

These candidate types are listed in order of priority; the higher in the list they are, the more efficient they are.

host: The candidate is a host candidate, whose IP address as specified in the RTCIceCandidate.ip property is in fact the true address of the remote peer.
srflx: The candidate is a server reflexive candidate; the ip indicates an intermediary address assigned by the STUN server to represent the candidate's peer anonymously.
prflx: The candidate is a peer reflexive candidate; the ip is an intermediary address assigned by the STUN server to represent the candidate's peer anonymously.
relay: The candidate is a relay candidate, obtained from a TURN server. The relay candidate's IP address is an address the TURN server uses to forward the media between the two peers.

If type is null, that information was missing from the candidate's a-line, which will cause RTCPeerConnection.addIceCandidate() to throw an OperationError exception.

Example

In this example, the candidate's type is used to present a modified user interface for host candidates (those where the ip refers directly to the remote peer, rather than an intermediary).

if (candidate.type == "host") {
  showHostControls();
} else {
  hideHostControls();
}

Specifications

Specification	Status	Comment
WebRTC 1.0: Real-time Communication Between BrowsersThe definition of 'RTCIceCandidate.type' in that specification.	Candidate Recommendation	Initial definition.

Browser compatibility

Update compatibility data on GitHub

	Desktop						Mobile
	Chrome	Edge	Firefox	Internet Explorer	Opera	Safari	Android webview	Chrome for Android	Firefox for Android	Opera for Android	Safari on iOS	Samsung Internet
`type`	Chrome Full support 74	Edge Full support ≤18	Firefox No support No	IE No support No	Opera No support No	Safari ?	WebView Android Full support 74	Chrome Android Full support 74	Firefox Android No support No	Opera Android No support No	Safari iOS ?	Samsung Internet Android Full support 11.0

Legend

Full support: Full support
No support: No support
Compatibility unknown: Compatibility unknown