RTCIceCandidate: tcpType property

The RTCIceCandidate interface's read-only tcpType property is included on TCP candidates to provide additional details about the candidate type.

The tcpType field's value is set from the candidateInfo options object passed to the RTCIceCandidate() constructor. You can't specify the value of tcpType directly in the options object, but its value is automatically extracted from the object's candidate a-line, if it's formatted properly.

Value

If the protocol is "tcp", tcpType has one of the following values:

"active"

The transport will try to open an outbound connection but won't receive incoming connection requests.

"passive"

The transport will receive incoming connection requests but won't try to open an outbound connection.

"so"

The transport will try to open a connection simultaneously with its peer.

tcpType is null for UDP candidates.

Examples

In this example, the candidate's protocol and tcpType are used to adjust the user interface for simultaneous-open TCP candidates.

js
if (candidate.protocol === "tcp" && candidate.tcpType === "so") {
  adjustForSimultaneousOpen(candidate);
}

Specifications

Specification
WebRTC: Real-Time Communication in Browsers
# dom-rtcicecandidate-tcptype

Browser compatibility

Report problems with this compatibility data on GitHub
desktopmobile
Chrome
Edge
Firefox
Opera
Safari
Chrome Android
Firefox for Android
Opera Android
Safari on iOS
Samsung Internet
WebView Android
WebView on iOS
tcpType

Legend

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Full support
Full support

See also