RTCConfiguration - Web APIs 编辑

The RTCConfiguration dictionary is used to provide configuration options for an RTCPeerConnection. It may be passed into the constructor when instantiating a connection, or used with the RTCPeerConnection.getConfiguration() and RTCPeerConnection.setConfiguration() methods, which allow inspecting and changing the configuration while a connection is established.

The options include ICE server and transport settings and identity information.

Properties

bundlePolicy Optional

Specifies how to handle negotiation of candidates when the remote peer is not compatible with the SDP BUNDLE standard. This must be one of the values from the enum RTCBundlePolicy. If this value isn't included in the dictionary, "balanced" is assumed.

certificates Optional

An Array of objects of type RTCCertificate which are used by the connection for authentication. If this property isn't specified, a set of certificates is generated automatically for each RTCPeerConnection instance. Although only one certificate is used by a given connection, providing certificates for multiple algorithms may improve the odds of successfully connecting in some circumstances. See Using certificates for further information. This configuration option cannot be changed after it is first specified; once the certificates have been set, this property is ignored in future calls to RTCPeerConnection.setConfiguration().

iceCandidatePoolSize Optional

An unsigned 16-bit integer value which specifies the size of the prefetched ICE candidate pool. The default value is 0 (meaning no candidate prefetching will occur). You may find in some cases that connections can be established more quickly by allowing the ICE agent to start fetching ICE candidates before you start trying to connect, so that they're already available for inspection when RTCPeerConnection.setLocalDescription() is called. Changing the size of the ICE candidate pool may trigger the beginning of ICE gathering.

iceServers Optional

An array of RTCIceServer objects, each describing one server which may be used by the ICE agent; these are typically STUN and/or TURN servers. If this isn't specified, the connection attempt will be made with no STUN or TURN server available, which limits the connection to local peers.

iceTransportPolicy Optional

The current ICE transport policy; this must be one of the values from the RTCIceTransportPolicy enumeration. If the policy isn't specified, all is assumed by default, allowing all candidates to be considered. A value of relay limits the candidates to those relayed through another server, such as a STUN or TURN server.

peerIdentity Optional

A DOMString which specifies the target peer identity for the RTCPeerConnection. If this value is set (it defaults to null), the RTCPeerConnection will not connect to a remote peer unless it can successfully authenticate with the given name.

rtcpMuxPolicy Optional

The RTCP mux policy to use when gathering ICE candidates, in order to support non-multiplexed RTCP. The value must be one of those from the RTCRtcpMuxPolicy enum. The default is "require".

Constants

RTCBundlePolicy enum

The RTCBundlePolicy enum defines string constants which are used to request a specific policy for gathering ICE candidates if the remote peer isn't "BUNDLE-aware" (compatible with the SDP BUNDLE standard for bundling multiple media streams on a single transport link). All browser implementations are BUNDLE-aware.

If the remote endpoint is BUNDLE-aware, all media tracks and data channels are bundled onto a single transport at the completion of negotiation, regardless of policy used, and any superfluous transports that were created initially are closed at that point.

Note: In technical terms, a BUNDLE lets all media flow between two peers flow across a single 5-tuple; that is, from a single IP and port on one peer to a single IP and port on the other peer, using the same transport protocol.

RTCIceTransportPolicy enum

The RTCIceTransportPolicy enum defines string constants which can be used to limit the transport policies of the ICE candidates to be considered during the connection process.

RTCRtcpMuxPolicy enum

The RTCRtcpMuxPolicy enum defines string constants which specify what ICE candidates are gathered to support non-multiplexed RTCP. <<<add a link to info about multiplexed RTCP.

Example

The configuration below establishes two ICE servers. The first one, stun:stun.services.mozilla.com, requires authentication, so the username and password are provided. The second server has two URLs: stun:stun.example.com and stun:stun-1.example.com.

var configuration = { iceServers: [{
                          urls: "stun:stun.services.mozilla.com",
                          username: "louis@mozilla.com",
                          credential: "webrtcdemo"
                      }, {
                          urls: ["stun:stun.example.com", "stun:stun-1.example.com"]
                      }]
};

var pc = new RTCPeerConnection(configuration);

Specifications

Browser compatibility

BCD tables only load in the browser