RTCIceCandidatePairStats
The RTCIceCandidatePairStats
dictionary of the WebRTC API is used to report statistics that provide insight into the quality and performance of an RTCPeerConnection
while connected and configured as described by the specified pair of ICE candidates.
The statistics can be obtained by iterating the RTCStatsReport
returned by RTCPeerConnection.getStats()
until you find an entry with the type
of "candidate-pair"
.
Instance properties
availableIncomingBitrate
Optional-
Provides a value representing the available inbound capacity of the network by reporting the total number of bits per second available for all of the candidate pair's incoming RTP streams. This does not take into account the size of the IP overhead, nor any other transport layers such as TCP or UDP.
availableOutgoingBitrate
Optional-
Provides an informative value representing the available outbound capacity of the network by reporting the total number of bits per second available for all of the candidate pair's outgoing RTP streams. This does not take into account the size of the IP overhead, nor any other transport layers such as TCP or UDP.
bytesReceived
Optional-
The total number of payload bytes received (that is, the total number of bytes received minus any headers, padding, or other administrative overhead) on this candidate pair so far.
bytesSent
Optional-
The total number of payload bytes sent (that is, the total number of bytes sent minus any headers, padding, or other administrative overhead) so far on this candidate pair.
currentRoundTripTime
Optional-
A floating-point value indicating the total time, in seconds, that elapsed between the most recently-sent STUN request and the response being received. This may be based upon requests that were involved in confirming permission to open the connection.
lastPacketReceivedTimestamp
Optional-
A
DOMHighResTimeStamp
value indicating the time at which the last packet was received by the local peer from the remote peer for this candidate pair. Timestamps are not recorded for STUN packets. lastPacketSentTimestamp
Optional-
A
DOMHighResTimeStamp
value indicating the time at which the last packet was sent from the local peer to the remote peer for this candidate pair. Timestamps are not recorded for STUN packets. localCandidateId
Optional-
The unique ID string corresponding to the
RTCIceCandidate
from the data included in theRTCIceCandidateStats
object providing statistics for the candidate pair's local candidate. nominated
Optional-
A Boolean value which, if
true
, indicates that the candidate pair described by this object is one which has been proposed for use, and will be (or was) used if its priority is the highest among the nominated candidate pairs. See RFC 5245, section 7.1.3.2.4 for details. remoteCandidateId
Optional-
The unique ID string corresponding to the remote candidate from which data was taken to construct the
RTCIceCandidateStats
object describing the remote end of the connection. requestsReceived
Optional-
The total number of connectivity check requests that have been received, including retransmissions. This value includes both connectivity checks and STUN consent checks.
requestsSent
Optional-
The total number of connectivity check requests that have been sent, not including retransmissions.
responsesReceived
Optional-
The total number of connectivity check responses that have been received.
responsesSent
Optional-
The total number of connectivity check responses that have been sent. This includes both connectivity check requests and STUN consent requests.
state
Optional-
A string which indicates the state of the connection between the two candidates.
totalRoundTripTime
Optional-
A floating-point value indicating the total time, in seconds, that has elapsed between sending STUN requests and receiving responses to them, for all such requests made to date on this candidate pair. This includes both connectivity check and consent check requests. You can compute the average round trip time (RTT) by dividing this value by
responsesReceived
. transportId
Optional-
A string that uniquely identifies the
RTCIceTransport
that was inspected to obtain the transport-related statistics (as found inRTCTransportStats
) used in generating this object.
Common instance properties
The following properties are common to all WebRTC statistics objects.
id
-
A string that uniquely identifies the object that is being monitored to produce this set of statistics.
timestamp
-
A
DOMHighResTimeStamp
object indicating the time at which the sample was taken for this statistics object. type
-
A string with the value
"candidate-pair"
, indicating the type of statistics that the object contains.
Deprecated properties
The following properties have been removed from the specification and should no longer be used. You should update any existing code to avoid using them as soon as is practical. Check the compatibility table for details on which browsers support them and in which versions.
priority
Deprecated Optional-
An integer value indicating the candidate pair's priority.
readable
Deprecated Optional Non-standard-
A Boolean value indicating whether or not data can be sent over the connection described by the candidate pair.
writable
Deprecated Optional Non-standard-
A Boolean value indicating whether or not data can be received on the connection described by the candidate pair.
Non-standard properties
selected
Non-standard Optional-
A Firefox-specific Boolean value which is
true
if the candidate pair described by this object is the one currently in use. The spec-compliant way to determine the selected candidate pair is to look for a stats object of typetransport
, which is anRTCTransportStats
object. That object'sselectedCandidatePairId
property indicates whether or not the specified transport is the one being used.
Usage notes
The currently-active ICE candidate pair—if any—can be obtained by calling the RTCIceTransport
method getSelectedCandidatePair()
, which returns an RTCIceCandidatePair
object, or null
if there isn't a pair selected.
The active candidate pair describes the current configuration of the two ends of the RTCPeerConnection
.
Any candidate pair that isn't the active pair of candidates for a transport gets deleted if the RTCIceTransport
performs an ICE restart, at which point the state
of the ICE transport returns to new
and negotiation starts once again.
For more information, see ICE restart.
Example
This example computes the average time elapsed between connectivity checks.
js
if (rtcStats && rtcStats.type === "candidate-pair") {
let elapsed =
(rtcStats.lastRequestTimestamp - rtcStats.firstRequestTimestamp) /
rtcStats.requestsSent;
console.log(`Average time between ICE connectivity checks: ${elapsed} ms.`);
}
The code begins by looking at rtcStats
to see if its type
is candidate-pair
.
If it is, then we know that rtcStats
is in fact an RTCIceCandidatePairStats
object.
We can then compute the average time elapsed between STUN connectivity checks and log that information.
Specifications
Specification |
---|
Identifiers for WebRTC's Statistics API # dom-rtcstatstype-candidate-pair |
Browser compatibility
BCD tables only load in the browser