The WebRTC interface RTCRtpTransceiver
describes a permanent pairing of an RTCRtpSender
and an RTCRtpReceiver
, along with some shared state.
Each SDP media section describes one bidirectional SRTP ("Secure Real Time Protocol") stream (excepting the media section for RTCDataChannel
, if present). This pairing of send and receive SRTP streams is significant for some applications, so RTCRtpTransceiver
is used to represent this pairing, along with other important state from the media section. Each non-disabled SRTP media section is always represented by exactly one transceiver.
A transceiver is uniquely identified using its mid
property, which is the same as the media ID (mid
) of its corresponding m-line. An RTCRtpTransceiver
is associated with an m-line if its mid
is non-null; otherwise it's considered disassociated.