RTPAUDIOQOS Demystified
How to read such line:
ssrc=254186206;themssrc=2024901615;lp=0;rxjitter=0.020917;rxcount=150;txjitter=0.000000;txcount=83;rlp=0;rtt=14818.715000
- Our Receiver
- ssrc - our ssrc
- rxcount - no. received packets/Received packets
- lp - lost packets/Lost packets
- rxjitter - our calculated jitter(rx)/Jitter
- Our Sender
- themssrc - their ssrc
- txcount - transmitted packets/Sent packet
- rlp - remote lost packets/Lost packets
- txjitter - reported jitter of the other end/Jitter
- rtt - round trip time/RTT
Synchronization source (SSRC)
The source of a stream of RTP packets, identified by a 32-bit numeric SSRC identifier carried in the RTP header so as not to be dependent upon the network address. All packets from a synchronization source form part of the same timing and sequence number space, so a receiver groups packets by synchronization source for playback. Examples of synchronization sources include the sender of a stream of packets derived from a signal source such as a microphone or a camera, or an RTP mixer (see below). A synchronization source may change its data format, e.g., audio encoding, over time. The SSRC identifier is a randomly chosen value meant to be globally unique within a particular RTP session (see Section 8). A participant need not use the same SSRC identifier for all the RTP sessions in a multimedia session; the binding of the SSRC identifiers is provided through RTCP (see Section 6.5.1). If a participant generates multiple streams in one RTP session, for example from separate video cameras, each MUST be identified as a different SSRC.
