RFC 3550 / START HERE
RTP / RTCP, before the details
RTP: Real-time Transport Protocol
RTP carries time-sensitive media such as audio and video, with sequence numbers and timestamps that help a receiver play it. Its companion RTCP carries control and quality information.
The idea in one picture
Audio or video is packetized
RTP carries sequence and timing
A receiver prepares playback
A simplified picture of the idea; the chapters explain the actual mechanisms.
Why it exists
A receiver needs to recognize timing, ordering, and losses in media traffic. These fields support playback but do not guarantee timely delivery.
A familiar example
A voice app sends small audio packets that the receiving app orders and plays according to their media timing.
Helpful background
You can start here without reading another RFC. If these ideas are unfamiliar, these short introductions may help.
What you’ll learn next
Begin with chapter one, or choose a topic.
- A media packet has two clocksThe sequence number orders packets; the timestamp locates media in its sampling timeline.→
- A gap is not reliable deliverySequence numbers help detect missing packets but RTP does not guarantee their retransmission or arrival.→
- Arrival jitter is measurableRTCP interarrival jitter estimates changes in the relative transit time of media packets.→
- Reports describe receptionRTCP reports communicate reception statistics alongside RTP media.→
- Synchronize related mediaSender reports map each RTP clock to a shared wall-clock reference.→
This introduction explains RFC 3550 (2003). Read the original RFC ↗