How RTMP is used today
The platform gives you an ingest address and a stream key. You enter them in your encoder, which opens a persistent connection and pushes the stream. The platform receives it, transcodes it into several qualities and delivers it to viewers over HLS or DASH.
RTMP is no longer used to reach viewers. Browsers dropped Flash, and segment-based protocols scale far better through CDNs.
Variants
- RTMP: the basic protocol, unencrypted
- RTMPS: RTMP over TLS, encrypted in transit; the version to use
- Enhanced RTMP: a newer extension adding support for codecs such as H.265 and AV1
Strengths and limits
- Strength: supported by virtually every encoder and platform
- Strength: simple to set up, with a delay of only a few seconds
- Limit: built on TCP, so it stalls and falls behind on a lossy connection
- Limit: classic RTMP carries only H.264 video and AAC audio
- Limit: weak support for multiple audio tracks and modern metadata
RTMP vs SRT
SRT is a newer contribution protocol that runs over UDP with its own error recovery and built-in encryption. It holds up much better over unreliable networks, such as a venue's shared internet or a cellular link. RTMP remains the default because it is everywhere; SRT is the better choice when the network is the risk.
Last reviewed