RTSP vs WebRTC vs HLS, plus SRT, RTMP and ONVIF, compared in plain English for security teams: speed, reach, reliability and which job each protocol does best.
Every security video system relies on a few protocols, the agreed rules for moving video across a network. Each was designed for a different job, and choosing the right mix is one of the most important decisions in any video platform.
Six matter most for surveillance in 2026: RTSP, WebRTC, HLS (including LL-HLS), SRT, RTMP and ONVIF. Here is what each does, in plain terms.
WebRTC delivers the fastest live video of any protocol a browser can play, in well under a second. It finds its way through home and office networks automatically and works in Chrome, Firefox, Safari and Edge with no plugins.
Running it across many cameras and viewers takes careful engineering. Visylix handles all of that for you, pulling each camera once and relaying it to every viewer, with sub second live view down to under 200 ms.
HLS is excellent for recorded playback and very large audiences, but runs several seconds behind live. Low Latency HLS narrows the gap to a few seconds, which suits overview screens but not live response. SRT (Secure Reliable Transport) moves video reliably over unpredictable links, which makes it ideal for remote cameras on cellular or satellite connections.
RTMP began life with Flash and no browser plays it today. It remains useful for pushing video into a platform from encoders and some cameras. ONVIF is different again: it is the standard that lets a platform discover cameras, control PTZ and receive camera events, whatever the brand.
No single protocol covers every job. The right answer is one platform that takes video in over RTSP, RTMP or SRT and delivers it over WebRTC for live monitoring, HLS for playback and SRT for remote links.
Visylix does exactly that with its own native streaming engine. It speaks 13+ protocols at once: RTSP, RTMP, HLS, LL-HLS, MPEG-DASH, HTTP-FLV, HTTP-TS, WebRTC with WHEP and WHIP, SRT, NDI and OMT, plus RIST and GB28181 ingest and ONVIF camera control. Every camera and every viewer uses whichever protocol suits their network, and live tiles fall back from WebRTC to HLS or HTTP-TS automatically where needed.
On top of that foundation, Visylix watches every feed with 22 AI analytics built in house and acts on what it sees, entirely on your own hardware.
WebRTC. It delivers live video in well under a second in any modern browser, with no plugins, and Visylix brings it down to under 200 ms. Use HLS for recorded playback and large audiences, RTSP to pull video from cameras inside your network, and SRT for remote cameras on unreliable links.
Visylix supports 13+ protocols in its own native streaming engine: RTSP, RTMP, HLS and LL-HLS, MPEG-DASH, HTTP-FLV, HTTP-TS, WebRTC with WHEP and WHIP, SRT, NDI and OMT, plus RIST and GB28181 ingest and ONVIF camera control. Each camera and each viewer can use the protocol that best fits their network.
RTSP works well between cameras and servers on a local network, but browsers cannot play it and it struggles to cross firewalls for remote viewing. You need a platform that takes RTSP in and delivers WebRTC or HLS out, which is exactly what Visylix does.
Yes, as a way to send video in. No browser plays RTMP since Flash was retired, but many encoders and some cameras still push RTMP. Most modern systems take RTMP in and send WebRTC or HLS out, and Visylix supports that pattern.