Comparing RTMP with RTSP, both protocol offers content security by transferring chunks of media data instantly consumed by media player without any local caching. The characteristics are:
RTMP:
It’s a proprietary protocol originally by Macromedia (now Adobe) that usually encapsulates the data in http/https frames. Usually used by the flash player;
It support all formats;
Use default port 1935;
RTMP used different protocol and port from HTTP, which make it vulnerable to blocked by cooperate firewall;
RTMP data is stream to player, it required a bigger connection bandwidth.
RTSP:
RTSP is a network control protocol used to create streaming sessions between a server and client.
User needs to initiate a session;
It requires H264 encoder video;
It requires H265 encoder video;
It default port is 554;
Streaming with RTSP fails if a firewall separates the client and server, and the firewall blocks the ports and protocols that RTSP uses. This problem is especially common with home Internet gateways.