rtsp-simple-server/docs/4-other/08-proxy.md

Proxy

The server allows to proxy incoming requests to other servers or cameras. This is useful to expose servers or cameras behind a NAT. Edit mediamtx.yml and replace everything inside section paths with the following content:

paths:
  "~^proxy_(.+)$":
    # If path name is a regular expression, $G1, $G2, etc will be replaced
    # with regular expression groups.
    source: rtsp://other-server:8554/$G1
    sourceOnDemand: yes

All requests addressed to rtsp://server:8854/proxy_a will be forwarded to rtsp://other-server:8854/a and so on.