An SSH login would be nice but I don't think it's necessary.
Updates and configuration are also possible via the web interface (HTTPS).
The cameras send the videos to the server via SFTP.
The live view is a little more complex. But it works via RTSP and ffmpeg (on the server). With a little bit of tinkering you only need an HTML5 video tag to play the videos.

What doesn't work is zooming or rotating. The web interface must be examined for this. It generates an access token after login, so everything can be accessed via HTTP requests. But I was too lazy to program it until now.