OK, so you don’t necessarily call rtsp on Ubuntu QuickTime Streaming Server. Instead, you call it Darwin Streaming Server (DSS). But the end result is basically what you have exposed in Mac OS X Server, but running on Linux. You don’t have the same functionality in Server Admin, but it does work. And the key to what it does is use the rtsp protocol to stream supported files from the server to clients. It is a little tougher than just clicking on the start button, but too much tougher provided you follow these directions (thanks to the good folks of the DSS list that I’ve been a member of for…