Hi,
It depends on the camera if it streams rtmp protocol or not.
However you should first verify the stream protocols the camera is streaming before buying. The thing is that for sure camera will have at least one protocol to be streamed on. And in most cases you can live broadcast the camera on your site.
You can do that without any additional plugin. Just you have to know the ip of the camera it is streaming on. The port of the camera it is streaming on. You can check such live broad casting cameras here -
http://www.viralcameras.com/0/posts/...ent/page2.html 
Click on the video of the camera and you will be able to manage the camera - to zoom it to tilt. In admin mode.