It depend on what you want to do with it. As I see the the camera supports multiple streams and protocols.
If you want the video stream, you should probably attach to it via RTSP, using the url described here:
http://www.marmitek.com/en/support/live-demo-ip-camera.php[
^]. You can find .net libraries for that, like this one:
http://www.streamcoders.com/products/msnet.html[
^], or you can simply embed a player component that is able to show it for you, if that's the only need.
But everything else is up to what you want to do.