I do this all the time with our installs now even if the recorder is in the same rack as the network. This allows for a lot more flexibility installation wise and setup wise on the cameras themselves. This makes it a lot easier for the Crestron jobs to be able to bring the ONVIF stream onto the touch panels for each camera (I know there are other ways to do this). All cameras are set to static/DHCP reserved addresses so they can be added to the recorder. Additionally you could eliminate the recorder and just install SD cards into all the cameras.