You can use the hostname of the License Server Administrator or the IP address. On the system that is running License Server Administrator you can click on the Start button if applicable and then right-click on Computer and select Properties. You should find the name under Computer name.
You can also open up a command prompt on the system running the License Server Administrator and type the command hostname and enter and this should display the hostname.
I hope this helps, if not let me know and we can discuss further.