In this tip we're going to explore a couple of ways to find open IP (Internet Protocol) addresses on your network. You might need this information if you were going to temporarily set a static IP address for a host. Even after you've found an open IP though, you still need to take care to avoid IP conflicts if your network uses DHCP (Dynamic Host Configuration Protocol). Please also be aware that one of these techniques uses the nmap network scanning program, which may be against policy in some environments. Even if it's not against corporate policy, the nmap man page states that "there are administrators who become upset and may complain when their system is scanned. Thus, it is often advisable to request permission before doing even a light scan of a network."