Networking enumeration is a powerful tool for hackers and is used by attackers and defenders alike. There are many different network enumerators available, with different specialties. The previous exercise was based on NMap. NMap is versatile, capable of everything from simple port scanning to running scripts that attempt to determine whether specific vulnerabilities exist on a target. It’s also free and open-source.

Another common network enumeration tool is Nessus, a paid tool designed more for defensive use. Some exploitation frameworks, such as Metasploit, also include network enumeration tools.