These states are not intrinsic properties of the port itself, but describe how Nmap sees them. It divides ports into six states: open, closed, filtered, unfiltered, open|filtered, or closed|filtered. While many port scanners have traditionally lumped all ports into the open or closed states, Nmap is much more granular. The simple command nmap scans 1,000 TCP ports on the host. While Nmap has grown in functionality over the years, it began as an efficient port scanner, and that remains its core function. Nmap’s power can be summarized as follows In addition to the classic command-line Nmap executable, the Nmap suite includes an advanced GUI and results viewer (Zenmap), a flexible data transfer, redirection, and debugging tool (Ncat), a utility for comparing scan results (Ndiff), and a packet generation and response analysis tool (Nping).
#PROBE FIREWALL ZENMAP MAC OS#
Nmap runs on all major computer operating systems, and official binary packages are available for Linux, Windows, and Mac OS X.
It was designed to rapidly scan large networks, but works fine against single hosts. Nmap uses raw IP packets in novel ways to determine what hosts are available on the network, what services (application name and version) those hosts are offering, what operating systems (and OS versions) they are running, what type of packet filters/firewalls are in use, and dozens of other characteristics. Many systems and network administrators also find it useful for tasks such as network inventory, managing service upgrade schedules, and monitoring host or service uptime. Nmap or Network Mapper is a free and open source utility for network discovery and security auditing.