Sep 1, 2017 · Flexible: Supports dozens of advanced techniques for mapping out networks filled with IP filters, firewalls, routers, and other obstacles. This includes many port scanning mechanisms (both …

Ports are simply a software abstraction, used to distinguish between communication channels. Similar to the way IP addresses are used to identify machines on networks, ports identify specific applications …

Nmap sends an ICMP type 8 (echo request) packet to the target IP addresses, expecting a type 0 (echo reply) in return from available hosts. Unfortunately for network explorers, many hosts and firewalls …

You can join the 128,953 current subscribers (as of September 2017) by submitting your email address here: (or subscribe with custom options from the Nmap-hackers list info page) You can also get …

For example, disable “hostname” to show only an IP address for each host, or disable “address” to use no labels at all. The “latency” option enables and disables the display of the round-trip times to each …

It summarizes details about a single host or a complete scan in a convenient display. Zenmap can even draw a topology map of discovered networks. The results of several scans may be combined …

By default, Nmap resolves names to IP addresses (and IP addresses to names) by sending queries directly to the name servers configured on your host and then listening for responses.

Launches host enumeration and a TCP scan at the first half of each of the 255 possible eight-bit subnets in the 198.116.0.0/16 address space. This tests whether the systems run SSH, DNS, POP3, or IMAP …

They can be helpful in showing that a host is up on an IP address (host discovery, or ping scanning), and as part of OS detection. Because closed ports are reachable, it may be worth scanning later in …

While some tools have simple interfaces that only allow a list of hosts or maybe let you specify the start and end IP addresses for a range, Nmap is much more powerful and flexible.