Much like Ncrack, Nping was added into the Nmap suite only very recently—its first iteration was created in August 2009 (along with Ncrack), and was first included in the actual Nmap suite in March 2010.

Although you might not expect it from its name, Nping does much more than ICMP echo requests (what we typically call a ping)—primarily, it can also execute ARP probes and TCP or UDP requests to given ports, in order to find out if those hosts are online based on the response. For example, if we want to debug certain network connections, we can easily use Nping to determine what's happening on the wire. The following screenshot shows a basic Nping command:

In the preceding screenshot, we ran Nping with two checks per port (-c 2, where "c" stands for "count"), and scanned ports on dshaw.net—80. In this case, 80 is an open port (it is running my web server), and we can clearly see the responses we're expecting. As we remember from earlier chapters, we can now see exactly...