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Tips and Tricks: Nmap is still relevant

Anecdotally, it would take about a week for a single machine to ping sweep the Internet. That would be approximately 4 billion IP addresses, essentially the whole Internet. In theory, this includes every single military address, every single ISP, every home user, and every mobile device. Such a port sweep does not include all options, UDP, and Nmap Scripts, as that would take too long. But what if I want to run the same scan to my home IPv6 range? It will have a /64 allocated to it, or about 18 quintillion addresses. Let’s compare a sweep of the entire Internet with my home IPv6 range:

  • The Internet: 2^32 = 4,294,967,296 [1]
  • The home range from my ISP: 2^64 = 18,446,744,073,709,551,616 [2]

A stark difference! So, how will I scan this? Is that just one network? I am Moses Hernandez, and this is one of my tips and tricks in this series. This post is about the venerable Nmap. Read More »

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